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Study Identifies Dog Breeds, Physical Traits That Pose Highest Risk Of Biting Children
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May 22, 2019
COLUMBUS, Ohio – New research at The Ohio State University College of Medicine and The Ohio State University Wexner Medical Center identifies dog breeds and physical traits that pose the highest risk of biting with severe injury. Doctors want parents of young children to use this information when deciding which dog to own.
The study, published in the International Journal of Pediatric Otorhinolaryngology , explores the risks of dog bite injuries to the face in children and bite severity by breed, size and head structure. Researchers found pit bulls and mixed breed dogs have the highest risk of biting and cause the most damage per bite. The same goes for dogs with wide and short heads weighing between 66 and 100 pounds.
“The purpose of this study was to evaluate dog bites in children, and we specifically looked at how breed relates to bite frequency and bite severity,” said Dr. Garth Essig , lead author and otolaryngologist at Ohio State’s Wexner Medical Center. “Because mixed breed dogs account for a significant portion of dog bites, and we often didn’t know what type of dog was involved in these incidents, we looked at additional factors that may help predict bite tendency when breed is unknown like weight and head shape.”
To assess bite severity, researchers reviewed 15 years of dog-related facial trauma cases from Nationwide Children’s Hospital and the University of Virginia Health System. They looked at wound size, tissue tearing, bone fractures and other injuries severe enough to warrant consultation by a facial trauma and reconstructive surgeon and created a damage severity scale.
Researchers also performed an extensive literature search from 1970 to current for dog bite papers that reported breed to determine relative risk of biting from a certain breed. This was combined with hospital data to determine relative risk of biting and average tissue damage of bites.
“There’s an estimated 83 million owned dogs in the United States and that number continues to climb,” said Dr. Essig. “We wanted to provide families with data to help them determine the risk to their children and inform them on which types of dogs do well in households with kids.”
According to the Centers for Disease Control and Prevention, 4.7 million people in the United State are bitten by dogs annually, and 20 percent of these victims require medical care for their injuries. Those who require treatment after dog bites are predominately children ages 5 to 9 years.
“Young children are especially vulnerable to dog bites because they may not notice subtle signs that a dog may bite,” said Dr. Charles Elmaraghy , study co-author, associate professor of otolaryngology at Ohio State’s College of Medicine and chief of otolaryngology at Nationwide Children’s Hospital. “We see everything from simple lacerations to injuries in which there’s significant tissue loss that needs grafting or other reconstructive surgery.”
Dr. K. Craig Kent , dean of The Ohio State University College of Medicine said, “This research highlights a significant public health issue and provides a new decision-making framework for families considering dog ownership.”
The circumstances that cause a dog to bite vary and may be influenced by breed behavior tendencies and the behavior of the victim, parents and dog owner.
“Children imitate their parents,” said Meghan Herron, associate professor of veterinary clinical services at Ohio State’s College of Veterinary Medicine. “Be a model for your child and avoid any confrontational or risky interactions that might trigger a fear or fear-aggression response if the child were to mimic it. This includes harsh reprimands, smacking, pushing off of furniture and forcibly taking away an item.”
Herron offers the following tips for dog owners:
- Most bites to children occur from a family dog when the dog is resting and the child approaches. Try to provide and encourage resting places away from where children run and play.
- Many bites to children occur even when an adult is in the room. If you can’t devote your attention to the interactions between the dog and child, it may be best to have a physical barrier between them, such as a baby gate or crate for the dog. This is especially important for toddlers whose behaviors may be more erratic, unpredictable or frightening to a dog.
- Teach children to let resting dogs lie and to stay out of dog crates, beds and other resting places that are designated for the dog. If the dog’s favorite spot is on the couch, put a towel or blanket down to clearly delineate the dog space versus child space.
- Children should not approach, touch or otherwise interact with dogs while they are eating. Provide quiet areas for dogs to eat away from areas where children run and play. Rawhides and other flavored chews should only be given when dogs are separated from child play areas.
- Teach children to find an adult if a dog takes one of their toys or snacks. Children should never attempt to retrieve these items themselves.
Other researchers involved in this study were Dr. Cameron Sheehan, Dr. Shefali Rikhi and Dr. J. Jared Christophel.
Media Contact: Serena Smith, Wexner Medical Center Public Affairs and Media Relations, 614-293-3737, [email protected]
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Here’s Why It’s Important To Research Dog Breeds
There’s no doubt that dogs are members of the family who bring an insurmountable amount of joy. That said, there are many pet parents out there who own a breed of dog that may become challenging once they leave puppyhood and enter their teenage months and beyond.
Before purchasing or adopting a particular breed, it’s important to research the reasoning behind what these fascinating dogs were initially bred to do. For example, was the breeding goal aimed for sport, protection, work or another reason?
It’s essential to arm yourself with knowledge about a particular breed before committing to it. Yes, while dogs have become more domesticated over the years, as a dog matures, their genetics at some point surfaces.
Here are some highlights of some popular breeds whose instincts may likely kick in over time.
The German Shepherd Dog
Originally bred to guard flocks in the mid-1850s, German Shepherds have evolved over the years also to perform tasks including working K9s and participation in the sport dog world.
This loyal breed has a keen sense of smell, is highly athletic, and protective by nature as they mature.
Those who own this fabulous breed sometimes note how when their dogs reach their teenage years and beyond, a protective and reactive tendency may sometimes develop.
For those who have the interest or inclination, pet parents may seek activities with their dog such as nose-work, Schutzhund, herding and more.
Cattle Dogs and Australian Shepherds
Best described as brave, loyal, and energetic, these breeds are the top-tier choice when it comes to herding. These dogs are a cowboy’s first pick. This amazing breed that was bred to herd also has a piercing stare when they are in a working mode to move livestock or flocks. After all, that was what they were bred to do back in the day.
These dogs are high energy and require exercise.
As this intellectual breed matures, many pet parents note how their dogs tend to nip at their heels (like they would toward cattle). Be sure to give them the academic and physical stimulation they require, such as finding a place which does herding.
The Terrier Breeds
Be it a Jack Russell Terrier, Fox Terrier or any Terrier, these dogs were meant to hunt. And yes, that means digging, too. Originally, this breed was intended to hunt rats, foxes, moles and more. For those that own this breed, they often laugh when they hear the common moniker, “Terror.”
Common complaints from pet parents include how their dogs having selective hearing during a recall, dig holes in the yard, among other breed characteristics. When a terrier catches wind of a “scent,” they’re off, and they mean business.
Many who own this breed find a lure course an excellent choice for their terrier to unleash their natural talents.
What’s A Pet Parent To Do?
As mentioned earlier, it’s essential to research what a dog was bred for in the first place before purchasing or adopting. At some point, their instincts will emerge. If a family already owns a breed like this, be sure to establish solid obedience skills under distraction while allowing your dog to take part in one of the activities mentioned.
If you have any questions or concerns about your furry family member and their breed, contact us today !
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20 Most Fascinating Scientific Studies on Dogs
W e all know that dogs are amazing , but do you know just how amazing they really are? Scientists have been carrying out many different studies on dogs over the years, and they have discovered numerous fascinating and truly unbelievable things about them. The best scientific studies on dogs have proven many things about the species and their connection to humans.
Science is proving that dogs are very beneficial to our physical and mental well-being. I mean, we don't call them “man's best friend” for nothing, right? Studies have been done on the effects of dogs on humans, including children, and how they benefit us both mentally and physically .
Most of us probably don't spend a whole lot of time reading up on different canine studies done over the years. Today I'd like to share a few of the best scientific studies on dogs with you, because I think you'll be surprised at some of the findings.
Best Scientific Studies on Dogs
1. pets keep us fit.
Dog owners are much fitter because they own a dog, which makes sense if you think about it. You have to walk your dog daily to keep him happy and fit, and so you too become fitter.
A study that included 2,000 adults discovered that those who regularly walked their dog were less likely to be obese, compared with those who didn’t have a dog to walk. Older walkers can benefit too, as in another study it was found that walkers aged between 71 and 82 could walk longer and indeed faster than non dog walkers.
Read more about the study: http://www.ncbi.nlm.nih.gov/pubmed/16459211
2. Dogs can prevent allergies and help boost your immune system
Studies have discovered that living with a dog, especially when you’re young, will prevent you from having allergies when you’re older. By having a dog, your immune system is boosted and the pet will also lower your risk of suffering from asthma and also eczema. Your immune system doesn’t need long with a dog to be boosted either – just a short amount of time is enough.
One of the best scientific studies on dogs showed that just patting a dog for 18 minutes increased saliva and raised immunoglobulin A (IgA) levels in the saliva. These raised levels mean that you have a very strong immune system.
3. Dogs reduce stress
Studies have found that owning a dog can greatly reduce your stress levels. When you have contact with a dog your stress response is lowered, and this lowers stress hormones like cortisol and your heart rate is lowered too.
Dogs can also help to lower anxiety and fear and will help to increase feelings of calmness. A study found that elderly people who walked their dogs every day had an enhanced heart rate, which is a sign of low stress levels.
Read more about the study: https://www.mja.com.au/journal/2006/184/2/effect-dog-walking-autonomic-nervous-activity-senior-citizens
4. Dogs make you more social
Studies have found that dogs make us more social, as when we walk our dogs we are out and about meeting and greeting different people. They act as icebreakers and people are far more likely to talk to you if you have a dog. One study discovered that people in wheelchairs who are with dogs received more smiles from others.
Read more about the study: http://www.health.harvard.edu/blog/pets-can-help-their-humans-create-friendships-find-social-support-201505067981
5. Dogs prevent heart attacks and strokes
Some of the best scientific studies on dogs relating to heart health have discovered that dogs can dramatically reduce your chances of having a heart attack or stroke. Dog owners have a decrease in blood pressure compared to non dog owners. Dog owners also have a reduction in cholesterol levels and also triglyceride levels.
If you have high levels of these then your chances of having a heart attack or stroke is high. Studies also found that if you have already had a heart attack or stroke you will recover faster if you have a dog.
Read more about the study: http://circ.ahajournals.org/content/early/2013/05/09/CIR.0b013e31829201e1.full.pdf
6. Dogs keep depression away
Dogs make us laugh and they make us smile, when we are with our dogs we are happier. Studies have discovered that dogs really do keep depression away.
Our dogs love us unconditionally and they need us in order to stay healthy and strong. Studies show that when we’re around dogs we feel more positive about things.
Read more about the study: http://habri.org/depression
7. Dogs keep children healthy
When children grow up with a family dog around them, they are much stronger and have stronger immune systems which will reduce the chance of them having allergies. A study carried out in 2010 showed that if you are around a dog during the first year of life you are far less likely to develop chronic skin conditions.
Read more about the study: https://www.sciencedaily.com/releases/2010/09/100930093229.htm
8. Dogs help children develop
When a child grows up with a dog, there are many emotional benefits as well, and the best scientific studies on dogs have proven that. The child will have someone to talk to and spend time with.
Children can express themselves better when they have a dog around them. Children also learn responsibility when they have a dog. Studies have discovered that children with autism and AHDH also benefit greatly from dog ownership.
Read more about the study: http://www.ncbi.nlm.nih.gov/pubmed/25308197
9. Dogs help older people
Many studies have shown that an elderly person is much happier when they have a dog to look after. The dog is a great source of comfort to them and offers companionship. A dog will help to keep an elderly person connected and will greatly boost their vitality. Dogs will help to reduce the feelings of loneliness that elderly people can have.
Read more about the study: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3351901/
10. Dogs help Alzheimer’s patients
Studies have revealed that dogs really can help those suffering from Alzheimer’s disease. They show that dogs reduce behavioral issues amongst dementia patients by greatly boosting their moods. These studies also found that a patient’s nutritional intake is increased when around a dog.
Read more about the study: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4248608/
11. Dogs help against PTSD
Several studies have discovered that those suffering from PTSD are benefited greatly by the love of a dog. A dog boosts oxytocin levels in the body and can be a great help against the flashbacks that come with PTSD.
People suffering from PTSD can have angry outbursts and emotional numbness, but when around a dog this is greatly reduced. There are now many programs that team up those suffering with PTSD with dogs.
Read more about the study: http://www.mnn.com/family/pets/stories/nature-loving-pets-help-veteran-overcome-ptsd
12. Dogs can help you fight cancer
Dogs can help people suffering from cancer, and some of the best scientific studies on dogs are showing that canines ease the loneliness and depression that people with cancer can suffer from. Dogs encourage people to eat and keep up with their cancer treatment. Dogs really do try and help people recover from cancer. Canine companions benefit both adults and children that are fighting cancer.
Read more about the study: http://www.eurekalert.org/pub_releases/2015-01/tmsh-cts011315.php
13. Dogs reduce pain
Studies show that dogs can greatly reduce our pain and just 10-15 minutes with a dog is all it takes for pain to be reduced. Dogs also help improve your mood and can help with fatigue that comes with pain.
One study showed that people who had joint replacement surgery needed 28% less medication, thanks to being around a dog.
Read more about the study: https://www.sciencedaily.com/releases/2014/08/140807180314.htm
14. Dogs make you more attractive
Believe it or not, some of the best scientific studies on dogs show that people who own a canine are more attractive than non dog owners. They also show that women are more attracted to dog owners than non dog owners. So, if you’re out to impress, a dog will work wonders.
Read more about the study: http://www.slate.com/articles/health_and_science/science/2014/02/
15. Dogs help to strengthen bonds
Studies show that those who have a strong bond with their dog also have greater bonds with other people. One study involved 500 people aged between 18 and 26 and discovered that the ones that owned dogs had a closer bond with others.
Read more about the study: http://www.huffingtonpost.com/2014/02/03/pet-social-connectedness-young-adult_n_4703790.html
16. Dogs can detect cancer
A few of the best scientific studies on dogs have revealed that some dogs can literally sniff out cancer and could save your life. One dog named Marnie who is an eight year old black Labrador sniffed out cancer 91% of the time just by sniffing breath.
Marnie also showed that she can detect colorectal cancer 97% of the time by sniffing stools.
Read more about the study: http://abcnews.go.com/Health/CancerPreventionAndTreatment/dog-detects-colorectal-cancer-standard-screening-test/story?id=12805641
17. Dogs can detect food that you’re allergic to
Your dog knows exactly what you’re allergic to studies can reveal, and can smell just the hint of peanut butter. Peanut detecting dogs really can help to save the lives for those with peanut allergies.
Read more about the study: http://www.livescience.com/35463-seven-surprising-health-benefits-dog-ownership-110209.html
18. Dogs make us happy
A study in 2009 showed that our oxytocin levels were dramatically raised when we are in contact with a dog.
The study found that those who looked into a dog’s eye the longest had the highest readings of oxytoxin. No wonder we’re always happy when we’re with our best firends.
Read more about the study: http://www.ncbi.nlm.nih.gov/pubmed/19124024
19. Dogs bring out the caretaker in us
It has been found that just by looking at a dog’s face they can bring out the caretaker in us. Their large eyes, floppy ears and cute features make us feel that we have to take good care of them. We have the same reaction when we’re around infants.
Read more about the study: http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0058248
20. Dogs boost self esteem
When you have the responsibility of caring for your dog you feel so much better about yourself. You have someone to care for who loves you unconditionally and you have to do your very best for them.
When you have a dog to care for your whole outlook on life changes and you get to meet and greet new people as you’re walking your dog, resulting in higher self esteem.
Read more about the study: http://psycnet.apa.org/psycinfo/2011-13783-001/
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Dog study shows there's a lot more to behavior than just breed
When comparing dog breeds and mutts, distinctive physical traits are not highly correlated to inheritable behavior traits.
A genetic study of 2,155 purebred and mixed-breed dogs combined with 18,385 owner surveys has challenged existing notions about dog breed stereotypes and personality types. The study identified 11 locations along the canine genome that were strongly associated with behavior, none of which were specific for breed, suggesting that these personality traits predate modern canine breeding by humans.
“Using a really powerful model, these findings provide compelling support for the fact that complex traits, like behavior or personality, may have some genetic contribution, but that contribution is distributed across so many genes with really tiny effects," said Arizona State University School of Life Sciences Assistant Professor Noah Snyder-Mackler , who contributed to the study in a collaboration with investigators at the UMass Chan Medical School, including Elinor Karlsson, who led the study that was published in a recent issue of Science. "This means that while we can predict how biddable Biddability refers to a dog's ability to respond to human direction. a dog is on average, we will do a pretty terrible job predicting the biddability of a single dog based on their genotype, and definitely not their breed. It points to the fact that much of these complex traits are strongly impacted by the lived experiences of each individual.”
Canine behavioral disorders are often proposed as a natural model for human neuropsychiatric disorders. Compulsive disorders, for instance, are often observed to manifest similarly in both humans and dogs. Thanks to the power of current DNA sequencing technology and the close relationship between pet and owner, canine genome-wide association studies (GWAS ) have the potential to identify unique genetic areas in the dog genome that could lead to new insights into similar genes in humans. Karlsson and colleagues show that large-scale GWAS in dogs can yield genetic loci associated with behavioral traits.
“Although friendliness is the trait we commonly associate with golden retrievers, what we found is that the defining criteria of a golden retriever — what makes a golden retriever a golden retriever — are its physical characteristics, the shape of its ears, the color and quality of its fur, its size; not whether it is friendly,” said Karlsson, associate professor of molecular medicine at UMass Chan Medical School.
“While genetics plays a role in the personality of any individual dog, the specific dog breed is not a good predictor of those traits,” explained Karlsson, who is also the director of the Vertebrate Genomics Group at the Broad Institute of the Massachusetts Institute of Technology and Harvard University. “A dog’s personality and behavior are shaped by many genes as well as their life experiences. This makes them difficult traits to select for through breeding. For the most part, pure breeds are only subtly different from other dogs. A golden retriever is only marginally more likely to be more friendly than a mixed-breed or another purebred dog, such as a dachshund.”
A dog's tale
The story of how modern-day dog breeds emerged is a relatively short one in evolutionary terms, contrasted against the history of dog domestication from prehistoric wolves. Genetic research pegs the change from wolf to dog at about 10,000 to 15,000 years ago. Humans didn’t begin intentionally breeding dogs until roughly 2,000 years ago, when they were being selected for work roles such as hunting, guarding and herding. It wasn’t until the Victorian era in the 1800s that humans began selecting dogs consistently for the physical appearance and aesthetic traits that today we commonly associate with modern breeds.
Yet modern dog breeds are often credited with characteristics and temperaments (bold, affectionate, friendly, trainable) that correlate to their ancestral function (herding, guarding or hunting). Likewise, the breed ancestry of dogs is assumed to be predictive of temperament and behavior. DNA tests are even marketed as tools for dog owners to learn about a pet’s individual personality. However, there is a lack of genetic studies linking behavioral tendencies to ancestry or other genetic, heritable factors.
By pairing genome-wide association mapping technologies with pet owner surveys obtained through Darwin’s Ark, an open-source database of owner-reported canine traits and behaviors, Karlsson and first author Kathleen Morrill, a PhD student in the Morningside Graduate School of Biomedical Sciences at UMass Chan, explored the complicated relationship between modern canine breeds and behavioral characteristics.
Genome-wide association studies (GWAS) are an approach used in genetics research to try to associate specific areas of variation in the human genome that align with certain phenotypes. Taking whole genome sequences from hundreds of thousands of people with the same disease, for instance, researchers look for common genetic variations among these people to pinpoint broad areas in the genome that may be predictive or causative for specific diseases.
Karlsson, Morrill and their colleagues applied this same strategy to correlate areas of the canine genome with certain behavioral traits or characteristics. Pet owners who participate in Darwin’s Dogs provide scientists with saliva samples from their dogs. Researchers run whole genome sequencing on these samples to generate a robust genetic data set for investigation. Additionally, for this study, owners filled out 12 short surveys totaling 117 questions about their pet’s behaviors and physical traits. Combined, this data provides the basis for scientists to associate genetics with owner-reported behavior.
“Given a large enough sample size, GWAS are a really powerful tool for learning about genetics,” said Morrill. “We only get that size by looking at all dogs – not just purebred dogs, but mixed-breed dogs too. We compare all these DNA sequences computationally, using complex algorithms, to identify areas of differences and commonalities that might be of interest.”
Karlsson and Morrill collected more than 2,000 canine genomes and 200,000 survey answers through Darwin’s Dogs. Because of existing stereotypes about dog behavior and breeds, Karlsson and Morrill designed the study to account for possible owner bias, in part, by establishing standard definitions for reporting and rating canine behavioral traits such as biddability (a dog response to human direction), dog-human sociability (a dog’s comfort with people, including strangers) and toy-directed motor patterns (a dog’s interest and interaction with toys), among others. Physical and aesthetic trait standards were pulled from those published by the American Kennel Club.
Genetic research pegs the change from wolf to dog at about 10,000 to 15,000 years ago. Photo courtesy of Noah Snyder-Mackler
More to behavior than just breed
Behavioral data was analyzed across owner-reported breeds and genetically detected breed ancestries. The results of these tests, which included data from 78 breeds, showed that while breed explained some minor variation in behavior, its contributions were relatively small (9%). For certain behavioral traits, such as toy-directed motor patterns, age was a better predictor of behavior: Younger dogs were more likely to score higher in this category. For specific survey items, such as “lifts leg to urinate,” a dog’s sex was the best predictor of behavior. Physical traits like coat color were more than five times more likely to be predicted by breed than behavioral traits.
Additionally, investigators failed to find behaviors that were exclusive to any one breed. Even in Labrador retrievers, which had the lowest propensity for howling, 8% of owners reported their Labradors sometimes howl. Likewise, while 90% of greyhound owners reported that their dogs never bury their toys, three owners described greyhound dogs as frequent buriers.
Complementing the survey analysis of breeds to measure breed-behavioral propensities, the researchers also leveraged the genetic ancestry of highly mixed-breed dogs to test whether behavior is heritable in a breed-dependent manner. In some cases, heritable behavioral traits like biddability are somewhat more likely to correlate with breed, even if mixed a few generations back. In the case of purebred dogs, ancestry can make behavioral predictions somewhat more accurate. For less heritable, less breed-differentiated traits, like agonistics threshold, which measures how easily a dog is provoked by frightening, uncomfortable or annoying stimuli, breed is almost useless as a predictor of behavior.
A comparison of dog genomes was performed to identify genetic variations tracking along breed, as well as along individual physical and behavioral traits. Karlsson and Morrill identified 11 locations on the dog genome strongly associated with behavioral differences, none of which were specific for breed, and another 136 suggestively associated with behavior. The genetic differences between breeds such as golden retrievers, Chihuahuas, Labrador retrievers, German shepherd dogs and others, primarily affected genes that control coat color, fur length and other physical traits — far more than breed differences affected behavioral genes.
Overall, Karlsson and Morrill found that behavioral characteristics were influenced by multiple factors, including environment and individual genetics, but that modern breed classification played a modest role in the outcome.
“The majority of behaviors that we think of as characteristics of specific modern dog breeds have most likely come about from thousands of years of evolution from wolf to wild canine to domesticated dog, and finally to modern breeds,” said Karlsson. “These heritable traits predate our concept of modern dog breeds by thousands of years. Each breed inherited the genetic variation carried by those ancient dogs, but not always at exactly the same frequencies. Today, those differences show up as differences in personality and behavior seen in some, but not all, dogs from a breed.”
Next up: Understanding 'dog years'
For ASU's Snyder-Mackler, the study represents a significant opening salvo demonstrating the power of using modern genomic tools to study companion animals to gain new insights into the causes and consequences of variation in the social environment, from the molecular to the organismal levels.
"This study would not have been possible without the Herculean efforts to generate a massive behavioral dataset and combine that with whole genome sequencing of almost 2,000 dogs – without spending an arm and a leg. This was achieved by using some really cool computational approaches to try and gain as much information from each dog with as little sequencing as possible, which we found worked better than the most common approach to genotyping — microarrays," said Snyder-Mackler. His lab focuses on studies that allow him to probe questions central to human health, aging and evolutionary biology, often using companion animals or field animal research.
Next up is another huge citizen science canine effort now underway called the Dog Aging Project, where, according to Snyder-Mackler, "We are trying to understand what makes dogs tick (and age). Our lab uses molecular tools to try and identify how age and the environment interact to alter the dog immune system. So this new study has provided a really powerful roadmap to carrying out future studies in larger cohorts, which Dr. Karlsson is leading as part of the Dog Aging Project."
The project promises to explore what exactly are "dog years," other than the conventional wisdom of one dog year equal to about seven human years. What is known is that big dogs typically age more rapidly, an estimated 10 times faster than humans. By contrast, little dogs have a longer life span and can often live up to 20 years old.
Given that dogs share the human environment and have a sophisticated health care system but are much shorter-lived than people, they offer a unique opportunity to identify the genetic, environmental and lifestyle factors associated with healthy life span.
Snyder-Mackler and collaborators outlined the goals of their efforts in a recent Nature paper . The Dog Aging Project is an interdisciplinary, open-data, community science project that consists of a team of more than 100 staff, students, faculty and veterinarians from more than 20 academic institutions, along with over 30,000 canine participants and their owners.
The study investigators also include Kate E. Creevy, Joshua M. Akey, Matt Kaeberlein and Daniel E. L. Promislow, and afford great opportunities for Snyder-Mackler lab ASU graduate students, such as Brianah McCoy and Layla Brassington, who are helping to lead efforts to better understand the role of the environment, diet, drugs and the epigenome on dog aging.
"I wanted to work at the interface of the public and academic science, and the Dog Aging Project is a great way to do that. So I hopped on the project," said Mccoy, who is a nontraditional student and among the first ASU Online students to pursue a PhD, having spent some time at the National Institute of Aging and Harvard Medical School prior to joining the Snyder-Mackler lab. Mccoy is particularly interested in diet and longevity, and is studying a subset of participating dogs that will be selected to be part of a new clinical study to explore the potential of the drug rapamycin to improve health.
Brassington is a master's degree student now in the molecular and cellular biology program at ASU who hopes to graduate in winter 2022.
"I read about the Dog Aging Project, and I was super excited to find a project that looked at health-related changes due to the environment," she said. She will be examining the environmental air quality and pollution levels of ozone, carbon monoxide and others nationwide.
Both are now working hard with the citizen science effort, generating experiments, and hope to publish their first data from the Dog Aging Project later this year.
The Dog Aging Project is actively looking for more participants. If you are a dog owner wanting to get involved, you can learn more at dogagingproject.org.
Written by Jim Fessenden, UMass Chan Medical School Communications, with contributions from Joe Caspermeyer, ASU.
Top photo: Kristoff, one of Sparky's Service Dogs , keeps watch at the feet of his handler Taylor Randle on Hayden Lawn on Sept. 8, 2016, as they hang out with other puppies being trained by students. Photo by Charlie Leight/ASU News
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Arizona State University professors Anne Feldhaus and Carlos Vélez-Ibáñez are among those newly elected to the American Academy of Arts and Sciences, one of the oldest learned societies in the United States. Others elected this year include author Salman Rushdie, biochemist Katalin Karikó, actress Glenn Close, musician Rhiannon Giddens, The New York Times critic Wesley Morris and astronaut Ber...
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2 ASU faculty members elected to American Academy of Arts and Sciences
Anne feldhaus, carlos vélez-ibáñez are honored for achievements.
Arizona State University professors Anne Feldhaus and Carlos Vélez-Ibáñez are among those newly elected to the American Academy of Arts and Sciences, one of the oldest learned societies in the United States. Others elected this year include author Salman Rushdie, biochemist Katalin Karikó, actress Glenn Close, musician Rhiannon Giddens, The New York Times critic Wesley Morris and astronaut Bernard A. Harris.
“We are celebrating a depth of achievements in a breadth of areas,” said David Oxtoby, president of the academy. “These individuals excel in ways that excite us and inspire us at a time when recognizing excellence, commending expertise and working toward the common good is absolutely essential to realizing a better future.”
The American Academy of Arts and Sciences was founded in 1780 by John Adams, John Hancock and other leaders of the time to honor excellence and convene leaders to examine new ideas, address issues of importance to the nation and the world, and advance the public good. Since then, the organization has grown to include more than 13,500 members, recognizing several faculty and leaders from ASU.
“Election to the American Academy of Arts and Sciences is a meaningful recognition of the influence, impact and leadership a scholar demonstrates in their area of study,” said Michael M. Crow, president of ASU and himself a 2021 AAAS electee . “Distinguished Foundation Professor Feldhaus and Regents Professor Vélez-Ibáñez are consistent innovators in their respective fields who pioneer interdisciplinary research that incorporates cultural and anthropological approaches to learning and understanding. Their recognition is truly well-deserved.”
Feldhaus is a Distinguished Foundation Professor of religious studies at the School of Historical, Philosophical and Religious Studies with a research focus on the Marathi-language region of western India – of its religions, languages, oral traditions and literature, ranging from medieval bhakti to contemporary popular Hindu devotion.
“I am delighted to have my work recognized in this way. Over my decades at ASU, The College of Liberal Arts and Sciences, the religious studies department and the School of Historical, Philosophical and Religious Studies have been tremendously supportive of my research in India. I am grateful to my colleagues here at ASU as well as to the various funding agencies that have made my work possible,” said Feldhaus.
She has been the recipient of Fulbright-Hays, Guggenheim and Alexander von Humboldt fellowships as well as collaborative grants from the National Endowment for the Humanities. In 2017, Feldhaus was named Association for Asian Studies president-elect, the first ASU faculty member to be elected to the association’s highest office.
“During her four decades at ASU, Professor Feldhaus had a phenomenally productive scholarly career, producing (as author, editor or translator) more than 20 scholarly books – including recently ‘Say to the Sun “Don’t Rise” and to the Moon ”Don’t Set”: Two Oral Epics from the Countryside of Maharashtra‘ (Oxford University Press, 2014) – and winning numerous awards,” said Richard Amesbury , director of the School of Historical, Philosophical and Religious Studies. “Her election to the academy is well-deserved recognition of a career of uncommon brilliance.”
Vélez-Ibáñez is founding director emeritus of ASU's School of Transborder Studies and Regents Professor in both that school and the School of Human Evolution and Social Change . Among his many accolades, in 2016 he was inducted as a corresponding member of the Mexican Academy of Sciences, the first foreign anthropologist selected. In 2021, he received the Solon T. Kimball Award for Public and Applied Anthropology, recognizing over 50 years of contributions to the fields of cultural ecology, migration and transborder studies.
“I am deeply moved by this election and the opportunity to be part of a remarkable association of thinkers, artists and scholars who reflect by their election the imperative changes that the academy has undergone since the early founders – representing one small slice of the then-early republic to one welcoming and embracing a diversity of important narratives and their populations,” said Vélez-Ibáñez. “I especially welcome the recognition as one encompassing our School of Transborder Studies, which has been at the forefront of creating new and different approaches to seemingly intractable academic and human issues. As well, I am most grateful to be joining the ranks of my colleagues like Jane Buikstra, Magdalena Hurtado, Joan Silk and others in the School of Human Evolution and Social Change. These last two years have been quite a ride.”
Feldhaus and Vélez-Ibáñez are two of 261 individuals who have been elected to the academy in 2022. They join a rich history of thousands of members recognized by the academy for their scholarship, leadership and impact.
“We are incredibly proud of Foundation Professor Anne Feldhaus and Regents Professor Carlos Vélez-Ibáñez for the prestigious honor of being elected to the American Academy of Arts and Sciences,” said Patrick Kenney , dean of The College of Liberal Arts and Sciences . “I am confident that both individuals will use this esteemed opportunity to shape ideas and influence policy in areas of the arts, democracy, education, global affairs and science.”
For a complete list of new American Academy of Arts and Sciences members, visit the organization’s website .
Lauren Whitby contributed to this story. Top photo of Coor Hall on the ASU Tempe campus by Max Conacher
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Genetic research confirms your dog’s breed influences its personality — but so do you
Postdoctoral researcher, University of Sydney
Melissa Starling owns Creature Teacher, an animal behaviour consulting business.
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Over thousands of years of firm friendship between humans and dogs, we have successfully created about 350 different breeds. We’ve relied on terriers for hunting, sheepdogs for herding, and all for companionship – but how much are dog personalities defined by their breed?
In a new paper , researchers from the United States zoomed into the genetic codes of more than 4,000 different dogs, and surveyed 46,000 pet owners. They identified many genes associated with behaviours typical of certain breeds, such as the tendency for terriers to catch and kill prey.
Their findings ultimately suggest the type of breed does indeed explain many aspects of a dog’s unique personality.
But dog owners also play an enormous role in shaping their dog’s personality – such as whether they’re playful, tolerant of others, attention-seeking or quick to bark. So let’s take a closer look at how you can raise a good canine citizen.
What the research found
Dog breeds are a fascinating window into selective breeding, and some behaviour patterns we see in different breed groups – for example, herding and retrieving – are difficult to explain. The new US paper gives us hints as to how some of those patterns may have emerged.
The researchers analysed DNA samples from more than 200 dog breeds. Based on DNA data, they managed to whittle these down to ten major genetic lineages, including terriers, herders, retrievers, sighthounds, scenthounds, and pointers/spaniels.
Each lineage corresponds to a category of breeds historically used for tasks, such as hunting by scent versus sight or herding versus protecting livestock.
This means breeds that are not closely related, but bred for the same purpose, may share common sets of genes. This has been very difficult to show in the past.
For example, the paper identifies herding breeds, such as Kelpies or border collies, as characterised by high “non-social fear”, which is fear of environmental stimuli such as loud noises, wind or vehicles. Terriers, such as Jack Russells, are characterised by high predatory chasing. And scenthounds, such as Beagles, by low trainability.
These align with what these dogs were bred for: herding breeds for their high environmental awareness and sensitivity, terriers for chasing and killing prey, and scenthounds for their independent focus on non-visual signals (scent).
Read more: Is your dog happy? Ten common misconceptions about dog behaviour
The researchers take a more detailed look at herders, because of their easily identifiable and usually innate behaviour of herding.
Interestingly, the gene found to be common among sheepdogs – called EPHA5 – has also been associated with anxiety-like behaviours in other mammals, as well as attention-deficit/hyperactivity disorder (ADHD) in humans. The researcher team says this might explain the breed’s high energy and tendency to hyperfocus on tasks.
What dog owners need to know
The fact dog behaviour varies with breed has generally been accepted among researchers for a while, to varying degrees. But it’s important not to discount how a dog’s upbringing can also shape their personality.
In fact, a different genetic study earlier this year suggested that while a dog’s lineage is one influencer of behaviour, it’s probably not the most important.
Those researchers stress that dog behaviour is influenced by many different genes that existed in dogs before breeds were developed, and these genes are present in all breeds. They argue modern breeds are mainly distinguished by their looks, and their behaviour is likely more heavily influenced by environmental factors such as upbringing and learning history, than genetics.
Read more: Profound grief for a pet is normal – how to help yourself or a friend weather the loss of a beloved family member
So what does that mean for dog owners? Well, while a dog’s behaviour is influenced by its breed, there’s much we can do to shape a good canine companion.
This work is particularly important over the first one to two years of a dog’s life, starting with early socialisation when they’re puppies. They should be exposed to all the stimuli we want them to grow up accepting, such as kids, vehicles, other animals, pedestrian malls, weekend sport, travelling and grooming.
We then need to continue training and guiding dogs to behave in ways that keep them and others safe as they grow up. Just as human children and teenagers need guidance to learn how to make good decisions and get along with others, so our dogs need the same guidance through adolescence to adulthood (usually around age two).
While breed alone might not be a good predictor of the behaviour for any individual dog, it’s certainly sensible to pay attention to what breeds were originally bred for. The new study supports that sentiment. Those behavioural patterns that helped dogs do their original job for humans are probably still strong in the population.
That means if you already own backyard chickens or pocket pets such as rabbits, think carefully before adopting a terrier, and plan what you’ll do if the terrier wants to hunt your small animals.
If you live in the city or an apartment block where the environment is constantly busy, this is likely to be very challenging for a herding breed. And if you want a dog super responsive to you, scenthounds are probably not a great bet.
Selecting a dog that will work well with your lifestyle is a probability game. It’s perfectly possible to find a very responsive and trainable scenthound, or a terrier that can live peacefully with, for instance, pet rats.
But if that’s something you specifically need from a dog, play the odds by starting with a breed developed for that lifestyle. Then pour lots of time and effort into socialisation and training.
Dogs are mostly what we make of them, and they repay the effort we put into their behaviour tenfold.
Read more: How hot is too hot? Here's how to tell if your dog is suffering during the summer heat
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Original research article, assisting decision-making on age of neutering for 35 breeds of dogs: associated joint disorders, cancers, and urinary incontinence.
- 1 Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
- 2 Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
- 3 Department of Statistics, University of California, Davis, Davis, CA, United States
Neutering (including spaying) of male and female dogs in the first year after birth has become routine in the U.S. and much of Europe, but recent research reveals that for some dog breeds, neutering may be associated with increased risks of debilitating joint disorders and some cancers, complicating pet owners' decisions on neutering. The joint disorders include hip dysplasia, cranial cruciate ligament tear or rupture, and elbow dysplasia. The cancers include lymphoma, mast cell tumor, hemangiosarcoma, and osteosarcoma. In previous studies on the Golden Retriever, Labrador Retriever and German Shepherd Dog, neutering before a year of age was associated with increased risks of one or more joint disorders, 2–4 times that of intact dogs. The increase was particularly seen with dogs neutered by 6 months of age. In female Golden Retrievers, there was an increase in one or more of the cancers followed to about 2–4 times that of intact females with neutering at any age. The goal of the present study was to expand and use the same data collection and analyses to cover an additional 29 breeds, plus three varieties of Poodles. There were major breed differences in vulnerability to neutering, both with regard to joint disorders and cancers. In most cases, the caregiver can choose the age of neutering without increasing the risks of these joint disorders or cancers. Small-dog breeds seemed to have no increased risks of joint disorders associated with neutering, and in only two small breeds (Boston Terrier and Shih Tzu) was there a significant increase in cancers. To assist pet owners and veterinarians in deciding on the age of neutering a specific dog, guidelines that avoid increasing the risks of a dog acquiring these joint disorders or cancers are laid out for neutering ages on a breed-by-breed and sex basis.
In the U.S. and much of Europe, the practice of neutering male and spaying female dogs (herein both referred to as neutering) has become routine ( 1 ) and is increasingly being performed at, or before, 6 months of age. At the same time, several investigations have revealed that joint disorders and some cancers may increase in association with neutering of males and/or females. For example, in studies that did not focus on specific breeds or ages of neutering, one found that hip dysplasia and cranial cruciate ligament tears or ruptures were significantly more likely in neutered than intact males and females ( 2 ). Another study found that neutering was associated with a 3-fold increase in excessive tibial plateau angle ( 3 ), which is a risk factor for development of cranial cruciate ligament tears or rupture. Neutering is reported to be a risk factor for canine intervertebral disc herniation in Dachshunds ( 4 ). Certain cancers are also known to be more likely in neutered than intact dogs. The occurrence of lymphoma was found to be higher in spayed than intact females ( 5 ), as was the occurrence of mast cell tumors ( 6 ) and hemangiosarcoma ( 7 ). A study of over 40,000 dogs utilizing the Veterinary Medical Database found that neutered males and females were more likely to die of cancer than intact dogs ( 8 ). A recent finding was that the absence of estrogen from spaying females was associated with accelerated brain aging ( 9 ). Another recent report from the Golden Retriever Lifetime Project is that neutering at <6 months increases the risk of cranial cruciate ligament injury ( 10 ). Most of the studies cited above offer no useful clinical information or guidelines with regard to the various diseases that may occur in association with neutering in a specific breed.
In an attempt to address the absence of breed-specific information on joint disorders and cancers associated with neutering, we undertook a project focusing on various specific breeds using data collection and analyses with our extensive veterinary hospital database where the same diagnostic criteria could be applied to all breeds. We started with popular breeds well-represented in the database, initially with the Golden Retriever ( 11 , 12 ), Labrador Retriever ( 12 ) and German Shepherd Dog ( 13 ). The joint disorders examined included cranial cruciate ligament tears or rupture (CCL), hip dysplasia (HD) and elbow dysplasia (ED). The cancers examined, which previous studies found could be affected by neutering, were lymphoma/lymphosarcoma (LSA), hemangiosarcoma (HSA), mast cell tumors (MCT), and osteosarcoma (OSA).
In the Labrador Retrievers, Golden Retrievers, and German Shepherd Dogs, there was an increase in the incidence of one or more of the joint disorders with neutering in the first year in males and females to 2–4 times >3–5% incidence in intact dogs. In female Golden Retrievers, neutering at any age was associated with an occurrence of one or more of the cancers followed to 2–4 times higher than the 5 percent incidence in intact females. But in male Golden Retrievers, and in male and female Labrador Retrievers and German Shepherd Dogs, there was no evident increase in cancers above that of the dogs left intact. Preliminary analyses from some small-dog breeds revealed no apparent increased risks of joint disorders with neutering. Thus, the research that had been undertaken revealed a wide range of breed-specific differences in disease vulnerability to neutering.
The purpose of this study was to analyze, in a variety of additional breeds, the increased risks, if any, of the above specified joint disorders and cancers associated with neutering male and female dogs at various ages, so as to increase the information available to pet owners and veterinarians for consideration when making decisions regarding neutering specific dogs. We added 29 new breeds to the study, separating three varieties of Poodles, for a total of 32 breed groups (referred to as breeds); this made a total of 35 breeds with the Goldens, Labs and German Shepherds included. The goal was to use the same veterinary hospital database and diagnostic criteria for the diseases as was used with the published studies on the retrievers and German Shepherds so as to allow for direct comparisons among various breeds. The primary purpose was to offer readers some evidence-based information on breed-specific differences with vulnerability to neutering, including suggested guidelines for neutering ages to avoid increasing long-term health risks of neutering, if any. A secondary, unforeseen, purpose was to document breed-specific differences in the increases in some cancers associated with removal of gonadal hormones, as an area for possible research on genetic aspects of cancer occurrence.
Hospital records of the Veterinary Medical Teaching Hospital (VMTH) provided the retrospective dataset used. In conformity with the campus policy, faculty of the University of California-Davis, School of Veterinary Medicine, are allowed use of the record system for research purposes. No animal care and use committee approval was required, and strict confidentiality of the owners and their dogs was maintained.
Subjects Breed Categories
In addition to the Golden Retriever, Labrador Retriever, and German Shepherd Dog, the other breeds chosen for this project included those most frequently occurring in the database and those chosen to obtain a sampling of giant breeds or small-dog breeds. The final list of 35 (including three varieties of Poodle) represented in the present study are, alphabetically, the: Australian Cattle Dog, Australian Shepherd, Beagle, Bernese Mountain Dog, Border Collie, Boston Terrier, Boxer, Bulldog, Cavalier King Charles Spaniel, Chihuahua, Cocker Spaniel, Collie, Corgi (Pembroke and Cardigan combined), Dachshund, Doberman Pinscher, English Springer Spaniel, German Shepherd Dog, Golden Retriever, Great Dane, Irish Wolfhound, Jack Russell Terrier, Labrador Retriever, Maltese, Miniature Schnauzer, Pomeranian, Poodle-Miniature, Poodle-Standard, Poodle-Toy, Pug, Rottweiler, Saint Bernard, Shetland Sheepdog, Shih Tzu, West Highland White Terrier, and Yorkshire Terrier.
The present study examined the occurrence in both sexes of the joint disorders: HD, CCL and ED. Also examined in both sexes were the cancers LSA, HSA, MCT, and OSA, because these had been shown in some multi-breed studies to be increased in risks with neutering. In addition, mammary cancer (MC), pyometra (PYO), and urinary incontinence (UI) were examined in female dogs. Of interest was the possible association of early neutering and the occurrence of intervertebral disc disorders (IDD) in the Corgi and Dachshund, two breeds known to be at risk for these diseases. All of the above diseases were examined with regard to dogs neutered in one of the age periods of: <6 mo., 6–11 mo., 1 year (12 to <24 mo.) or 2–8 years, or left intact. The diseases were tracked until the dogs were last seen at the hospital, or through 11 years of age, if seen past their 12th birthday.
Mammary cancer is a late occurring cancer with the median age of diagnosis being 10.1 years in one study ( 14 ). Tracking cancers through 11 years of age would be presumably sufficient to catch most cases of MC if the case record had information extending to that age. However, most case records did not extend to that age. As an additional point of comparison, percentages of MC occurrence were looked at in just females tracked through 8 years of age or beyond, including diagnosed MC cases beyond the 12th birthday cut-off, which was the cut-off used for all other data.
Data Collection and Presentation
The computerized hospital record system of the VMTH provided the dataset. The hospital, with currently over 50,000 cases admitted per year, is a secondary and tertiary facility as well as being a primary care facility. The statistical evaluations, with standardized diagnostic criteria applied to various diseases and taking into account sex and different ages of neutering, required a large database with a computerized record system. The study focused on proportional differences in disease occurrences between the neuter age groups and intact dogs of the same breed and sex.
The study period represented 15 years of data for most breeds. The inclusion criteria were date of birth, age at neutering (if neutered), and age of diagnosis or onset of clinical signs for diseases of interest. As mentioned, age at neutering was designated as <6 mo., 6–11 mo., 1 year (12 to <24 mo.), and 2–8 years (2 to <9 years). The term “early neutering” is sometimes used below to refer to neutering in the first year, combining cases for both the <6 mo. and 6–11 mo. neuter periods. For MC, PYO, and UI, only females were examined. While UI does occur in males, it is predominantly an issue in females.
For all neutered dogs that developed a disease of interest, records were examined to confirm that the dog was neutered prior to the diagnosis or signs of the disease. If the dog developed signs of the disease prior to neutering, the dog was considered intact for analysis of that disease. However, for any disease that occurred after neutering, the dog was considered neutered for analysis of that disease. For any disease of interest that occurred before 12 months of age, the dog was removed from that disease analysis, but included in analyses of other diseases. Therefore, the number of cases for various diseases varied in the analyses for different disease occurrences.
The age at neutering was sometimes not included in the hospital records, so telephone calls to the referring veterinarians were made to obtain the neutering dates or ages. Nonetheless, there were many neutered dogs where age at neutering was not available from the VMTH records or the referring veterinarian, so these dogs were excluded from the study. Of course, this was not an issue with the sample of intact dogs, so there were proportionately more intact cases in the final dataset for each breed than would be expected in the general population. However, the proportion of dogs with a disease, whether intact or neutered, was not affected by the overrepresentation of intact dogs in the database.
The criteria for disease diagnoses were the same as in previous studies on the retrievers and German Shepherd Dog ( 11 – 13 ). A dog was considered as having a disease of interest if the diagnosis was made at the VMTH, or by a referring veterinarian and later confirmed at the VMTH. For joint disorders (HD, ED, and/or CCL), dogs typically presented with signs of lameness, difficulty in moving, and/or joint pain. The diagnosis was confirmed by orthopedic examination, radiographic evidence, and/or surgery. In Dachshunds and Corgis, where intervertebral disc disorders (IDD) is a concern, the diagnosis included herniation, rupture, extrusion, protrusion, fracture, compression, stenosis, or spinal cord injury. For cancers (LSA, HSA, MCT, OSA, MC), the diagnosis was based on the presence of a tissue mass, lumps on the skin or enlarged lymph nodes, and confirmed by chemical panels, appropriate blood cell analyses, imaging, histopathology, and/or cytology. PYO was confirmed by ultrasonic evidence and/or post-surgically after removal of the uterus. UI was confirmed by clinical signs of abnormally frequent urination, urinalyses and exclusion of urinary tract infection and/or other disease. If a diagnosis was listed in the record as “suspected” based on some clinical signs but not confirmed, the case was excluded from the analysis for that specific disease, but the dog was included in other disease analyses.
Although body condition scores have been reported to be a factor in the occurrence of joint disorders ( 3 , 15 ), our previous studies on the retrievers and German Shepherd Dog found no significant relationship when body condition scores were compared between dogs with and without a joint disorder. Therefore, in the current paper the body condition score is not reported for each breed.
Survival analysis was used to test for differences with respect to the hazard of a disease in the neutered and intact groups, while adjusting for the differences in time at risk for a disease. The groups were initially compared using a Kaplan Meier life table analysis. Post-hoc comparisons among the subgroups were based on least squares means of the hazard within each subgroup. For comparisons where the Kaplan Meier test showed significance at the p <0.05 level, both the log-rank and Wilcoxon tests were used for further analyses. Because joint disorders are expected to be seen at a similar risk throughout a dog's lifespan, regardless of age, the log-rank test was used initially for the joint disorders. If the log-rank test did not show significance but the Wilcoxon test did for joint disorders, the Wilcoxon test result was reported with significance level and an asterisk. The reverse rule of thumb was used with cancers where the first test examined was the Wilcoxon test, since the risk of cancer is expected to be higher in older dogs. If the Wilcoxon test did not show significance but the log-rank test did for cancers, the log-rank test result was reported with significance level and an asterisk. For all statistical tests, the two-tailed statistical level of significance was set at p <0.05 and reported as either p < .05 or p <0.01. Each breed was analyzed separately, and there were no statistical comparisons between breeds. However, the overall findings with each breed allow for some general comparisons.
For each breed represented on a separate page in Appendix 1 , the numbers of intact and neutered males and females are given. In the tables, the percentage of dogs with each of the diseases and the percentage having at least one of the joint disorders and at least one of the cancers (except MC) was calculated for intact males and intact females as well as those neutered at various age ranges. Statistical analyses compared the occurrences of joint disorders and cancers between each neuter period and intact dogs. If the comparison was significant at either the p <0.05 or p <0.01 level, the data were bolded and the p -value was given. The detailed datasets are available online (Figshare, doi: 10.6084/m9.figshare.7231010 ). Three breeds for which findings have been previously published (Golden Retriever, Labrador Retriever, German Shepherd Dog) are included to present an overall picture in the same Appendix 1 . The data for these three breeds were expanded through 11 years of age, to provide continuity among breeds and diseases.
For each breed, a short paragraph summarizes the main findings on joint disorders (HD, CCL, ED), cancers (LSA, HSA, MCT, OSA) for both males and females, and MC, PYO and UI for females. For Dachshunds and Corgis, the occurrence of IDD is listed for both sexes. Survival analyses were not done on IDD occurrence because the condition represented so many different disease diagnoses. Also included in the breed summary information is a suggested guideline for neutering age for males and females to avoid increasing the risks of a disease under consideration. When there was no noticeable occurrence of an increase in joint disorders or cancers with neutering, the guideline statement was made that those wishing to neuter should decide on the appropriate age (or briefly stated as choice in Table 1 ). When neutering at <6 months was associated with an increased disease risk but no increased risk was evident with neutering beyond 6 months, the default recommended guideline was neutering beyond, 6 months.
Table 1 . Suggested Guidelines by Breed for Age of Neutering.
The breed-by-breed findings are presented in four different formats. One format, seen in this section below, is a short paragraph for each breed. The occurrence of the joint disorders and the cancers followed is reported for the intact and neutered dogs, and the increase in the two disease types over that of the intact dogs, if significant, is reported. Other findings are also mentioned if appropriate, such as IDD occurrence in Dachshunds and Corgis. A second format, represented in Table 1 , is a very brief summary of spaying and neutering guidelines based on findings regarding joint disorders and cancers for each breed, allowing the reader to quickly scroll through the various breeds. In the third format, the data-based findings, with statistical notations for each breed, are reported in Appendix 1 . In the fourth format, the raw data allowing the reader to perform their own calculations, if desirable, is available in Figshare.
The mean age of last entry was calculated for intact and neutered males and females for each breed and presented in Appendix 2 . Across all breeds the mean age of last entry in the record for neutered males was 5.5 years (range 3.71–6.54), for neutered females 5.7 years (range 4.21–6.97), for intact males 4.9 (range 4.15–7.11), and intact females 4.7 (range 3.41–6.32). Upon perusal of the data, it is evident that the mean age of data entry for intact dogs was younger than that of neutered dogs, especially for females, where there is disparity of almost 1 year. To address the issue of whether the lower age of last entry for intact dogs could have resulted in a lower rate of disease occurrence in intact dogs in either joint disorders or cancers, we examined data of dogs where the last entry was at 8 years or beyond. We looked at three breeds with the largest databases (Golden Retrievers, Labrador Retrievers, and German Shepherd Dogs) and where there were significant differences in disease diagnoses between early neutered and intact dogs. Using these parameters, the occurrences of joint disorders in Golden Retrievers for those neutered at ≤ 6mo. vs. intact, in males, there was a 6-fold difference (18% vs. 3%) and in females 3-fold (25 vs. 8%). For male Labrador Retrievers, the figures were 22 vs. 8% and in females 33 vs. 10%. For male German Shepherd Dogs, the figures were 33 vs. 2% and for females, 29 vs. 9%. For cancers in female Goldens, the figures were 26 vs. 14%. The incidence figures, although not sufficient for meaningful statistical analyses, are consistent with the larger database where all ages are included. Thus, while the age of the last visit is a limitation for analyses on late-occurring cancers and joint disorders, the examples chosen for dogs seen at the age of 8 years or beyond are consistent with the overall results presented here; these results appear to represent what would be seen in the general situation.
Looking at the occurrences of these joint disorders and cancers, it is clear that most breeds are unaffected for these diseases by age of neutering. Vulnerability to joint disorders associated with neutering is generally related to body size. Small-dog breeds – Boston Terrier, Cavalier King Charles Spaniel, Chihuahua, Corgi, Dachshund, Maltese, Pomeranian, Poodle-Toy, Pug, Shih Tzu, Yorkshire Terrier – do not appear to have an increased risk in joint disorders with neutering compared to the breeds of larger size. However, in the breeds of larger body size there were differences among the breeds with the two giant breeds – Great Danes and Irish Wolfhounds – showing no indication of increase in one or more joint disorders with neutering at any age.
Although the occurrence of MC was tracked, the female mean age at the last hospital visit for all breeds ended short of the reported, late-onset mean age of MC occurrence in intact female dogs. Thus, the low occurrence of MC in intact females (typically under 6 percent) cannot be expected to represent the actual incidence over a female's lifetime. When the percentage of MC was calculated for only those dogs seen through 8 years of age or older (including cases diagnosed past the 12th birthday), the results did not appear appreciably different than the percentages seen using the study age range. However, the number of dogs seen through age 8 or beyond was fairly small, so the analysis results might change with an increased sample size of these older dogs.
The following are brief summaries for each of the breeds along with suggested guidelines for age of neutering. See Appendix 1 for the complete data set, including statistical analyses for each breed.
Australian Cattle Dog
The study population was 61 intact males, 58 neutered males, 48 intact females, and 70 spayed females for a total of 237 cases. In this sample, 5 percent of intact males and 2 percent of intact females were diagnosed with one or more joint disorders. Neutering males was not associated with any increased risk in joint disorders, but there was an association with spaying females at <6 mo. where the risk of a joint disorder increased to 15 percent ( p <0.05). The occurrence of cancers was low for males and females left intact (0 and 3 percent, respectively). There were no evident occurrences of the cancers in dogs neutered at various ages. The occurrence of MC in intact females was 6 percent and in those spayed at 2–8 years, 6 percent. For females left intact, 4 percent were reported with PYO. UI was not reported in any of the spayed or intact females. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered males, those wishing to neuter should decide on the appropriate age. In females, the increased risk of a joint disorder with spaying occurred only at the <6 mo. range, so the suggested guideline is spaying at, or beyond, 6 months.
The study population was 93 intact males, 135 neutered males, 76 intact females, and 136 spayed females for a total of 440 cases. In this sample, 3 percent of intact males and 4 percent of intact females were diagnosed with one or more joint disorders. Neutering males and females was not associated with any evident increased risk in joint disorders. The occurrence of cancers was 9 percent for intact males and, in contrast, only about 1 percent for intact females. Neutering males did not appear to be associated with an overall increased risk of cancers above the rather high level of intact males. However, spaying females at 6–11 mo. and at 2–8 years was associated with a 7–8 percent risk in cancers which may have reached significance with a larger sample size. The occurrence of MC in intact females was zero, but was 8 percent in females spayed at 2–8 years. For females left intact, 5 percent were reported with PYO. UI was reported in just 1 percent of early-spayed females. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered males, those wishing to neuter should decide on the appropriate age. The guideline for females is the same while also maintaining vigilance for the cancers which may be associated with spaying beyond 6 months, or else leaving the female intact and being vigilant for MC.
The study population was 42 intact males, 82 neutered males, 45 intact females and 87 spayed females for a total of 256 cases. Just 2 percent of intact males were diagnosed with one or more joint disorders, but with neutering at 6–11 mo. joint disorders increased 7-fold to 15 percent, which may have reached significance with a larger sample size. None of the females left intact or spayed had a joint disorder. None of the intact males or females was diagnosed with any of the cancers followed. There was no evident increased occurrence of cancers in neutered males and females. There was no occurrence of MC in intact or late-spayed females. There was 1 case of PYO in intact females (2 percent). UI was reported in only 2 percent of early-spayed females.
For males, in light of a possible increase in joint disorders for those neutered at 6–11 mo., the suggested guideline is to delay neutering males until beyond a year of age. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered females, those wishing to neuter should decide on the appropriate age.
Bernese Mountain Dog
The study population was 59 intact males, 74 neutered males, 37 intact females, and 65 spayed females for a total of 235 cases. The percentage of intact males with at least one joint disorder was 4 percent and for intact females, 11 percent. Neutering males any time prior to 2 years of age was associated with a significant increase in at least one joint disorder to 23–24%, about a 6-fold increase over intact males ( p <0.01). Spaying females before 6 mo. increased the likelihood of a joint disorder to over 3-fold that of intact females, but this did not reach significance. The occurrence of one or more of the cancers followed was 9 percent for both intact males and intact females. There was no evident increase in cancer risk in males related to neutering, but with females, spaying at <6 mo. was associated with a 2-fold increase above that of intact females. There was no occurrence of MC in females, whether left intact or neutered at any age, and a 5 percent occurrence of PYO in intact females. There was no occurrence of UI in intact or spayed females. Reflecting the increased risk of joint disorders for males, the suggested guideline for neutering males is delaying neutering until well-beyond 2 years. Lacking a significant occurrence of increased joint disorders or cancers in neutered females, those wishing to neuter should decide on the appropriate age.
The study population was 105 intact males, 85 neutered males, 88 intact females, and 121 spayed females for a total of 399 cases. In this sample 2–3% of intact males and females were diagnosed with one or more joint disorders, and neutering males and females was not associated with any evident increased risk in joint disorders. The occurrence of one or more of the cancers followed in intact males was 2 percent and none for females left intact. For males, there was a significant increased risk in one or more of the cancers to 13 percent with neutering at 6–11 mo. ( p <0.05), and for females there was a significant increase in the cancers to 11 percent with spaying at 6–11 mo. ( p <0.01). The occurrence of MC in intact females was just 1 percent, and for PYO, 4 percent. UI was reported in just one spayed female. The suggested guideline for neutering, given the significant risk of cancers, is holding off neutering of both sexes until beyond a year of age.
The study population was 75 intact males, 67 neutered males, 54 intact females, and 96 spayed females for a total of 291 cases. None of the intact or neutered males or females was diagnosed with one or more joint disorders. For cancers, the story is a bit different in that 5 percent of intact males were diagnosed with one or more cancers and 10 percent of males neutered at <6 mo., and 12 percent of males neutered at 6–11mo. had cancers ( p <0.01, the two neuter periods combined). For females, 2 percent of intact females had one or more of the cancers and with spaying, there was no evident increase of cancers. The occurrence of MC in intact females was 2 percent and for PYO, 7 percent. UI was 2 percent in early-spayed females. In light of the significant increase in cancers in males with neutering through 11 months of age, the suggested guideline for males is delaying neutering to beyond a year of age. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered females, those wishing to neuter should decide on the appropriate age.
The study population was 220 intact males, 203 neutered males, 128 intact females, and 210 spayed females, for a sample size of 761 cases. Males and females left intact had just a 2 percent occurrence of joint disorders, with neutered males and females showing no apparent increase in this measure. The occurrence of one or more of the cancers followed in intact males was 17 percent, and for intact females, 11 percent. Neutering males before 2 years significantly raised the risk of a cancer over that of intact males to 32 percent ( p <0.01). The same pattern of increase in cancers was seen in spaying females with up to 20 percent of females having one or more of the cancers with spaying done before 2 years, an increase that was not significant, but with an expanded database may have been. There was no occurrence of MC in intact females. PYO was diagnosed in 2 percent of intact females. Just 1 percent of spayed females were diagnosed with UI. Given the risk of increased cancers, the suggested guideline for both sexes is to delay neutering until beyond 2 years of age.
The study population was 198 intact males, 156 neutered males, 90 intact females, and 114 spayed females for a sample of 558 cases. The occurrence of joint disorders in intact males was 7 percent and 5 percent in intact females. Neutering at <6 mo. raised the incidence to 15 percent for males and to 18 percent for females, which did not reach significance for either. The cancers followed occurred at the 6 to 7 percent level in intact males and females. There were no significant increases above this with neutering males or females. The occurrence of MC in females left intact was 1 percent and 2 percent with spaying at 2–8 years. There was a 2 percent occurrence of PYO in intact females and no UI in early spayed females. Lacking a significant occurrence of increased joint disorders or cancers in neutered males or females, those wishing to neuter should decide on the appropriate age, but some people may wish to be cautious in view of the possible apparent risk in joint disorders.
Cavalier King Charles Spaniel
The study population was 51 intact males, 72 neutered males, 87 intact females, and 76 spayed females, for a sample size of 286 cases. For males and females left intact, the occurrences of one or more joint disorders were just 4 and 1 percent, respectively, and for both sexes neutering was not associated with any increase in this measure. The occurrences of cancers in intact males were 2 percent and zero for intact females. For both sexes neutering was not associated with any increase in this measure. The occurrence of MC in females left intact was zero. The occurrence of PYO was 2 percent in intact females. There was no occurrence of UI in spayed females. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered males or females, those wishing to neuter should decide on the appropriate age.
The study population was 261 intact males, 189 neutered males, 298 intact females, and 289 spayed females for a total sample of 1,037 cases. For both males and females, neither those left intact, nor those neutered at any age had a noteworthy occurrence of a joint disorder. The cancers followed in both intact and neutered males and females were <5 percent with no evident increase with neutering at any age. The occurrence of MC in females left intact was 1 percent, and in females neutered at 2–8 mo., 4 percent. In intact females, PYO was diagnosed in 2 percent. There was no UI diagnosed in any of the spayed females. Lacking a noticeable occurrence of increased joint disorders or cancers with neutering in either sex, those wishing to neuter should decide on the appropriate age.
The study population was 71 intact males, 112 neutered males, 61 intact females, and 127 spayed females, for a sample size of 369 cases. The occurrence of at least one joint disorder was seen in 1 to 3 percent of the intact males and females. Neutering males at <6 mo. was associated with a significant increase of this measure to 11 percent ( p <0.01). Spaying females was not associated with an increase in joint disorders. The occurrence of one or more of the cancers followed was 6 percent in intact males with no increase with neutering. Although there was no occurrence of cancers in intact females, this measure rose significantly to 17 percent in females spayed between 1 and 2 years of age ( p <0.01), entirely due to MCT. For females left intact, 11 percent were diagnosed with MC and 5 percent with PYO. None of the spayed females developed UI. The suggested guideline for males is neutering beyond 6 months of age. Given the increased cancer risk for females spayed at a year of age, the suggested guideline is delaying spaying until beyond 2 years of age.
The study population was 29 intact males, 26 neutered males, 24 intact females, and 37 spayed females, for a sample size of 116 cases. The occurrence of at least one joint disorder was seen in 7 percent of the intact males and in none of the intact females. None of the neutered males or females had a noteworthy occurrence of a joint disorder. The occurrence of one or more of the cancers followed was 11 percent for intact males and none for the intact females. There was no evident increase of cancers in males with neutering, and in females, there was an increase of cancer to 40 percent in those spayed at <6 mo., which may have reached significance with a larger sample size. For females left intact, 4 percent were diagnosed with MC, and 16 percent were diagnosed with PYO. Of females spayed at 6–11 mo., 13 percent had UI. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered males, those wishing to neuter a male should decide on the appropriate age. For females, given the apparent risks of cancers with spaying at <6 mo. and UI with spaying at 6–11 mo., the guideline is to delay spaying until the female is a year old.
Corgi (Welsh), Pembroke and Cardigan
The study population was 42 intact males, 78 neutered males, 50 intact females, and 70 spayed females, for a total sample size of 240 cases. Although these are two breeds, they vary only a little in size, so these two breeds are combined for statistical analyses and display of data. The occurrence of at least one joint disorder in intact males was 5 percent and for intact females 6 percent. There was no significant increase in this measure in males or females with neutering. This is one of the breeds where intervertebral disc disorders are a concern, and in 3 percent of intact males and 8 percent of intact females, IDD was reported. In males neutered before 6 months, the occurrence of IDD reached 18 percent, and in females there was no increase with neutering. The occurrence of one or more of the cancers followed was 5 percent in intact males and 6 percent in intact females. In neutered males and females, there was no evident increase in cancers. For females left intact, the occurrence of MC was 8 percent, and there was zero occurrence of PYO. There was no diagnosis of UI in spayed females. The suggested guideline for age of neutering for males, given the increase in IDD with neutering at <6 mo., is beyond 6 months. Lacking a noticeable occurrence of increased joint disorders, IDD, or cancers with neutering females, those wishing to neuter a female should decide on the appropriate age.
The study population was 177 intact males, 170 neutered males, 99 intact females, and 212 spayed females, for a total sample size of 658 cases. Joint disorders were basically absent in males and females, left intact or neutered. This is a breed plagued by intervertebral disc disorders, and in this sample 53 percent of intact males and 38 percent of intact females were diagnosed with a form of IDD. There was no evident increase in this measure with neutering of males or females. The occurrence of the cancers followed was <1% in both intact males and females, with no indication of an increased risk with neutering. For females left intact, the occurrence of MC was 1 percent and for PYO, 4 percent. None of the spayed females developed UI. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered males or females, those wishing to neuter should decide on the appropriate age.
The study population was 109 intact males, 91 neutered males, 53 intact females, and 108 spayed females, for a sample size of 358 cases. The percentage of intact males with at least one joint disorder was 2 percent and 0 percent for intact females. There was no evident increase in this measure with neutering males. For females, spaying within 11 months resulted in an increase in joint disorders of 11 percent, which did not reach significance. The occurrence of one or more of the cancers followed for both intact males and intact females was 2 percent. In neutered males at the 1 year and 2–8 year periods, there was a non-significant increase in occurrence of cancers to 6 percent and 13 percent, respectively. For females, there was no noteworthy increase in cancers with spaying at any time. The occurrence of MC in females left intact was 2 percent and 4 percent for those spayed at 2–8 years. There was a 7 percent occurrence of PYO in intact females. UI was a significant risk in females spayed at any age up to 2 years, ranging from 25 percent in the females spayed at <6 mo. ( p <0.01) to 19 percent for those spayed between 1 and 2 years ( p <0.05). The suggested guideline, based on fragmentary results, for males is to leave the male intact or neuter before 1 year of age to avoid the possible increased risk of cancers seen in those neutered beyond a year of age. For females, the suggested guideline, also based on limited data, given the risk of UI in early spayed females, and the possible increased risk of a joint disorder, is to consider delaying spaying until beyond 2 years of age.
English Springer Spaniel
The study population was 52 intact males, 57 neutered males, 37 intact females, and 66 spayed females for a total sample of 212 cases. In males and females left intact, the occurrence of one or more joint disorders was 5 and 8 percent, respectively. Among males and females neutered at various ages, there were no noteworthy increases in joint disorders. The cancers followed occurred in the intact males and females at a 6 percent level, and neutering at any age was not associated with any evident increase in this measure in either sex. In intact females, MC was diagnosed in 6 percent, and for those spayed at 2–8 years, 15 percent. PYO was not reported in any of the intact females. Spaying females at 6–11 mo. was associated with a 13 percent occurrence of UI, which may have reached significance with a larger sample size. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered males, those wishing to neuter should decide on the appropriate age. For females, given the increased risk of UI in those spayed before 1 year, the suggested guideline is to delay spaying until a year of age.
German Shepherd Dog
The study population was 514 intact males, 272 neutered males, 173 intact females, and 298 spayed females for a total of 1,257 cases. In males and females left intact, the occurrence of one or more joint disorders was 6 and 5 percent, respectively. Neutering males at <6 mo., 6–11 mo. and 1–2 years was associated with increased risks of this measure to 19, 18 and 9 percent, respectively ( p <0.01). Spaying females at <6 mo. and 6–11 mo. was associated with a 20 and 15 percent level of increased risk ( p <0.01), and spaying at 1–2 years with a 5 percent risk level ( p <0.05). The occurrence of one or more of the cancers followed for intact males and females was 3 percent and 2 percent, respectively. Neutering at the various ages was not associated with any appreciable increased risk in cancers followed. The occurrence of MC in intact females was 5 percent and for those spayed at 2–8 years, 6 percent. Of intact females, 3 percent were reported with PYO. UI ranged up to 9 percent for females spayed from <6 mo. through 1 year of age ( p <0.05–0.01). The suggested guideline for males, given the risks of joint disorders, is delaying neutering until over 2 years of age. For females, with the same joint issues as males plus the risks of UI, the suggested guideline is delaying spaying until over 2 years of age.
The study population was 318 intact males, 365 neutered males, 190 intact females, and 374 spayed females for a total of 1,247 cases. In intact males and females, the level of occurrence of one or more joint disorders was 5 percent and 4 percent, respectively. Neutering males at <6 mo. and at 6–11 mo. was associated with risks of 25 percent and 11 percent, respectively ( p <0.01). In females, spaying at <6 mo. and at 6–11 mo. was associated with risks of 18 percent and 11 percent ( p <0.01, when combined). The occurrence of one or more of the cancers followed in intact males was a high 15 percent and for intact females 5 percent. Neutering males at <6 mo. and at 6–11 mo. was associated with increased risks of cancers to 19 and 16 percent, respectively ( p <0.01). Spaying females at <6 mo. and at 6–11 mo., was associated with increases in cancers to 11 and 17 percent, respectively ( p <0.05, when combined) and spaying at 1 year and at 2–8 years was associated with increased risks of 14 percent ( p <0.01, when combined). The occurrence of MC in intact females was 1 percent and for those spayed at 2–8 years, 4 percent. For females left intact, 4 percent were reported with PYO. No cases of UI were reported in females spayed at any age. The suggested guideline for males, based on the increased risks of joint disorders and cancers, is delaying neutering until beyond a year of age. The suggested guideline for females, based on the increased occurrence of cancers at all spaying ages, is leaving the female intact or spaying at one year and remaining vigilant for the cancers.
The study population was 90 intact males, 103 neutered males, 69 intact females, and 91 spayed females for a total sample of 353 cases. This is a giant breed where one might expect a high risk of joint disorders. However, both intact males and females have low levels of joint disorders, just 1 and 2 percent, respectively. For both males and females, there was no evident increase in this measure with neutering. The occurrence of one or more of the cancers followed in intact males was 6 percent and for intact females, 3 percent. There was no evident increase in this measure of cancers with neutering in either sex. In intact females, MC was diagnosed in just 2 percent and PYO in 6 percent. In early-spayed females, no UI was reported. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered males or females, those wishing to neuter should decide on the appropriate age. However, given the large body size, and physiology of late musculoskeletal development, neutering well-beyond year 1 should be considered.
The study population was 30 intact males, 19 neutered males, 21 intact females, and 16 spayed females for a total of 86 cases. Even with the small number of cases, this breed was chosen for analyses because of the large body size: challenging the Great Dane for height, and where one might expect an increased risk of joint disorders. In this sample, 7 percent of intact males and none of the intact females had a joint disorder. No joint disorders were seen in neutered males or females. With the intact males and females, the incidences of one or more cancers were 8 percent and 21 percent, respectively. With neutering males at 1 year, there was an increase in cancer occurrence to 25 percent ( p <0.05). There was no evident increase in cancers in neutered females above the relatively high level in intact females. There was no occurrence of MC in intact females or those spayed late. For females left intact, 5 percent were reported with PYO. UI was not reported in any of the spayed or intact females. The suggested guidelines for males given the increased occurrence of cancers around at ages 1–2 years, is neutering beyond 2 years. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered females, those wishing to neuter should decide on the appropriate age. However, given the large body size, and physiology of late musculoskeletal development, some may want to consider neutering females well-beyond year 1.
Jack Russell Terrier
The study population was 92 intact males, 87 neutered males, 84 intact females, and 113 spayed females for a total sample of 376 cases. As in other small dogs, joint disorders were rare; none of the intact males, and just 2 percent of intact females had one or more joint disorders. Neutering was not associated with any increase in this measure in either sex. In intact males, 3 percent, and in intact females none, had one or more of the cancers followed. There was no evident increase in cancer occurrence in either sex with neutering at any age. In females left intact, MC was seen in 1 percent, as was PYO. In those spayed at 2–8 years, MC was diagnosed in 3 percent. UI was not diagnosed in any females. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered males or females, those wishing to neuter should decide on the appropriate age.
The study population was 714 intact males, 381 neutered males, 400 intact females, and 438 spayed females for a total of 1,933 cases. One or more joint disorders were reported in 6 percent of both intact males and intact females. This measure was significantly increased to 13 percent for males neutered before 6 mo. ( p <0.01). In females spayed at <6 mo. and 6–11 mo., the risk of a joint disorder was 11–12 percent for each period ( p <0.01, spay periods combined). The occurrence of cancers followed was 8 percent and 6 percent, respectively, for intact males and females. Neutering at the various ages was not associated with any evident increased risk in the cancers. The occurrence of MC in intact females was 1 percent and for those spayed at 2–8 years, 2 percent. For females left intact, 2 percent were reported with PYO. UI was reported at a low rate (2–3%) in females spayed at various ages though 1 year. Given the significant occurrence of joint disorders in males neutered at <6 mo., the suggested guideline for males is neutering beyond 6 months. For females, given the increased risks of joint disorders with spaying through 11 months of age, the suggested guideline is delaying spaying until beyond a year of age.
The study population was 49 intact males, 72 neutered males, 65 intact females, and 86 spayed females for a total sample of 272 cases. As mentioned in Appendix 1 , the Maltese and Chihuahua vie for the smallest breeds and the Great Dane and Irish Wolfhound for the largest, but all four breeds share a low predisposition to joint disorders. For the Maltese in both sexes, there was no occurrence of joint disorders in either those left intact or neutered. Virtually the same picture emerges with cancers, with only one of 64 intact females being diagnosed with a cancer. There was no occurrence of MC in the intact females and only one case among the 19 females spayed at 2–8 years. PYO was seen in none of the intact females. UI did not occur in any of the females.
Lacking a noticeable occurrence of increased joint disorders or cancers in neutered males or females, those wishing to neuter should decide on the appropriate age.
The study population for this small-dog breed was 47 intact males, 63 neutered males, 25 intact females and 96 spayed females for a total sample of 231 cases. There was virtually no occurrence of any joint disorders in males or females either left intact or neutered. The incidence of cancers in intact males was 4 percent and in females, zero percent. There was no indication of cancer increase related to neutering in either sex. There was no occurrence of MC in any of the females left intact or spayed, and a 4 percent occurrence of PYO in intact females. None of the females was diagnosed with UI. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered males or females, those wishing to neuter should decide on the appropriate age.
The study population was 84 intact males, 69 neutered males, 65 intact females, and 104 spayed females for a total sample of 322 cases. As with other dogs of small body size, both males and females had no occurrences of joint disorders in either those left intact or neutered. With regard to cancers, for both males and females left intact, the occurrence of cancers was zero, and there was no indication of increased cancer risk related to neutering in either sex. There was just one case of MC in females left intact, and 7 percent with PYO. None of the females was diagnosed with UI. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered males or females, those wishing to neuter should decide on the appropriate age.
The study population was 49 intact males, 53 neutered males, 58 intact females, and 78 spayed females for a total sample of 238 cases. While the AKC registers all the Poodle varieties as the same breed, the three main varieties are dealt with separately here because of differences in size. In intact males, 4 percent had one or more joint disorders and in intact females there was no occurrence of a joint disorder. In neutered males and females, there was no evident increased risk of a joint disorder. There was a 2 percent occurrence of cancers in intact males and none in intact females. In neutered males and females, there was no noteworthy occurrence of cancers. In intact females, there was only a single case of MC and no case of PYO in intact females and no occurrence of UI in spayed females. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered males or females, those wishing to neuter should decide on the appropriate age.
The study population was 41 intact males, 60 neutered males, 30 intact females, and 69 spayed females for a total sample of 199 cases. The AKC registers the Toy, Miniature, and Standard Poodle varieties, all as the same breed. However, because of differences in size, the varieties of Poodles are dealt with separately here. There was no occurrence of a joint disorder in intact males or females. However, in males neutered at 6-11 mo., there was a significant 9 percent occurrence of joint disorders ( p <0.01), reflecting CCL. In spayed females, there was no occurrence of a joint disorder. In intact males and females, there was a 5 and zero percent occurrence of cancers, respectively. There was no indication of increased cancer occurrence related to neutering in either sex. The only occurrence of MC in females was one female that had been spayed at 2–8 years. Of intact females, 6 percent developed PYO. Just one female spayed at <6 mo. developed UI. The suggested guideline for males, based on the significant occurrence of a joint disorder with neutering at 6-11 mo., is delaying neutering until a year of age. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered females, those wishing to neuter should decide on the appropriate age.
The study population was 47 intact males, 88 neutered males, 53 intact females, and 87 spayed females for a total sample of 275 cases. The AKC registers the Toy and Miniature, along with the Standard Poodle, as all being Poodles. However, because of differences in size, the varieties of Poodles are dealt with separately here. There was a 2 percent occurrence of joint disorders in both intact males and females. In males neutered at <6 mo., there was a non-significant increase to 8 percent, and in spayed females, there was no occurrence of joint disorders. The occurrences of cancers in intact males and females were 4 and 2 percent, respectively. In males neutered at 1 year of age, the occurrence of one or more cancers rose to a significant 27 percent ( p <0.01), all due to the increased risk of LSA. In females, there was no significant increase in cancers with spaying. There was a 4 percent occurrence of MC, and a 2 percent occurrence of PYO in the females left intact. Just one female spayed beyond 2 years later developed UI. The suggested guideline for males, based on the occurrence of one or more cancers with neutering at 1 year, is to delay neutering until 2 years of age. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered females, those wishing to neuter should decide on the appropriate age.
The study population was 96 intact males, 106 neutered males, 63 intact females, and 118 spayed females for a total sample of 383 cases. In intact males and females, the occurrences of joint disorders were zero and 2 percent, respectively. In neutered males and females, there was no evident increased occurrence of joint disorders. The level of occurrence of one or more cancers in intact males was 6 percent and in intact females, 8 percent. Neutering males and females did not lead to any evident increase in risk of a cancer. There were no cases of MC in females left intact or spayed at any time, and there was a 5 percent occurrence of PYO in the intact females. None of the females was diagnosed with UI. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered males or females, those wishing to neuter should decide on the appropriate age.
The study population was 315 intact males, 152 neutered males, 143 intact females, and 239 spayed females for a total sample of 854 cases. Joint disorders are a major concern in this breed with 8 percent of intact males and 16 percent of intact females having one or more joint disorders. In males, neutering at <6 mo. and at 6-11 mo. resulted in 10 percent and 22 percent occurrences (combined p <0.05). In females, spaying at <6 mo. resulted in a significant 43 percent occurrence ( p <0.05), the main joint disorder being CCL. The cancers followed occurred in the intact males and females at 16 and 11 percent, respectively. These relatively high occurrences of cancers in intact males and females were not increased by neutering at any age. Of females left intact or spayed at 2–8 years, 8 and 5 percent were diagnosed with MC, respectively. In intact females, 12 percent were diagnosed with PYO. With regard to UI, 1 percent of intact females had UI, and in females spayed at <6 mo. and 6-11 mo., 4 and 6 percent, respectively had UI. The suggested guideline for males, given the risk of joint disorders for those neutered at 6-11 mo. or earlier, is neutering beyond a year of age. For females, given the increased risk of joint disorders with neutering at <6 mo., the suggested guideline is spaying beyond 6 months.
The study population was 26 intact males, 27 neutered males, 18 intact females, and 23 spayed females for a total sample of 94 cases. This breed was chosen because of the large size. In intact males and females, the occurrences of one or more joint disorders were 8 percent and 6 percent, respectively. While there was no evident increase in joint disorders with neutering males, in females spayed at <6 mo., joint disorders increased to a significant 100 percent ( p <0.01). The cancers followed occurred in intact males and females at 4 and 11 percent, respectively. With neutering males and females, there were no noteworthy increases in cancers. There was no occurrence of MC in either the intact or spayed females. In intact females, PYO was diagnosed in 15 percent There was no occurrence of UI in spayed females. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered males those wishing to neuter should decide on the appropriate age. The suggested guideline for females given in the increased risk of joint disorders with neutering at <6 mo., is neutering beyond 6 months. However, given the large body size, some may wish to consider neutering well-beyond 1 year of age.
The study population was 31 intact males, 30 neutered males, 20 intact females, and 52 spayed females for a total sample of 133 cases. There were no joint disorders in intact males and just one in the intact females. In neutered males, the only joint disorder was in one of the males neutered at <6 mo. and in females there was no joint disorder associated with spaying. The occurrence of cancers in intact males was 6 percent and in intact females, zero. There were no evident increases in cancers in neutered males or females. There was no occurrence of MC in intact or spayed females and a 14 percent occurrence of PYO in intact females. Spaying at 6-11 mo. resulted in a 6 percent occurrence of UI, but at 1 year a 33 percent occurrence. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered males, those wishing to neuter should decide on the appropriate age. However, to avoid the high level of UI occurrence in females, one could consider spaying females at, or beyond, 2 years.
The study population was 104 intact males, 112 neutered males, 77 intact females, and 139 spayed females for a total sample of 432 cases. In this small-dog breed there were no occurrences of joint disorders in either intact or neutered males and females, revealing virtually no vulnerability in this regard. There was no occurrence of the cancers followed in intact males and females. In neutered males there was no occurrence of cancers. However, in females, the occurrence of cancers for those spayed at 6-11 mo. was 7 percent and at 1 year this measure reached a significant 18 percent ( p <0.01). MC occurred in 3 percent of intact females. PYO occurred in 5 percent of intact females. UI was not reported in any females. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered males, those wishing to neuter should decide on the appropriate age. The picture is very different for spaying females where the increased risk of cancers started with spaying at 6-11 mo., reaching 18 percent with spaying at year 1. The suggested guideline for females is to delay spaying until the female is 2 years of age. Another possibility is to spay a female a month or two before 6 months to avoid the increased risk of cancers.
West Highland White Terrier
The study population was 35 intact males, 33 neutered males, 28 intact females, and 46 spayed females for a total sample of 142 cases. Just one intact male had a joint disorder, and other than this, no joint disorders were reported in intact females or in neutered males or females. None of the intact males or females had any of the cancers followed. There were no noteworthy occurrences of the cancers in neutered males or females. There were no occurrences of MC in either intact or neutered females, and a 7 percent occurrence of PYO in intact females. The occurrence of UI was 14 percent for females spayed at <6 mo. and 6 percent at 6-11 mo. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered males or females, those wishing to neuter should decide on the appropriate age. However, for females, one could consider delaying spaying until a year of age to avoid the risk of UI.
The study population was 134 intact males, 178 neutered males, 144 intact females, and 229 spayed females for a total sample of 685 cases. There were no joint disorders reported in intact males, and in intact females, just 1 percent. In neutered males and females there were no noteworthy occurrences of joint disorders. In intact males and intact females, just 1 percent were reported with at least one of the cancers followed. In both neutered males and females, none of the cancer occurrences was noteworthy. In intact females, the occurrence of MC was 1 percent as was the occurrence with spaying at 2–8 years. PYO was reported in 7 percent of intact females. No UI was reported in any of the intact or spayed females. Lacking a noticeable occurrence of increased joint disorders or cancers in neutered males or females, those wishing to neuter should decide on the appropriate age.
Since the reporting from this center of increased risks of joint disorders and some cancers in Golden Retrievers, Labrador Retrievers, and German Shepherd Dogs ( 11 – 13 ), the appropriate age of neutering has become a common point of discussion ( 16 – 18 ). With the evidence-based information on the risks, if any, of joint disorders, cancers, PYO and UI associated with neutering at different ages for males and females of various as dog breeds, dog owners, and their veterinarians, can use this information to select an age for neutering for the long-term health of their companion dogs on a case-by-case basis.
The overall major finding from the present study is that there are breed differences – and sometimes sex differences – with regard to the increased risks of joint disorders and cancers associated with neutering at various ages. For example, with the Boston Terrier, neutering females at the standard 6 month age did not increase the risks of joint disorders or cancers over that of dogs left intact, but with males, neutering before a year of age was associated with a significant increase in cancers. The opposite effect with genders was seen in the Cocker Spaniel where neutering at 6 months was not associated with an increase in joint disorders or cancers in males, but in females there was a significant increase in risk of cancers to 17 percent with neutering before 2 years.
Another important finding that holds across several breeds is that with the small-dog breeds – Cavalier King Charles Spaniel, Chihuahua, Corgi, Dachshund, Maltese, Pomeranian, Poodle-Toy, Pug, Shih Tzu, Yorkshire Terrier –the occurrences of joint disorders were close to zero in both the intact and neutered males and females. In these small-dog breeds, the occurrence of cancers was low in both those kept intact and neutered. Two exceptions were the Boston Terrier and Shih Tzu where there was there a significant increase in cancers with neutering.
As noted in the results section, the mean date of last entry per patient in the hospital record ranged from about 4.5 to 5.5 years, which means the data especially represent rather early-occurring joint disorders and cancers. The perspective taken here is that it is the early occurring joint disorders and cancers that are the most impactful on the human caregivers, both emotionally and financially, as well as their dogs. To just delay neutering by a year or so to lower the risk of a joint disorder or cancer in those breeds where the issue is relevant, is a noteworthy goal, making it worthwhile to discuss appropriate ages to neuter with caregivers who have a new puppy.
A suggested guideline for the use of the data presented here for those who may wish to focus on a breed or two, is to first scroll through Table 1 to peruse the breeds for a brief look at the neutering guidelines for the breeds of interest. The next step could be to refer to summary paragraphs in the Results section, which present the major findings with a suggested guideline for neutering age. Then for a third step, one could turn to Appendix 1 for detailed joint disorder and cancer tabular data as well as data on MC, PYO, and UI. Our intention is to offer readers data-based information to make case-by-case decisions about age of neutering. As is clearly evident in the breed-specific data presented, one cannot make a generalization for all dogs about age of neutering guidelines.
As mentioned, this study involved 35 breeds, counting the three varieties of Poodles as three breeds. Thus, most breeds registered by AKC or other comparable agencies were not covered. The breeds chosen were the most popular, and with the largest dataset in our records, or were included to sample the largest range of breed sizes as was feasible. Hence, some of the largest breeds (e.g., Great Dane, Irish Wolfhound) and smallest breeds (Miniature Schnauzer, West Highland White Terrier) were included despite lower numbers of patient records. While with some of the most popular breeds there were over 1,000 cases in the database, most breeds ended up with 200 to 500 cases which was sufficient for statistical analyses where the impact of neutering was substantial.
A suggestion for those interested in a breed not covered in this study is to find a breed or two closest genetically to the breed of their interest in order to get an estimate of the various disease risks, if any, associated with neutering. However, one needs to bear in mind that even genetically related breeds may vary a great deal. An example is seen when comparing Golden and Labrador Retrievers, using the data from this study, where in the Labrador, there was no increase in cancer risk above that of intact dogs with neutering, but in the female Golden, the risk of a cancer with neutering increased to 2–4 times that of the 5 percent level of intact females. The popular Poodle breed provides another example, where there are three major varieties in size, the Standard, Miniature, and Toy. In the Standard, neutering males at 1 year was associated with a highly significant increase in the risk of a cancer (mainly LSA) to over six times that of intact males, whereas in the Miniature, there was no increase in cancers with neutering but a significant increase in joint disorders (mainly CCL) with neutering at 6-11 mo.
A likely mechanism by which early neutering may lead to a joint disorder is related to disturbance of the closure of the long-bone growth plates by gonadal hormone secretion as the animal approaches maturity ( 19 , 20 ). We have proposed that neutering much before the closure of growth plates allows the long bones to grow a little longer than normal, and may sufficiently disturb joint alignments in some neutered dogs to lead to a clinically-apparent joint disorder.
Given the frequency with which early neutering is performed in dogs, it seems surprising that osteoporosis has not been examined given that in humans, chronic loss of gonadal hormones is associated with osteoporosis ( 21 ). It could be that the wolf ancestor of the dog had one breeding season and that the bone structure of mature dogs was not as affected by seasonal fluctuations of gonadal hormones as with a permanent gonadal hormonal loss in humans.
One of the frequently mentioned advantages of early neutering of female dogs is protection against MC ( 22 ). There may be important genetic, breed-line differences in the occurrence of MC that are not portrayed in our database. However, relevant to the discussion of MC is the recent meta-analysis of published studies on neutering females and MC, finding that the evidence linking neutering to a reduced risk of MC is weak ( 23 ). In the data gathered in this study, through 11 years of age, the occurrence of MC in females left intact was rarely above 6 percent and frequently 2 percent or less. For those neutered at <6 months, there was, as expected, no occurrence of MC. Obviously with most cases of intact females not followed through 11 years, and with the 12-year cut-off for those that were followed, many occurrences of MC were missed. However, it seems reasonable, that if MC was a common occurrence in intact females that this disease would have been more frequent in the intact females followed. Further, a very late onset of MC would seem less disturbing to pet owners than the much earlier onsets of joint diseases and other cancers.
For males, there is some concern that neutering beyond puberty will increase the likelihood of a problem behavior such as aggression. However, studies show that while neutering males can reduce aggression to people or other dogs in about 25 percent of males, neutering prior to puberty is no more effective in preventing this problem than is neutering in adulthood in resolving the problem ( 24 , 25 ).
This paper deals primarily with the risks of diseases that are seen within a given breed and sex. Comparisons between breeds are difficult to interpret, in part because of differences in developmental and physiological factors between breeds including those between smaller and larger breeds. In the text we have reported the occurrences of various diseases in percentages but in statistical analyses the actual data are used. When disease incidence is particularly low in one or more neutering subgroups, the ability to detect significant differences will be low, but there still could be differences which may or may not have been evident in the statistical analyses.
There are at least two major limitations to this study. First, relatively few breeds are covered compared to those included in the various breed registries of kennel clubs and canine organizations. This limitation was necessary so as to apply the same diagnostic criteria for diseases covered across all breeds, using the same database, and the necessity of having sufficient cases for analyses. Second, no information is available as to the reasons the owners or others chose to neuter, or not to neuter their dogs. In California, the vast majority of dogs are neutered, and since 2005 it is legally required for dogs to be neutered prior to adoption from an animal shelter or humane society ( 26 ); many breeders impose the same requirement.
In conclusion, the data presented should provide to veterinarians and interested puppy caregivers data-based information for the best age for neutering to avoid increasing the risk of joint disorders and some cancers beyond that of leaving the dog intact. Readers can note that an elevated risk for a joint disorder or cancer occurs in relatively few of these breeds. In other words, with most breeds or sexes, neutering can apparently be done without referral to a particular age, at least with regard to the joint disorders or cancers covered in this study. Of course, individual factors must be taken into account. For puppies of mixed breed, another paper that is currently in press provides data-based information dealing with age of neutering and the risk of one or more joint disorders as a function of the dog adult weight category ( 27 ). This information can also help inform decisions on age of recommended neuter in purebred dogs where the breed is not covered in our data.
Data Availability Statement
The datasets presented in this study can be found in online repositories. The names of the repository/repositories and accession number(s) can be found below: (Figshare, doi: 10.6084/m9.figshare.7231010 ).
BH, LH, and AT: conceived and designed study, collected and complied, and analyzed data. NW: statistical analyses. BH, LH, AT, and NW: drafted and edited manuscript. All authors contributed to the article and approved the submitted version.
Supported by the Canine Health Foundation (#01488-A), the Center for Companion Animal Health, University of California, Davis (# 2009-54-F/M), and Versatility in Poodles.
Conflict of Interest
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
We wish to acknowledge the assistance of the following individuals in collecting the data: Siobhan Aamoth, Cristina Bustamante, Valerie Caceres, Rhoda Coscetti, Madeline Courville, Elvira Covarrubias, Aaron Frankel, Matthis Grupe, Vanessa Hsieh, Mi Hwangbo, Katrina Larkin, Arielle Merlos, Emily Parker, Roger Pender, Venus Pun, Emily Romanko, Sara Sewell, Sandra Walther, and Lexy Wetzel.
The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fvets.2020.00388/full#supplementary-material
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Keywords: elbow dysplasia, hip dysplasia, cranial cruciate tear, lymphoma, mast cell tumor, hemangiosarcoma, osteosarcoma
Citation: Hart BL, Hart LA, Thigpen AP and Willits NH (2020) Assisting Decision-Making on Age of Neutering for 35 Breeds of Dogs: Associated Joint Disorders, Cancers, and Urinary Incontinence. Front. Vet. Sci. 7:388. doi: 10.3389/fvets.2020.00388
Received: 02 April 2020; Accepted: 01 June 2020; Published: 07 July 2020.
Copyright © 2020 Hart, Hart, Thigpen and Willits. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) . The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Benjamin L. Hart, email@example.com
This article is part of the Research Topic
Effective Options Regarding Spay or Neuter of Dogs
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Genomics of Dog Domestication and Breed Formation
Click the image to download
Click here for an interactive look at the relationships between individual breeds (created by Nick Evershed at the Guardian, Australia)
The transition from their wild wolf-like ancestors to modern domestic dogs ushered in profound changes in the canine genome, reflected in changes in behavior, morphology, metabolism, and other biological phenomena. Since dogs have been living and working with humans for more than 15,000 years, selective breeding has created an array of dog breeds with diverse characteristics seen today. The Ostrander lab seeks to understand the effects that rapid and strong artificial selection has had on the modern dog genome. Using hundreds of whole genome sequences and tens of millions of informative SNPs from a comprehensive sampling across a diversity of modern breed dogs, free-breeding populations, and other species of canids, we are working to identify the genomic variants that coincide with alterations in basic biology. Our own interests focus on growth and cell cycle regulation and breed development.
Our latest study includes 1355 dogs from 161 diverse breeds as well as breed varieties and populations from around the world. Using a HighDensity array of 150,000 SNPs we assessed the relationships between the breeds using both distance, as shown on the tree above, and haplotype sharing ( Parker et al. 2017 ). We identified 23 clades of related breeds as well as more than 150 instances of cross-breeding that went into the development of individual breeds. The majority of breed development could be calculated from genome data as having taken place within the last 200 years, supporting the idea that modern breeds were refined to current standards starting in the 1800's.
To further expand our understanding of breed development and relationships we continue to add more breeds. We are especially interested in breeds that are not often found outside their country of origin, in order to fill in the missing links between common breeds. We have recently released a paper describing a large number of breeds native to Italy ( Dreger et al. 2018 ) that illuminates the different methods used to develop a new breed.
When exploring dogs as a model for understanding morphological characteristics, behavior, or heritable disease, it is foundational to understand how dogs became the companions we know today. Both the transition from wolf to proto-dog, as well as the nature of dogs and their relationship to man early in their history is essential to this understanding. To this end, we are creating whole genome sequences for multiple ancient dogs from North America, ranging in age from 800 to 11,000 years old. Using techniques pioneered to build the Neanderthal genome, we are using these data to understand the evolution of the modern dog from its primitive ancestors, and how their genomes changed over time as they became increasingly and inextricably intertwined in our lives.
For information about the Dog Genome Project publications concerning the genomics of dog breeds, please view the associated publications from the Genomics of Dog Breeds Study .
We are seeking samples from dogs from all recognized breeds. We are currently interested in obtaining more samples from rare breeds and breeds that are common only in their country of origin. To donate a sample for this study, please E-mail the Samples Manager at [email protected] .
Dogs in Research
“clearly, some testing and research is done in dogs for historical reasons [existence of benchmark data] rather than because they are the best models.”.
JOANNE ZURLO ET AL, “CRITICAL EVALUATION OF THE USE OF DOGS IN BIOMEDICAL RESEARCH AND TESTING,” ALTEX, APRIL 2011
Although the number of dogs used in research has declined by 72% since their peak use in 1979, the most current USDA statistics show that 58,511 dogs were used for “research, testing, teaching, or experimentation” in 2019, although the exact purposes for which these dogs were used remain unclear.
The majority of dogs used in research, upwards of 75%, are estimated to be used in pharmaceutical testing, even though many scientists have concluded that they are poor predictors of drug effects in the human body. They are still used because regulatory authorities require that drugs be tested in both a rodent and a non-rodent species for toxicity, and the latter is often dogs, due to their ready availability, as well as their trusting and social nature, which makes them easy to handle. Dogs are also used in many other areas of biomedical research, including heart research, surgery, dental health and studies of hereditary diseases, in addition to research on the health, nutrition and behavior of dogs themselves.
Of all dogs used in research, beagles are the breed most often used in research because of their intermediate size and loving nature. Kevin J. Stafford, author of The Welfare of Dogs, speculated that “Their existence for some time as ‘the’ laboratory dog may make it easier for handlers and research scientists to use them without becoming too emotionally attached to them.” When experiments call for larger animals, hounds (mongrels) are commonly used. Although the U.S. does not collect information on the breeds of dogs used in research, data obtained from Freedom of Information Act requests filed by NAVS revealed that many other breeds, including, but not limited to, Golden Retrievers, Labrador Retrievers, Greyhounds, Pit Bulls and Schnauzers, are among the dogs used in research as well.
Most dogs used in research are purchased from Class A dealers, licensed commercial breeders that sell “purpose-bred” dogs specifically for research. They breed beagles, hounds and mongrel dogs and raise the animals on their own premises to fulfill orders for canines ranging from 33-60 pounds that are 6 to 12 months old. Most dogs sold for research are less than a year old. From a research perspective, dogs from Class A dealers have good health and good veterinary care (known vaccination history, preventative treatment for parasites, known pedigree and improved socialization), but they are expensive, costing over $700 per dog, based on the most current price list from top vendors Ridglan Farms, Inc. and Marshall Bioresources.
These vendors offer devocalization services (a surgical procedure which makes it physically impossible for the dog to bark) for $20-$47 per dog; this is performed so that barking dogs do not disturb lab technicians. There are current state legislative initiatives to ban devocalization, as the surgery can cause serious health issues, including infection, and increases the possibility of food and water becoming trapped in dogs’ lungs. As a result, it is currently illegal in five states.
Some research institutions purchase dogs from Class B dealers , licensed dealers that sell “random source” dogs. These are dogs that are obtained from an animal shelter or dog pound (a practice known as “pound seizure”), at auction, or from any person who did not breed and raise the dogs on their premises. Class B dogs are less expensive than “purpose-bred” dogs used in research, although research with these animals may be compromised because of their unverifiable health status, poorly-defined temperament and unknown age.
Over the past several years, more research institutions have moved away from using Class B dogs, and as a result, the number of Class B dealers has declined. In December 2013, the National Institutes of Health (NIH) announced that they would implement a new policy prohibiting the procurement of dogs from Class B dealers using NIH grant funds starting in Fiscal Year 2015. This prohibition went into effect on October 1, 2014. Dogs used in research supported by the NIH now need to be acquired from USDA Class A dealers or other approved legal sources such as privately owned colonies or client owned animals. It is important to note, however, that dogs with Class B-like characteristics, namely large, mature, socialized out-bred hounds or mongrels, are being bred by Class A dealers for use in scientific experimentation.
Once in the laboratory, dogs older than four months of age are identified with a tag or may have an ID number tattooed in their ear. They are housed in spaces depending on their weight, according to recommendations made by The Guide for the Care and Use of Laboratory Animals. It is recommended that dogs less than 33 pounds have a minimum floor area of eight square feet per animal; dogs up to 66 pounds have a minimum floor area of 12 square feet per animal; and dogs more than 60 pounds have a minimum floor area of 24 square feet per animal. The Guide also recommends that cage height be sufficient for the animals to be comfortable standing with their feet on the floor.
Dogs used in research in laboratory settings have been shown to display signs of stress, fear and anxiety. A number of common laboratory procedures can cause this response, including cage changing, the removal of a dog from a stable social group, changing of established maintenance routines, or restraint or confinement in a strange setting. While some dogs are able to adapt positively to stressors, other dogs are unsuccessful and can develop disorders and dysfunctions that can adversely affect their quality of life, in addition to significantly impacting the research in which the animal is involved.
Laboratory dogs that are exhibiting signs of short term stress may shake, crouch, display signs of restlessness or oral behaviors (tongue out, licking muzzle, swallowing). Dogs that display signs of long term or chronic stress may be vocal, exhibit repetitive behaviors, have low posture, increase autogrooming and eat feces. It has been noted that dogs often stop such behaviors when their handlers enter the room, resulting in a serious underestimation of the true mental and physical condition of dogs used in research in laboratory settings.
Man’s best friend deserves better than this. Considering that the differences between dogs and humans make them a poor model for humans, there is no reason to continue subjecting these amazing companion animals to unnecessary pain and experimentation.
Field, G. and Jackson, T.A. (2007). The Laboratory Canine . CRC Press. Hasiwa, N., et al. (2011) Critical Evaluation of the Use of Dogs in Biomedical Research and Testing in Europe. ALTEX . Vol. 28, 4/11, p. 326-340
Meunier, L.D. (2006). Selection, Acclimation, Training, and Preparation of Dogs for the Research Setting, ILAR Journal. Vol 47, Number 4, p. 326-347.
National Research Council. (2009). Scientific and Humane Issues in the Use of Random Source Dogs and Cats in Research Stafford, K.J. (2006). The Welfare of Dogs .
Turner, M. (2011). Call to curb lab tests on dogs. Nature . 474, p. 551.
When Should You Neuter Your Dog to Avoid Health Risks?
Comprehensive study lays out guidelines for 35 dog breeds.
- by Amy Quinton
- July 15, 2020
Some dog breeds have higher risk of developing certain cancers and joint disorders if neutered or spayed within their first year of life. Until now, studies had only assessed that risk in a few breeds. A new, 10-year study by researchers at the University of California, Davis, examined 35 dog breeds and found vulnerability from neutering varies greatly depending on the breed. The study was published in the journal Frontiers in Veterinary Science.
“There is a huge disparity among different breeds,” said lead author Benjamin Hart, distinguished professor emeritus at the UC Davis School of Veterinary Medicine. Hart said there is no “one size fits all” when it comes to health risks and the age at which a dog is neutered. “Some breeds developed problems, others didn’t. Some may have developed joint disorders but not cancer or the other way around.”
Researchers analyzed 15 years of data from thousands of dogs examined each year at the UC Davis Veterinary Medical Teaching Hospital to try to understand whether neutering, the age of neutering, or differences in sex when neutered affect certain cancers and joint disorders across breeds. The joint disorders examined include hip dysplasia, cranial cruciate ligament tears and elbow dysplasia. Cancers examined include lymphoma; hemangiosarcoma, or cancer of the blood vessel walls; mast cell tumors; and osteosarcoma, or bone cancer.
In most breeds examined, the risk of developing problems was not affected by age of neutering.
Breed differences by size and sex
Researchers found that vulnerability to joint disorders was related to body size.
“The smaller breeds don’t have these problems, while a majority of the larger breeds tend to have joint disorders,” said co-author Lynette Hart, professor at the UC Davis School of Veterinary Medicine.
One of the surprising exceptions to this was among the two giant breeds — great Danes and Irish wolfhounds — which showed no increased risk to joint disorders when neutered at any age.
Researchers also found the occurrence of cancers in smaller dogs was low, whether neutered or kept intact. In two breeds of smaller dogs, the Boston terrier and the shih tzu, there was a significant increase in cancers with neutering.
Another important finding was that the sex of the dog sometimes made a difference in health risks when neutered. Female Boston terriers neutered at the standard six months of age, for example, had no increased risk of joint disorders or cancers compared with intact dogs, but male Boston terriers neutered before a year of age had significantly increased risks.
Previous studies have found that neutering or spaying female golden retrievers at any age increases the risk of one or more of the cancers from 5 percent to up to 15 percent.
Discuss choices with veterinarians
Dog owners in the United States are overwhelmingly choosing to neuter their dogs, in large part to prevent pet overpopulation, euthanasia or reduce shelter intake. In the U.S., surgical neutering is usually carried out by six months of age.
This study suggests that dog owners should carefully consider when and if they should have their dog neutered.
“We think it’s the decision of the pet owner, in consultation with their veterinarian, not society’s expectations that should dictate when to neuter,” said Benjamin Hart. “This is a paradigm shift for the most commonly performed operation in veterinary practice.”
The study lays out guidelines for pet owners and veterinarians for each of 35 breeds to assist in making a neutering decision. Read the full list here.
Other authors include Abigail Thigpen with UC Davis School of Veterinary Medicine, and Neil Willits with the Department of Statistics in the UC Davis College of Letters and Science. Research support came from the Canine Health Foundation, the UC Davis Center for Companion Animal Health and Versatility in Poodles.
Benjamin Hart, School of Veterinary Medicine, [email protected]
Lynette Hart, School of Veterinary Medicine, [email protected]
Amy Quinton, News and Media Relations, 530-752-9843, [email protected]
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Have your heart set on a breed? Here’s why it’s important to consider different types of dogs
Think you need a small dog here's why you should research different types of dogs first.
Perhaps you love your friend’s Yorkie . Maybe you grew up with a beagle and always dreamt of having one of your own. Getting fixated on a specific breed is normal and natural, and there’s no shame in it. Just like gender disappointment is a “thing” in parenting, so is dreaming about welcoming a specific dog with a distinct look and characteristics into your family.
Why you should research different types of dogs
Resources to research breeds.
Still, you want to consider different types of dogs while searching for a new furry family member. It may be difficult to wrap your head around, but researching other breeds and considering all of your options is an essential step in the process of choosing a dog breed. That doesn’t mean you must consider all dog breeds — that’s overwhelming — but you want to look into several. Here’s why and how to jumpstart your search for your next four-legged best friend.
The process of choosing a pet can be fun but overwhelming. It’s tempting to want to jump for the breed you think you love most. However, you want to take a beat and do your homework. Here’s why.
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The breed you love may not be a good fit for your lifestyle
You may think that a small dog is perfect for your small apartment. However, not all smaller breeds are great apartment dogs. Some, like Jack Russell terriers and miniature American shepherds, need tons of physical activity. Often — but not always — these pets do best in a home with a backyard.
Other breeds, such as Chihuahuas , are prone to separation anxiety and have tinier bladders. They need frequent walks or chances to go to the potty. If you work double shifts, these pups may not be best for you.
On the other hand, if you’re around a bunch and looking for an exercise buddy, a Lab may be a great jogging companion. French bulldogs, which have flat faces and are prone to breathing issues, likely won’t be running any 5Ks by your side (but they will be thrilled to cuddle after you cross the finish line).
Some dogs are also better with other pets and small children than others, and this is an important factor to consider.
The shelter may not have the dog you want
Adopting a dog from a local shelter is one of the most rewarding things you can do. You give one pet a second chance and another animal the opportunity to take their space without euthanization.
Shelters have tons of unique pets, including purebreds and mutts. They may not have the breed you thought you wanted, though. You have a few options in this case. If you feel you’ve really done your homework, you can look into reputable breeders or breed-specific rescues. You can also wait and ask a shelter to contact you if it gets the breed you’re looking to adopt.
Alternatively, you can have meet-and-greets with other pets. One may surprise you, and it could be the beginning of a decades-long friendship.
You simply fall in love with another dog
You’re not tied to a specific breed. If you went to a shelter thinking you wanted a small breed but fell in love with the gigantic lovable pit bull that thinks they’re a lap dog, don’t limit yourself. If you love the dog and can meet their physical and mental stimulation needs, go for it!
We may have just given you homework — sorry. The good news is: You have plenty of resources to look into all types of dogs. Better news: Many allow you to look at and play with cute pups. Some resources include:
- The American Kennel Club (AKC) website. The AKC has tons of information on dog breeds, including personalities, sizes, life spans, and social and physical characteristics.
- Friends and family. Ask your friends and family about dogs they love and which breeds they envision you loving. Sometimes, those who love us best know us best.
- Meet-and-greets. Go down to the shelter with an open mind and meet and greet other dogs. You can also volunteer to walk them. There’s no pressure to adopt one, but it may help you figure out which breeds you connect with most.
- Reputable breeders. While adopting is a great option, reputable breeders have a wealth of knowledge and passion for specific breeds. They want what’s best for the breed and can give you insights into specific characteristics of a type of dog you’re interested in adopting or purchasing from a responsible breeder.
The pet search process can be overwhelming but should be fun. Don’t limit yourself to a specific breed — at least not at first. Research a bunch so you get a feel for the types of dogs out there. Having an open mind can help, especially if your small apartment has weight limits or the local shelter doesn’t have golden retriever puppies (but does have the world’s sweetest German shepherd).
Browsing the AKC website, speaking with family and reputable breeders, and meeting with dogs can help you, too. Remember, all dog breeds have pros and cons, and each pet is unique. What’s most important is that you find the perfect fit for your home and lifestyle so you and your pet can be forever friends.
- 6 affectionate and cute dog breeds for owners who love to cuddle
- 5 safe and fun adventures you can plan with your small dog
- Think big dogs breeds can’t be in an apartment? Think again
- This adorable video of a cat and dog’s friendship is the cutest thing we’ve seen
- How long after neutering a dog does behavior change? These are the differences you might see
- Getting Started
Valentine’s Day celebrates love. Whether you’re single or with someone special, let’s share a secret between friends: Your dog is your main squeeze. Your pooch’s unconditional love and snuggles have helped you get through challenging times, and their one-of-a-kind personality has improved your brightest days.
Showering your dog with love on Valentine’s Day is a no-brainer. However, what should you do for the dog that has given you everything and so much more? Even these days — where news of shortages dominates the headlines — there are so many dog Valentine’s Day activities you and your furry best friend can enjoy this year. Choose one, or consider ditching work and treating your pup to a day of dog pampering and memories.
While everyone else is getting riled up for the biggest football game of the year, animal lovers like us will be tuning into the 19th annual Puppy Bowl on Animal Planet. Team Ruff and Team Fluff will be kicking off an afternoon of adorable fun, and you won't want to miss it. Here's the good news: You don't have to pick between watching the Puppy Bowl or the Super Bowl, either! We'll let you know when and where to tune in for this "aww-inspiring" event, so don't forget to mark your calendars. This is everything you need to know about Puppy Bowl XIX.
When and where to watch Puppy Bowl XIX -- Animal Planet, streaming, and more This year's Puppy Bowl will air on Sunday, February 12 (aka Super Bowl Sunday). Before you get too worried about making time for both big games; rest assured, you can make time for both. The Puppy Bowl will first air on Animal Planet at 2 p.m. ET/11 a.m. PT, according to Discovery. Later in the day, the Super Bowl's kickoff is scheduled for 6:30 p.m. ET/3:30 p.m. PT (via NFL).
As football fans from across the country gear up for Super Bowl Sunday, you might find yourself getting swept up in the hype. We get it! The NFL championship game is a big deal, and it's fun to get together with loved ones to mark the occasion. While you're planning your football-themed menu and decor, we encourage you to consider inviting furry friends, too. At the very least, make sure your own dog is well prepared for a fun day, too. 2023 pet trends revealed that more and more owners treat their dogs like their children, so we wouldn't be surprised to see a rise in dog-friendly Super Bowl parties this year. That's why we've compiled six important ways anyone can accommodate pets at their Super Bowl party -- from finding the right snacks to finding the right space.
Don't forget to provide snacks for dogs, as well as people There are two key components to a successful Super Bowl party -- watching the game and enjoying the food -- so once you've got your location decided, make sure to plan a menu that accommodates everyone you've invited. That means feeding the dogs, too! Most owners will have their own plan for feeding their pup dinner, but when it comes to snacks, it doesn't hurt to be prepared. When in doubt, ask ahead about your canine guests' preferences and restrictions. That way, other pet parents can bring food for their pups -- and no one is excluded. A classic homemade dog biscuit is always a safe snack to have on hand, and they last for a long time as leftovers, too. Since most recipes will have you making and baking dough, you can use a football-shaped cookie cutter or silicone mold to add to the day's festivities!
What Breed of Dog is That? Dog Breed Identification
How to Find Out What Kind of Dog You Have
While many people like to know “what kind of dog is that?” just to satisfy their curiosity, dog breed designations have also been used in an attempt to predict future behavior, match pets to families, find lost dogs, and even to restrict the ownership of certain types of dogs.
Dogs come in all shapes and sizes, and frequently without pedigrees to describe their breed or heritage. The identities of dogs with unknown or mixed-breed lineages are frequently guessed based on their physical appearance, but it is not known how accurate these canine visual breed assessments are.
Faculty and students from the Shelter Medicine Program at the University of Florida College of Veterinary Medicine conducted a national survey of dog experts to compare their best guesses for the breeds of dogs in a series of photographs. These visual assessments were compared to DNA breed profiles for the dogs.
Dog Breed Identification Photo Survey and Results
More than 5,000 dog experts, including breeders, trainers, groomers, veterinarians, shelter staff, rescuers, and others completed the survey. You are invited to view pictures of the 100 dogs in our study, their actual DNA breed results, and what our survey participants guessed their breeds were. Maybe you’ll see a photo that looks like your own special pup!
- Dog breed identification chart
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This study was conducted by Dr. Julie Levy with the assistance of Merial Veterinary Scholar Kathleen Croy and is made possible by a grant from the National Canine Research Council.
You can help our team save more homeless dogs and cats by supporting groundbreaking research and crucial training for students and shelter veterinarians. Please donate today!
The Smartest Dog Breeds Were Pitted Against Each Other. One Came Out on Top
How quick-witted is your canine? Scientists at the University of Helsinki in Finland might have an answer.
In a study published in the journal Nature Scientific Reports , Saara Junttila and colleagues put 1,002 dogs through a series of intelligence tests to assess the performance of 13 different dog breeds.
The series of ten tests, known as smartDOG, were developed by one of the study's co-authors, Katriina Tiira, to examine exploratory behavior, impulsivity, social cognition, spatial problem-solving, logical reasoning and short-term memory.
"We expected that breeds would differ from each other in most traits, and they did," Tiira told Newsweek . "This was well visible for testers doing the smartDOG testing in practice—breeds had typical cognitive profiles in the test."
Junttila said that this was not the case for all traits studied.
"It was a bit surprising that memory and logical reasoning were not affected by breed," she told Newsweek . "It might be that these traits have not been selected for in different breeds, or that environmental effects—such as training history, test situation and previous lifetime experiences—may influence these traits more strongly than breed."
One of the best performing breeds across the test series was the border collie . This is consistent with previous research by Stanley Coren, author of The Intelligence of Dogs and professor emeritus at the University of British Columbia's Department of Psychology.
"According to my research the seven dog breeds with the highest working and obedience intelligence, starting with the brightest are: border collie, poodle, German shepherd, golden retriever, Doberman pinscher, Shetland sheepdog and Labrador retriever," Coren told Newsweek .
In the present study, Labrador retrievers scored near the bottom in the tests involving problem-solving and inhibitory control. However, Coren said that this does not mean the Labrador is unintelligent.
" All of the dog breeds selected for this study are very bright ," he said. In other words, taking these results to mean that the Labrador is the dumbest dog breed is misleading.
"This is equivalent to taking a sample of ten Nobel Prize winners and comparing their intelligence and concluding that because, for example, Marie Curie comes out at the bottom of the list that she must be really dumb," said Coren.
The study, however, did not aim to rank different dog breeds .
"The purpose of the study was really to understand how dog breeds differ from each other in each of the studied traits," Junttila said.
There was, however, one major limitation to the research.
"We did not have access to information on the training histories of the participating dogs, although a large proportion of them very likely were active in dog sports or competitions," Junttila said. "Previous studies have shown that participation in dog sports or the amount of training a dog has received may affect the results of some of these tests, but there is also evidence that many of these traits are heritable. In future studies, we will be investigating the combined effects of breed and training history."
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Tiira said that trainability does not equate to intelligence, although it is unclear how this would affect the test results.
"A dog which is easy to train has a high motivation to work with the trainer/owner," she said. "A highly trainable dog is usually focused on the trainer and motivated to do tricks over and over again, as well as to learn new tricks. Thus, trainability may not have much to do with intelligence, but instead with how easy it is for the trainer to motivate the dog to do several kinds of tasks."
Coren said that a dog's performance in these tests is also dependent on the animal's personality, not just its IQ.
"A simplistic example would be that a dog who is very hyperactive might dash around and miss important clues that might help solve the problem," Coren said. "It is also the case that the sociability of a dog will determine whether or not it pays enough attention to humans to be able to pick up the nuances of commands."
The suggestion that there is some heritable component of cognitive characteristics in dogs could have important implications for understanding the capabilities of different dog breeds.
"The results help us create a more complete picture of breed-specific behaviors and, in the long run, maybe even help us choose the right kind of breeds for the right tasks," Junttila said.
"Our next aim is to investigate whether the results from these cognitive tests can be seen in the owners' descriptions of their dogs' behavior and characteristics, such as impulsivity, aggression, fear, trainability, or excitability. This will provide a lot more insight into what these tests actually measure," she said.
Do you have an animal or nature story to share with Newsweek ? Do you have a question about dogs? Let us know via [email protected]
Junttila, S., Valros, A., Mäki, K. et al. Breed differences in social cognition, inhibitory control, and spatial problem-solving ability in the domestic dog (Canis familiaris) , Sci Rep, December 29 2022, https://doi.org/10.1038/s41598-022-26991-5
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The best dog breeds for car travel according to experts
New research has revealed the best dog breeds for road trips, with Labradors claiming the top spot.
- New research reveals that Labradors are the best dog breed for car travel
- Chihuahuas, French Bulldogs and Poodles all feature in the top five best dog breeds for travel
- Expert dog trainer Adam Spivey shares advice on helping hesitant dogs travel in a car
- An Auto Trader survey found that nearly 30% of us don’t want to share a car with dogs
The Canine Car Report, conducted by Auto Trader analysed advice from 25 pet specialists to discover which dog breed is most commonly named as the best backseat passenger. Labradors came out as the best dog breed for car travel, being named as the most car-compatible breed by 22 canine experts. Famous for being extremely eager to please their owners and very easy to train, Labradors tend to be calm and fuss-free road trip companions.
In second place, with 17 recommendations from canine specialists, is the Chihuahua. As the world’s smallest dog, they are sure to make themselves comfortable in the car thanks to the privilege of having significantly extra legroom! Following in third is the much bigger build of the Golden Retriever, a breed that shares a very similar temperament to that of the Labrador, tipped by 16 experts as being excellent car-travellers.
Apart from the Chihuahua, much of the top list is made up of larger breeds; including Poodles, Dalmatians, Great Danes, Clumber Spaniels, and German Shepherds.
Top Dog Breeds for Car Travel
Expert Advice on Training Your Dog for Car Travel
Auto Trader collaborated with Adam Spivey, Director and Master Trainer at Southend Dog Training, to share his advice on getting your pup ready for car journeys:
- Make sure your dog is calm: Adam explains “The car can represent excitement to a dog which can get them worked up, leading to barking, whining and other stressful behaviours. That is usually because, in the dog’s brain, the destination always results in something fun. So, to counteract this, I would teach the dog that it is calm behaviour that actually leads to the fun they are excited about. I will make sure the dog is sitting by my side when I open the car door, I’ll ensure they are waiting to be invited into the car and then I would put them into an impact crate, as that is the safest way for a dog to travel.”
- Give them plenty of exercise before a journey: Whilst a crate-trained dog will already be familiar with a car crate, it’s important that your dog can work off their pent-up energy prior to a car journey so that they are more likely to relax and rest in the car crate.
- Take regular breaks on a long ride: Adam explains “For puppies, you must take as many breaks as necessary to help with their bladder control; for example, eight-week-old puppies can only hold their bladders for up to an hour. But if you are travelling with an older dog then it is more down to common sense and aligning it with how often you take breaks, but I would recommend every couple of hours so you can both stretch your legs.”
- How to solve car sickness in dogs: Adam recommends the following to help remedy motion sickness:
a) Allow plenty of time between feeding the dog and beginning your car journey
b) Speak to your vet as they might be able to give your dog medication to help prevent motion sickness during a car ride
c) Gradually build up the journey distance – start with small trips and get your dog used to the car’s movements and motions before increasing the length
5. The importance of restraining your dog: For your dog’s safety, your safety and the safety of others, keeping your dog suitably restrained in your car is of utmost importance. Adam explains “A crash-tested impact crate is the safest way for any dog to travel – it is something you see the police use with their dogs. However, if you can’t do that for any reason then, at the very least, you must use a very secure seatbelt attachment for your dog.”
Whatever your dog’s breed, getting your pet to be comfortable with car travel requires a good amount of preparation and planning.
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I’m a dog trainer – the top three breeds if you want a guard dog including one that’s perfect for family life too
- Leanne Hall
- Published : 9:36, 2 Mar 2023
- Updated : 10:58, 2 Mar 2023
- Published : Invalid Date,
A DOG TRAINER has revealed his top three guard dog breeds to go for if you want a pup to protect your family and home.
Will Atherton, from Derbyshire , regularly shares his insight on dog breeds on his TikTok account ( @iamwillatherton ).
In a recent video, the canine behaviourist revealed his favourite pooches that he says make the best pet when it comes to safeguarding the home and family .
It's important to note that all dogs should be properly trained.
He said: "As a canine behaviourist I know there are many different reasons to have a guard dog breed.
The first breed the dog expert recommended was a Cane Corso.
READ MORE ON DOGS
I'm a dog groomer - owners should avoid certain phrases in the salon
Dog expert reveals the three large dog breeds I would recommend as pets
He said: "If you're looking for a guard dog breed to live in your home with you and your family and also make a great pet, it's hard to choose against the Cane Corso."
But, if you are looking for a dog breed that is easy to train to a high standard of personal protection the Belgian Malinois is the one for you, he claimed.
Will added: " If you're looking for a highly trainable guard dog breed that you want to train in personal protection or maybe enter protection sports then you simply have to look at the Belgian Malinois."
The final dog breed the expert recommended was one that looks seriously intimidating.
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He explained: "If you're looking for one of the most intimidating guard dog breeds, a breed that will defend your home to the death, you have to check out the Turkish Kengal."
The large dog breed from Turkey has been bred to look after livestock.
The video has since gone viral with more than 97k views and over 6,000 likes.
People quickly took to the comments section to share their views.
One person wrote: "Kangal all the way. Lucky to have two and they are amazing."
Another commented: "Obvs the Cane Corso was on this list."
"By not mentioning the German Shepard you literally lost all integrity," penned a third.
A fourth added: "I prefer the Dobermann!! fantastic working dog and great company. So devoted to the family!"
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Meanwhile, a fifth claimed: "Cane Corso is just perfect."
"My Cane Corso would just lick them to death," said another.
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- 28 April 2022
Massive study of pet dogs shows breed does not predict behaviour
- Freda Kreier
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Dog enthusiasts have long assumed that a dog’s breed shapes its temperament. But a sweeping study comparing the behaviour and ancestry of more than 18,000 dogs finds that although ancestry does affect behaviour, breed has much less to do with a dog’s personality than is generally supposed 1 .
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Morrill, K., et al. Science 376 , eabk0639 (2022).
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People have been breeding dogs since prehistoric times. The earliest dog breeders used wolves to create domestic dogs. From the beginning, humans purposefully bred dogs to perform various tasks....
There is one study that directly compared different dog breeds' vocal behaviour: Feddersen-Petersen reported that some breeds like Alaskan malamutes and Kleiner Münsterländer have very...
COLUMBUS, Ohio - New research at The Ohio State University College of Medicine and The Ohio State University Wexner Medical Center identifies dog breeds and physical traits that pose the highest risk of biting with severe injury. Doctors want parents of young children to use this information when deciding which dog to own. The study, published in the International Journal of Pediatric ...
Modern dog breeds offer a great opportunity to understand the genetic basis of body plans and size in mammals. In addition to differences in physical traits, breeds vary in disease risk. More than 350 inherited diseases have been described in domestic dogs, many of which predominate in a single breed or a small group of breeds.
Cattle Dogs and Australian Shepherds Best described as brave, loyal, and energetic, these breeds are the top-tier choice when it comes to herding. These dogs are a cowboy's first pick. This amazing breed that was bred to herd also has a piercing stare when they are in a working mode to move livestock or flocks.
Dogs prevent heart attacks and strokes Some of the best scientific studies on dogs relating to heart health have discovered that dogs can dramatically reduce your chances of having a heart attack...
When comparing dog breeds and mutts, distinctive physical traits are not highly correlated to inheritable behavior traits A genetic study of 2,155 purebred and mixed-breed dogs combined with 18,385 owner surveys has challenged existing notions about dog breed stereotypes and personality types.
Research Dog Breeds Leave a comment. Why the Maltese is a great Family Dog Breed in 2022! April 14, 2022 jpatchak. The Maltese is a small dog that weighs four to six pounds (two to three kilograms). Unlike many small dog breeds, the Maltese was not bred from larger breeds. The Maltese has always been known for his small stature.
Dog Breed Report Pennant Banners Dog Breed Research Project by Tied 2 Teaching 4.9 (26) $5.45 PDF These Dog Breed Report Pennant Banners come with over 40 amazing pennants for displaying your research project on the amazing dig breeds that we know and love.
Genetic research confirms your dog's breed influences its personality — but so do you Published: December 11, 2022 2.06pm EST Want to write? Write an article and join a growing community of...
Neutering (including spaying) of male and female dogs in the first year after birth has become routine in the U.S. and much of Europe, but recent research reveals that for some dog breeds, neutering may be associated with increased risks of debilitating joint disorders and some cancers, complicating pet owners' decisions on neutering. The joint disorders include hip dysplasia, cranial cruciate ...
Our latest study includes 1355 dogs from 161 diverse breeds as well as breed varieties and populations from around the world. Using a HighDensity array of 150,000 SNPs we assessed the relationships between the breeds using both distance, as shown on the tree above, and haplotype sharing (Parker et al. 2017).
Most dogs used in research are purchased from Class A dealers, licensed commercial breeders that sell "purpose-bred" dogs specifically for research. They breed beagles, hounds and mongrel dogs and raise the animals on their own premises to fulfill orders for canines ranging from 33-60 pounds that are 6 to 12 months old.
Until now, studies had only assessed that risk in a few breeds. A new, 10-year study by researchers at the University of California, Davis, examined 35 dog breeds and found vulnerability from neutering varies greatly depending on the breed. The study was published in the journal Frontiers in Veterinary Science.
Dog Breeds is a product that will compliment a lesson on animals, community helpers and caring for animals.Included is a 36 piece flashcard set showing image of a dog breed and its name, 3 file folder matching tasks and a worksheet for students to research a dog breed, cut an paste the image of the breed and write information about the breed ...
Hecht, who joined the faculty in January, has published her first paper on our canine comrades in the Journal of Neuroscience, finding that different breeds have different brain organizations owing to human cultivation of specific traits. Using MRI scans from 63 dogs of 33 breeds, Hecht found neuroanatomical features correlating to different ...
Resources to research breeds. We may have just given you homework — sorry. The good news is: You have plenty of resources to look into all types of dogs. ... The AKC has tons of information on dog breeds, including personalities, sizes, life spans, and social and physical characteristics. Friends and family. Ask your friends and family about ...
The German Shepherd is one of the most renowned breeds of dog there is. These dogs are strong, loyal, and are highly response to training. East Siberian Laika The East Siberian Laika is a Russian-type dog that retains many of the traits it inherited from its wild ancestor, the wolf. English Foxhound
Dog Breed Identification Photo Survey and Results More than 5,000 dog experts, including breeders, trainers, groomers, veterinarians, shelter staff, rescuers, and others completed the survey. You are invited to view pictures of the 100 dogs in our study, their actual DNA breed results, and what our survey participants guessed their breeds were.
Scientists at the University of Helsinki in Finland might have an answer. In a study published in the journal Nature Scientific Reports, Saara Junttila and colleagues put 1,002 dogs through a...
New research reveals that Labradors are the best dog breed for car travel. Chihuahuas, French Bulldogs and Poodles all feature in the top five best dog breeds for travel. Expert dog trainer Adam Spivey shares advice on helping hesitant dogs travel in a car. An Auto Trader survey found that nearly 30% of us don't want to share a car with dogs.
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What the research found. Dog breeds are a fascinating window into selective breeding, and some behavior patterns we see in different breed groups—for example, herding and retrieving—are ...
A DOG TRAINER has revealed his top three guard dog breeds to go for if you want a pup to protect your family and home. Will Atherton, from Derbyshire, regularly shares his insight on dog breeds on …
Dog enthusiasts have long assumed that a dog's breed shapes its temperament. But a sweeping study comparing the behaviour and ancestry of more than 18,000 dogs finds that although ancestry...
A considerable subset of dog breeds presented for presumed cPD showed laboratory signs of gluten sensitivity and responded to a gluten-free diet. FIGURE E Discover the world's research