Tag Archives: University of California

When Should You Neuter Your Dog to Avoid Health Risks?

Posted on July 17, 2020 | Leave a comment

10 year study on neutering 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.

Source: UC Davis

I may be neurotic…but that makes me a good dog mom

Posted on January 18, 2015 | 1 comment

I am conscientious and reliable. From an early age, I also had a strong sense of self-preservation when it came to putting myself in potentially dangerous situations. To some, that makes me neurotic. However, that’s not such a bad thing, according to new research out of the University of California at Berkeley and California State University.

Helicopter parenting may not be the best strategy for raising independent kids. But a healthy measure of clinginess and overprotectiveness could actually be advantageous when rearing dogs and cats, according to new research from UC Berkeley and California State University, East Bay.

A Web-based survey of more than 1,000 pet owners nationwide analyzed the key personality traits and nurturing styles of people who identified as a “cat person,” a “dog person,” “both” or “neither.”

Surprisingly perhaps, those who expressed the greatest affection for their pets also rated among the most conscientious and neurotic, suggesting that the qualities that make for overbearing parents might work better for our domesticated canine and feline companions, who tend to require lifelong parenting.

“The fact that higher levels of neuroticism are associated with affection and anxious attachment suggests that people who score higher on that dimension may have high levels of affection and dependence on their pets, which may be a good thing for pets,” said Mikel Delgado, a doctoral student in psychology at UC Berkeley and co-author of the study, recently published in the Journal of Applied Animal Welfare Science.

The results echo those of a 2010 study by University of Texas psychologist Sam Gosling, a UC Berkeley graduate, which showed dog owners to be more extroverted, but less open to new experiences, and cat owners to be more neurotic, but also more creative and adventurous.

While previous studies have focused on people’s attachment to their pets, this is the first U.S. study to incorporate the principles of human attachment theory – which assesses the bond between parents and children or between romantic partners — with pet owners’ personality types, including whether they identify as a “dog person” or “cat person.”

It is also the first to find a positive correlation between neuroticism, anxious attachment and the care of and affection for pets, said CSU-East Bay psychologist Gretchen Reevy, co-author of the paper and a graduate of UC Berkeley.

Delgado and Reevy recruited male and female pet owners of all ages through the Craigslist classified advertising website, their personal Facebook pages and pet-related pages on the Reddit news and social networking site. Nearly 40 percent of those surveyed said they liked dogs and cats equally, while 38 percent identified as dog people and 19 percent as cat people. A mere 3 percent favored neither.

The online questionnaire was based on both human and animal attachment assessments, including one that measures the “Big Five” overarching human characteristics (openness, conscientiousness, extraversion, agreeableness and neuroticism). Pet owners were also rated according to the Lexington Attachment to Pets Scale, which measures affection for pets, and the Pet Attachment Questionnaire, which gauges “anxious attachment” and “avoidant attachment.”

People who score high on anxious attachment tend to need more reassurance from the objects of their affection, and in the survey those tended to be younger people who chose a cat as a favorite pet.

Conversely, people who rate highly on avoidant attachment, which refers to a less affectionate and more withdrawn temperament – and can inspire such rejoinders as “commitment-phobe” in romantic relationships – are much less needy. Both dog and cat lovers scored low on avoidant attachment, suggesting both personality types enjoy close relationships with their pets.

“We hypothesized that more attentive and affectionate pet owners would receive higher affection scores and lower avoidant attachment scores, as higher levels of avoidant attachment would suggest distancing behaviors between the individual and their pet,” Delgado said.

Delgado and Reevy plan to dig more deeply into the link between neuroticism and affection for and dependence on one’s pet.

“We will investigate further whether greater affection for and greater anxious attachment to one’s pet, and neuroticism, are associated with better care and understanding of the pet’s needs,” Reevy said.

Source: UC Berkeley media release

Kathleen Crisley, specialist in dog massage, rehabilitation and nutrition/food therapy, The Balanced Dog, Christchurch, New Zealand

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Tagged anxious attachment, Berkeley, California State University, cat person, dog person, helicopter parenting, human attachment theory, neurotic, UC Berkeley, University of California

Jealousy in dogs is real

Posted on August 10, 2014 | Leave a comment

Dogs can act jealous (is this really news to most dog owners?). Well, researchers have taken steps to scientifically prove that jealousy exists. They undertook this research because researchers studying emotion have argued for years whether jealousy requires complex cognition or that jealousy is a social construct not linked to physiology and psychology the way emotions like fear and anger are…

Emotion researcher Christine Harris, professor of psychology at UC San Diego, with Samwise, one of three border collies to inspire the study on dog jealousy. Photo by Steve Harris.

The research, published in the journal PLoS ONE, by University of California San Diego psychology professor Christine Harris and former honors student Caroline Prouvost is the first experimental test of jealous behaviors in dogs.

The findings support the view that there may be a more basic form of jealousy, which evolved to protect social bonds from interlopers.

Harris and Prouvost show that dogs exhibit more jealous behaviors, like snapping and pushing at their owner or the rival, when the owner showed affection to what appeared to be another dog (actually a stuffed dog that barked, whined and wagged its tail). Dogs exhibited these behaviors more than if the same affection was showered on a novel object and much more than when the owner’s attention was simply diverted by reading a book.

“Our study suggests not only that dogs do engage in what appear to be jealous behaviors but also that they were seeking to break up the connection between the owner and a seeming rival,” Harris said. “We can’t really speak to the dogs’ subjective experiences, of course, but it looks as though they were motivated to protect an important social relationship.”

Since there had been no prior experiments on dog jealousy, the researchers adapted a test used with 6-month-old human infants. They worked with 36 dogs in their own homes and videotaped the owners ignoring them in favor of a stuffed, animated dog or a jack-o-lantern pail. In both these conditions, the owners were instructed to treat the objects as though they were real dogs – petting them, talking to them sweetly, etc. In the third scenario, the owners were asked to read aloud a pop-up book that played melodies. Two independent raters then coded the videos for a variety of aggressive, disruptive and attention-seeking behaviors.

Dogs were about twice as likely to push or touch the owner when the owner was interacting with the faux dog (78 percent) as when the owner was attending to the pail (42 percent). Even fewer (22 percent) did this in the book condition. About 30 percent of the dogs also tried to get between their owner and the stuffed animal. And while 25 percent snapped at the “other dog,” only one did so at the pail and book.

The “other dog” – the stuffed, animated pooch used in the experiment. Photo by Caroline Prouvost.

Did the dogs believe the stuffed animal was a real rival? Harris and Prouvost write that their aggression suggests they did. They also cite as additional evidence that 86 percent of the dogs sniffed the toy dog’s rear end during the experiment or post-experiment phase.

“Many people have assumed that jealousy is a social construction of human beings – or that it’s an emotion specifically tied to sexual and romantic relationships,” Harris said. “Our results challenge these ideas, showing that animals besides ourselves display strong distress whenever a rival usurps a loved one’s affection.”

Source: UCSD media release

Cleft palate in dogs

Posted on April 13, 2014 | 1 comment

UC Davis School of Veterinary Medicine researchers have identified the genetic mutation responsible for a form of cleft palate in the dog breed Nova Scotia Duck Tolling Retrievers.

Photo by Danika Bannasch/UC Davis

They hope that the discovery, which provides the first dog model for the craniofacial defect, will lead to a better understanding of cleft palate in humans. Although cleft palate is one of the most common birth defects in children, affecting approximately one in 1,500 live human births in the United States, it is not completely understood.

By conducting a genome-wide study of this breed with a naturally occurring cleft palate, researchers identified a mutation responsible for the development of cleft palate. Dogs with this mutation also have a shortened lower jaw, similar to humans who have Pierre Robin Sequence. The disorder, a subset of cleft palate, affects one in 8,500 live human births and is characterized by a cleft palate, shortened lower jaw and displacement of the tongue base.

Cleft palate condition occurs when there is a failure in the formation of the secondary palate, which makes up all of the soft palate and the majority of the hard palate.

The team have published their study in the journal PLOS Genetics.

Source: UC Davis media release

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Tagged cleft palate, Davis, Duck tolling retriever, Nova Scotia, PLoS Genetics, University of California

18,000 years and counting

Posted on November 22, 2013 | 1 comment

Wolves likely were domesticated by European hunter–gatherers more than 18,000 years ago and gradually evolved into dogs that became household pets, say a research team based at the University of California Los Angeles.

“We found that instead of recent wolves being closest to domestic dogs, ancient European wolves were directly related to them,” said Robert Wayne, a professor of ecology and evolutionary biology in UCLA’s College of Letters and Science and senior author of the research. “Europe is where the oldest dogs are found.”

The team’s genetic analysis is published 15 November issue of the journal Science.

The researchers studied 10 ancient “wolf-like” animals and eight “dog-like” animals, mostly from Europe. These animals were all more than 1,000 years old, most were thousands of years old, and two were more than 30,000 years old.

The biologists studied the mitochondrial DNA of the animals, which is abundant in ancient remains. By comparing this ancient mitochondrial DNA with the modern mitochondrial genomes of 77 domestic dogs, 49 wolves and four coyotes, the researchers determined that the domestic dogs were genetically grouped with ancient wolves or dogs from Europe — not with wolves found anywhere else in the world or even with modern European wolves. Dogs, they concluded, derived from ancient wolves that inhabited Europe and are now extinct.

Wayne said that that the domestication of predatory wolves likely occurred among ancient hunter–gatherer groups rather than as part of humans’ development of sedentary, agricultural-based communities.

“The wolf is the first domesticated species and the only large carnivore humans ever domesticated,” Wayne said. “This always seemed odd to me. Other wild species were domesticated in association with the development of agriculture and then needed to exist in close proximity to humans. This would be a difficult position for a large, aggressive predator. But if domestication occurred in association with hunter–gatherers, one can imagine wolves first taking advantage of the carcasses that humans left behind — a natural role for any large carnivore — and then over time moving more closely into the human niche through a co-evolutionary process.”

There is a scientific debate over when dogs were domesticated and whether it was linked with the development of agriculture fewer than 10,000 years ago, or whether it occurred much earlier. In the new Science research, Wayne and his colleagues estimate that dogs were domesticated between 18,000 and 32,000 years ago.

The research was federally funded by the National Science Foundation.

You can read more about the team’s research in this UCLA media release.

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Tagged College of Letters and Science, dog origins, domestic dogs, Europe, Los Angeles, National Science Foundation, Robert Wayne, science, UCLA, University of California, University of California Los Angeles, wolves