Study Shows Purebred Dogs Healthier Overall than Mixed Breeds

Dr. Kiersten Forsyth, DVM cardiology resident at Purdue and lead author of the recent paper from the Dog Aging Project discussing findings on health in our canine companions, joins host Laura Reeves with the details, which are not necessarily the same as what you might have heard.

“The Dog Aging Project is this really cool community science project,” Forsyth said. “Essentially, there are some researchers that are involved at a few different universities, but the main people that are involved in this project are the dog owners themselves. People can nominate their dog to participate.

“It is a longitudinal observational study, which basically means as a pet owner, once a year you fill out this really big survey that tells all about your dog, what their history is as far as their health, but also where they live, what kinds of things they do, the environment they’re in. And that information for one dog might not tell us a lot, but when we have tens of thousands of dogs participating, we can pull a lot of information from this.

“And so once a year, you get to refill out this survey, and we can follow these dogs throughout their lifetime to see what changes, what they’re exposed to and our real goal is to learn more about all of these dogs in the U.S., but also what makes some dogs live longer than other dogs and can we get more information about aging in these dogs?

“For the specific research part that I was involved in, we were looking at all of the dogs who were enrolled in the study during the year of 2020. We had 27,541 dogs included. So, a huge number.

“Of those, about 50 percent of them were mixed breed dogs and 50 percent of them were purebred dogs. We tried to look at what the 25 most common or popular dog breeds were that made up the dog aging project pack at that point in time and then really focused on those top 25 breeds to then say, ‘okay for these specific breeds, what are the most common medical conditions that their owners are reporting their dog to have experienced in their lifetime’.

“So, for each breed, we came up with a list of their 10 most commonly reported conditions, and then we looked to compare how those changed between different breeds and between the mixed breed population and the purebred population to see is there really a difference in the amount of medical conditions that a dog gets if they’re a purebred dog versus being a mixed breed dog.

“When we looked at it, one of the things we were wondering was, do purebred dogs have more disease than mixed breed dogs? And we found, no, that’s not the case. In fact, it might even be slightly suggested into the opposite, ’cause we looked at, of all of these dogs, how many of them did not have any health conditions reported?

“These are our healthy dogs. Nothing has been reported to be wrong with them. And we found that 22 percent of the purebred dogs had no reported medical conditions. And just under 21 percent of the mixed breed dogs had no medical conditions. So, there was really a 1.6 percent difference between the two of them, which is not a huge difference, but it was actually statistically significant that the purebred dogs were actually more likely to have no owner-reported medical conditions than our mixed breed dogs.

“It’s really not more likely to have disease in your purebred dogs.

“Now, specific breeds may be more likely to have specific conditions. And that goes along with, you know, I do a lot of stuff with the heart. I know that if we think of degenerative valve disease, Cavaliers come to the top of your mind, or if you think of dilated cardiomyopathy, Dobermans come to the top of your mind. And we’re not saying that certain breeds aren’t more prone to very specific diseases or medical conditions, but as a whole, being purebred doesn’t show a higher reporting of medical conditions compared to mixed breed.

“It’s turning out that common things happened commonly, where even though we’re looking at these purebred dogs, where you might think they’re prone to very specific diseases or medical conditions, it still is things like dental disease, dog bites from other dogs. Those are still some of the things that are showing up frequently across breeds, not just with one specific breed.”