Animal shelter workers sometimes mistakenly label dogs as pit bulls—an error that can have potentially devastating consequences.
“Animal shelter staff and veterinarians are frequently expected to guess the breed of dogs based on appearance alone,” says Julie Levy, professor of shelter medicine at the University of Florida College of Veterinary Medicine.
“Unlike many other things people can’t quite define but ‘know when they see it,’ identification of dogs as pit bulls can trigger an array of negative consequences, from the loss of housing, to being seized by animal control, to the taking of the dog’s life,” she says.
“In the high-stakes world of animal shelters, a dog’s life might depend on a potential adopter’s momentary glimpse and assumptions about its suitability as a pet. If the shelter staff has labeled the dog as a pit bull, its chances for adoption automatically go down in many shelters.”
The past few decades have brought an increase in ownership restrictions on breeds including pit bulls and dogs that resemble them based on assumptions that they are inherently dangerous, that such dogs can be reliably identified, and that the restrictions will improve public safety.
The study, published in the Veterinary Journal, focuses on how accurately shelter staff identifies dogs believed to be pit bulls. “Pit bull” is not a recognized breed, but a term applied to dogs derived from the heritage breeds American Staffordshire terrier or Staffordshire bull terrier. The purebred American pit bull terrier is also derived from these breeds and is often included in the loose definition of “pit bull.”
“If the shelter staff has labeled the dog as a pit bull, its chances for adoption automatically go down.”
The research team evaluated breed assessments of 120 dogs made by 16 shelter staff members, including four veterinarians, at four shelters. Staff members all had at least three years of experience working in a shelter environment. The researchers then took blood samples from the dogs, developed DNA profiles for each animal, and compared the DNA findings against the staff’s initial assessments.
“We found that different shelter staffers who evaluated the same dogs at the same time had only a moderate level of agreement among themselves,” Levy says. The results also show that while limitations in available DNA profiles make absolute breed identification problematic, when visual identification was compared with DNA test results, the assessors in the study fared even worse.
High stakes for dogs and owners
Dogs with pit bull heritage breed DNA were identified only 33 to 75 percent of the time, depending on which of the staff members was judging them. Conversely, dogs lacking any genetic evidence of relevant breeds were labeled as pit bull-type dogs from 0 to 48 percent of the time.
“Essentially we found that the marked lack of agreement observed among shelter staff members in categorizing the breeds of shelter dogs illustrates that reliable inclusion or exclusion of dogs as ‘pit bulls’ is not possible, even by experts,” Levy says.
“These results raise difficult questions because shelter workers and veterinarians are expected to determine the breeds of dogs in their facilities on a daily basis. Additionally, they are often called on as experts as to whether a dog’s breed will trigger confiscation or regulatory action. The stakes for these dogs and their owners are in many cases very high.”
Dog breeds contain many genetic traits and variants, and the behavior of any individual dog is impossible to predict based on possible combinations.
“A dog’s physical appearance cannot tell observers anything about its behavior. Even dogs of similar appearance and the same breed often have diverse behavioral traits in the same way that human siblings often have very different personalities,” Levy says.
Even though most pet dogs are of unknown mixed breeds, there is a natural inclination among pet owners to speculate on what their dog’s breed heritage might be.
“This has fueled an entire industry of pet dog DNA analysis,” Levy says. “These tests are fun, but they won’t help predict behavior or health traits. Shelters and veterinary clinics are better off entering ‘mixed breed’ or ‘unknown’ in their records unless the actual pedigrees are available.”
As for legal restrictions on dogs based on their appearance, public safety would be better served by reducing risk factors for dog bites, such as supervising children, recognizing canine body language, avoiding an unfamiliar dog in its territory, neutering dogs, and raising puppies to be social companions.
Other researchers from the University of Florida and from Michigan State are coauthors of the study. Maddie’s Fund and the Merial Veterinary Scholars Program funded the work.
Source: University of Florida