Approximately one year ago I told you about animal welfare advocate, Dr. Frank McMillan’s study documenting the increased incidence of behavioral abnormalities in adult dogs rescued from puppy mills. This important research provided scientific documentation that these animals come part and parcel with a plethora of negative behaviors.
Dr. McMillan has done it again. This time, his research focuses on puppies purchased from pet stores, the vast majority of which are born in commercial breeding facilities (aka, puppy mills). The most recent edition of the Journal of the American Veterinary Medical Association features Dr. McMillan’s research documenting the behavioral differences between puppies obtained from pet stores and those obtained from noncommercial (non-puppy mill) breeders.
As Dr. McMillan states,
It has long been an article of faith among veterinarians and canine professionals that dogs obtained as puppies from pet stores have a higher prevalence of health and behavioral problems. However there has been a dearth of empirical studies to support this notion.
Research results
Dr. McMillan and his fellow researchers found that pet store dogs received less favorable scores than breeder-obtained dogs for almost every behavior variable measured. In no behavioral category did the pet store group achieve a more desirable score than the breeder group.
Pet store dogs were significantly more likely to exhibit aggression towards human family members, unfamiliar people, and other dogs. They were also more likely to have separation anxiety and touch sensitivity. Additionally, dogs originating from pet stores were more excitable, energetic, and attention seeking and generally less trainable. Lastly, they exhibited higher frequencies of negative behaviors such as escaping from the home, mounting of people and objects, and urinating and defecating in the house.
The authors theorize that stress experienced in a commercial breeding/puppy mill environment during the formative stages of a pet store puppy’s life negatively impacts brain development. There is also evidence that prenatal stress (stress experienced by the pregnant female) can alter normal behavioral development of her offspring. Specifically mentioned stressors include confinement to a small space, extreme temperatures, negative interactions with kennel staff, inability to regulate exposure to negative stimuli, and limited access to positive interactions with humans.
The researchers acknowledged that those who purchase puppies from pet stores might use different methods of training compared to those who purchase from noncommercial breeders. The current study did not investigate this variable.
I wholeheartedly applaud this terrific research. The more scientific substantiation we have to underscore the insanity of purchasing puppies from pet stores the better.
Have you lived with and/or trained a pet store pup? If so, how did it go?
Best wishes,
Nancy Kay, DVM
Diplomate, American College of Veterinary Internal Medicine
Author of Speaking for Spot: Be the Advocate Your Dog Needs to Live a Happy, Healthy, Longer Life
Author of Your Dog’s Best Health: A Dozen Reasonable Things to Expect From Your Vet
Recipient, Leo K. Bustad Companion Animal Veterinarian of the Year Award
Recipient, American Animal Hospital Association Animal Welfare and Humane Ethics Award
Recipient, Dog Writers Association of America Award for Best Blog
Recipient, Eukanuba Canine Health Award
Recipient, AKC Club Publication Excellence Award
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Please visit http://www.speakingforspot.com to read excerpts from Speaking for Spot and Your Dog’s Best Health. There you will also find “Advocacy Aids”- helpful health forms you can download and use for your own dog, and a collection of published articles on advocating for your pet’s health. Speaking for Spot and Your Dog’s Best Health are available at www.speakingforspot.com, Amazon.com, local bookstores, and your favorite online book seller.
Last week, in honor of Pet Cancer Awareness Month, I provided some
The month of May has been declared Pet Cancer Awareness Month. While I’m not altogether sure who determines such things, in honor of this declaration I present to you a good deal of information that I’m certain will be useful should your four-legged family member develop cancer.


Until a few years ago, I’d always nodded in agreement with the recommendation to neuter dogs (particularly females) not intended for breeding purposes between six months and one year of age. Spaying and castrating within this age window reduces the risk of accidental pregnancies, behavioral issues (primarily in male dogs), and breast cancer later in life. While I don’t dispute the validity of these cause and effect assessments, a growing body of evidence has caused me (and plenty of other veterinarians) to seriously rethink neutering recommendations.
Gross title, I know, particularly for those of you not in a medical profession. It takes a strong stomach to read about vomit (and poop, for that matter), but I hope you will take a few minutes to ponder the following information. It just may prove beneficial in caring for your pet’s health.
Do you give your dog bully sticks as treats? If so, you may be surprised by some information recently released by researchers from Tufts University and the University of Guelph. They have discovered that people who feed bully sticks are unknowingly providing extra calories and potentially harmful bacteria to their dogs.
Am I feeling frustrated and disappointed? You bet I am after reading an article titled, “



