Life in puppy mills damages dogs’ mental health, researchers report / Photo: USDA Animal Care Inspection

By Katerina Lorenzatos Makris

“Empty shell with no emotion. In a sort of world of her own. We call her our little autistic girl.”

”Always seems to be in another world. Very stoic. If he were human he’d be autistic.”

“She reminds me of an autistic child…”

The researcher heard it over and over—a common refrain from many of the hundreds of adopters he surveyed

Their dogs were different. The very thing that we think of as most dog about dogs—their infectious enthusiasm—was missing.

As he spoke before a group of scientists, veterinarians, breeders, and animal advocates at The Humane Society of the United States 2011 Purebred Paradox conference in Washington D.C., Dr. Franklin McMillan sometimes had trouble controlling his voice, especially as he described the case of a collie named Freda who had spent her first five years in a commercial breeding establishment (CBE), or “puppy mill.”

“Freda has none of the collie instincts,” the dog’s adopter told McMillan after living with Freda for more than a year. “She hardly ever wags her tail. She loves being brushed—the only time of day she seems to relax around me.  [Adopter’s other dog] tries to get her to play. She just lies down and ignores him.”

McMillan’s voice broke. He shook his head. “As many times as I’ve read this it still gets to me.”

“If you’re buying a dog from a pet store,” he said, “this is what you’re helping to create.”

Study found profound psychological ‘scars’

USDA inspection of licensed Ohio CBE finds matted hair / Photo: USDA

Veterinarian and Director of Well-Being Studies at Best Friends Animal Society, McMillan spent a few minutes describing some of the physical health issues he said are common among dogs in large-scale breeding facilities: dental disease—sometimes to the point where jaws rot away—severely matted hair, missing eyes due to untreated diseases and infections, and wounds from getting caught in the caging material.

The hair matting among dogs in CBEs is particularly insidious, said McMillan. The animal “can’t move because everything’s tugging tightly and just moving around hurts. It’s very painful. And the real nasty stuff is going on underneath there. Dogs simply have an itch and can’t scratch it, or they get the ugly, painful pyodermas [infections] that eat into the skin.”

It’s horrendous and unsightly, McMillan said, but “they [CBE breeders] really don’t care too much what the dogs look like as long as they’re pumping out the puppies.”

Dogs kept in cages with wire instead of solid flooring – feces fall through and accumulate below / Photo: USDA

Foot injuries are also common, he said. “The large majority of puppy mill dogs are small breeds. They’re easy to confine in large numbers, and they make a lot of money for these people and for pet stores. But of course the real sad thing is that these little toy breeds have to walk around on that wire floor [typically used instead of solid flooring],and they actually have to learn how to splay their feet so that they can catch the wires each time they’re stepping. And that’s really sad because of course they get foot injuries beyond just the pain of walking around.”

While such physical ailments are well-known, McMillan believed the psychological effects had not been fully investigated. So he and Deborah Duffy, PhD, and James Serpell, PhD, both of the University of Pennsylvania School of Veterinary Medicine launched a two-year study titled “Mental health of dogs formerly used as ‘breeding stock’ in commercial breeding establishments,” in which they used detailed questionnaires and personal interviews to survey adopters of 1,169 former puppy mill breeding dogs.

McMillan said that he and his colleagues wanted to learn:

  • “What are the psychological and behavioral characteristics of dogs who have been cooped up in these mills?
  • “How many of the dogs show abnormalities?  (“If you look at instances of psychological trauma in people,” he said, “characteristically, no matter what kind of trauma it is, about 10-20%  suffer ongoing psychological scars—PTSD and those types of disorders.”)
  • “How severe are the abnormalities?
  • “How long-lasting are they?
  • “Are they reversible?
  • “How many dogs self-recover? How many need rehabilitation?
  • “What are the most effective treatments?
  • “How does the harm that they suffer affect the adoption relationship and success?”

“We intend… to provide information to the animal behavior and veterinary professions,” said McMillan, “in order to better understand and treat the dogs recovered from CBEs (puppy mills), as well as provide policy makers and legislators with the scientific data to inform their decisions about regulating, reforming, and/or prohibiting the way large-scale dog breeding is conducted.”

Subsequently the study underwent scientific peer review and appeared in the journal Applied Animal Behaviour Science.

“A lot of these dogs carry quite a psychological burden,” McMillan warned, “and if that means they’re going to fail in their homes [after adoption], this is really a bad situation.”

Three cases

Joey was eight years old when he was rescued from a Missouri puppy mill. His adopter felt that perhaps his brain had not developed properly. “As he got older he seemed to regress,” the adopter told McMillan. “I realize all this time he was just existing in this safe place I created for him. Joey did not live life. He just existed.”

Honey Girl had been in her new home for 15 months when McMillan arrived to meet her.

She hid from him, just as she always did when guests came to visit, the dog’s adoptive family members told him. Slowly, Honey Girl had begun to bond with the wife, but not yet with the others.

After six months in his new home, Boomer “stays in corner of backyard, barks constantly,” said his adoptive family. “House breaking a real problem because can’t get within 12 feet of him. [With a] gentle toss of tasty treats, you’d have thought he was being pelted by rocks. Runs from humans. Hasn’t formed any bond with any person in six months.”

‘Staring at walls; if he were human he’d be autistic’

In his presentation at the Washington conference, McMillan read from a list of phrases he had received from adopters when he asked them to describe their former puppy mill breeding dogs:

  • Avoidance
  • Autistic
  • Catatonic schizophrenic
  • PTSD, staring at walls, great fear of new situations
  • Empty shell with no emotion
  • We call her our little autistic girl
  • In a sort of world of her own.
  • Always seems to be in another world.
  • Attention span of a flea
  • Doggie dementia
  • Very stoic
  • If he were human he’d be autistic.
  • Skittish
  • Startles easily
  • On edge
  • Hyper alert
  • Easily spooked or panicked
  • Frightened of everyone or almost everyone, or all the time under any circumstances

Mental states of former puppy mill dogs compared to other dogs

The Best Friends/University of Pennsylvania study compared former puppy mill breeding dogs to a “sample of pet dogs matched for breed, sex, age and neuter status”  by measuring frequency of certain behaviors, reported McMillan, and came up with the following conclusions, among others:

  • Former puppy mill breeding dogs are 215 percent or three times more likely to be fearful of unfamiliar people after two years in the house.
  • They are 34 percent more likely to be fearful of other dogs. In the breeding facilities animals are housed multiply, so McMillan said “you’d think they’d be well-socialized with other dogs,” but they “never can get more than three feet away from another dog, so they get no break, no reprieve from hassles.”
  • They have 128 percent (or two times) more non-social fears of such things as noises, traffic, and bicycles.
  • Unusual and stereotyped behaviors appeared to be more common, with a 77% increase in repetitive behaviors such as spinning.
  • As for cognitive abilities and mental focus, “53% more blank stares are commonly reported in puppy mill dogs,” McMillan said, as if “the light’s on but nobody’s home.”

Other problems that large percentages of the participants reported about their dogs included memory loss, confusion, loss of concentration, irritability, showing little emotion, and sudden unexplained outbursts.

‘Play is not something they get in the puppy mills’

The study also looked at the animals’ interest in play.

“Play is not something they get in the puppy mills,” McMillan pointed out. “They don’t get toys, don’t get playtime.”

Breaking it down into different types of play—play with other dogs and play with humans—the study found that 32% of the former CBE breeder dogs did not know how to play.

Many of the dogs’ reactions resembled those of humans with conditions such as Alzheimers, dementia, ADHD, and autism, said McMillan.

The study’s conclusions

In the published study, the researchers summarized their conclusions as follows:

“When compared with a convenience sample of pet dogs matched for breed, sex, age and neuter status, former CBE breeding dogs were reported as showing significantly higher rates of health problems (23.5% versus 16.6%, P = 0.026). With respect to behaviour, CBE dogs displayed significantly higher rates of fear (both social and nonsocial; ordinal GLM models, P < 0.001), house-soiling (P < 0.001), and compulsive staring (P < 0.005); and significantly lower rates of aggression (toward strangers and other dogs; P < 0.0001), trainability (P < 0.0001), chasing small animals (P < 0.0001), excitability (P < 0.0001), and energy (P < 0.0001).

“By demonstrating that dogs maintained in these environments develop extreme and persistent fears and phobias, possible learning deficits as evidenced by lower trainability, and often show difficulty in coping successfully with normal existence, this study provides the first quantitative evidence that the conditions prevailing in CBEs are injurious to the mental health and welfare of dogs.”

Next study evaluates mental health of CBE puppies

This week McMillan told Animal Issues Reporter that a second study on the mental health of puppy mill dogs—this one focusing on the CBE puppies sold through pet stores—has been completed and a paper about it has been accepted for publication by the Journal of the American Veterinary Medical Association (AVMA).

He is unable to discuss that study’s results now due to the journal’s pre-publication embargo policy, and does not yet have a date for when the paper will be published.

Comments from American Kennel Club (AKC)

Soon after hearing McMillan speak at the Purebred Paradox conference, this reporter requested an interview with the American Kennel Club (AKC) several times through email and telephone voice mail. The group provides registration services for purebred dogs including those at CBEs, and often opposes regulatory legislation that would affect those businesses.  AKC did not reply regarding an interview, and provided the  following response:

“Thanks for contacting us. Below is our statement regarding canine health:


“The American Kennel Club® is a not-for-profit organization which, along with our more than 5,000 licensed and member clubs and its affiliated organizations, advocates for dogs as family companions, advances canine health and well-being, works to protect the rights of all dog owners and promotes responsible dog ownership.

USDA inspection of licensed Ohio CBEs discovered neglect of health issues. / Photo: USDA

“The AKC ‘s high ethical standards have made us the most widely respected registry in the world.  The AKC and responsible breeders aim to preserve and improve the breeds they dedicate their lives to. The AKC has always led the charge in advancing canine health and creating education programs for breeders, such as with the founding of the AKC Canine Health Foundation in 1995. Since that time, more than $25 million has been given to more than 560 research projects at 75 vet schools and research institutes worldwide to improve the health of all dogs.

“The AKC advocates for balanced breeding programs that include genetic testing, pedigree research and conformation and temperament analysis of sire and dam. Potential pet owners should educate themselves about these issues and seek breeders who adequately screen their breeding stock using the available clinical and genetic tests to produce healthy dogs.  Visit the AKC Canine Health Resource Center at for more information on a variety of programs and services as well as other organizations that can help breeders produce healthy puppies for the enjoyment of future generations of dog owners.

“For More Information Visit the AKC Canine Health Resource Center at”

This week Animal Issues Reporter again requested an interview with the American Kennel Club (AKC) regarding the study and has not yet received a reply.

Also on this topic:

Reporter asks USDA to review study on damaged mental health of puppy mill dogs

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 Katerina Lorenzatos Makris is a career journalist, author, and editor. Credits include hundreds of articles for regional wire services and for  outlets such as National Geographic Traveler, The San Francisco Chronicle, Travelers’ Tales, NBC’s, and (Animal Policy Examiner), a teleplay for CBS-TV, a short story for The Bark magazine, and 17 novels for Avon, E.P. Dutton, Simon and Schuster, and other major publishers.

Together with coauthor Shelley Frost, Katerina wrote a step-by-step guide for hands-on, in-the-trenches dog rescue, Your Adopted Dog: Everything You Need to Know About Rescuing and Caring for a Best Friend in Need (The Lyons Press).