Dogs From Irresponsible Breeders, Puppy Mills Have More Behavioral Problems

behavior problems of puppy mill dogs

Story at-a-glance -

  • Dogs from puppy mills or “less responsible” breeders scored lower in all behavior categories, including trainability, than other dogs
  • Dogs that came from puppy mills or less responsible breeders were more likely to be aggressive, fearful of new objects and have noise phobias
  • Avoid buying dogs from pet stores, puppy mills, irresponsible breeders of any size or online sources (which may also come from puppy mills)

By Dr. Becker

Many well-intentioned pet owners come across an adorable puppy in a pet store or online ad, fall in love and bring the pup home — without giving much thought to where the puppy was raised in his initial weeks of life. These weeks, however, are incredibly important for your dog’s mental and behavioral development, playing a key role in who they become as a full-grown dog.

It is in the best interest of puppies to remain with the mother and littermates until they are at least 7 to 8.5 weeks old. Once you bring a young puppy home, continuing with training and socialization is crucial, but socialization starting at just 3 to 4 weeks old is also important, and this falls on the hands of the rescue organization, shelter or breeder.

Puppies pass through several sensitive stages, the first one generally agreed to be from around 2.5 to 3 weeks through 12 to 14 weeks, during which a puppy's brain is primed to accept new experiences with minimal fear. The experiences the pup has during this sensitive time have the capacity to modify his brain and have a profound impact on his adult character, temperament and behavior.

Unfortunately, puppies that come from puppy mills not only miss out on this crucial socialization but also are neglected their basic needs and subjected to cruel treatment and inhumane living conditions. Many people are unaware that most pet stores receive their puppies from puppy mills, as do many online sellers. However, most smaller scale commercial breeders may be churning out puppies as a commodity, without putting their best interests first.

Dogs From Puppy Mills and Irresponsible Breeders Have More Behavior Problems

Research presented at the British Society of Animal Science conference measured key canine traits in dogs obtained from “responsible” and “less responsible” breeders. Research supervisor Dr. Catherine Douglas, a lecturer in animal science at Newcastle University, said in a press release:1

“The term ‘puppy farm’ is widely used to describe large volume production of puppies but in this study we also included other smaller scale commercial breeders where the dogs’ welfare may not be the first concern. There has been some research around the health problems associated with dogs from puppy farms but very little research into long term effects on adult dog behavior.”

For the study, dog owners were given questionnaires regarding their dog’s breeder as well as their dog’s personality and behavior. Questions included, “At what age did you get the puppy?,” “Did you see the mother?” and whether the dog is aggressive toward strangers or fearful of new things and loud noises. As you might suspect, dogs from less responsible breeders scored lower in all behavior categories, including trainability.2 Dogs that came from puppy farms or less responsible breeders were:3

  • More likely to be aggressive to strangers, members of the household and dogs
  • More likely to be fearful of new objects
  • More likely to have noise phobias
  • More likely to suffer from separation anxiety
  • Less likely to be rated high in trainability

There are many reasons why dogs who get a rough start to life suffer life-long problems. Being separated from their mother too early is one of them. Past research found dogs separated early and purchased from a pet shop showed much greater tendency toward toy possessiveness, fearfulness on walks, attention-seeking, stranger aversion, excessive barking, destructiveness and play biting.4

In addition, the stress felt by the puppy, and the mother during pregnancy, can also influence his life-long behavior and mental state. Karen B. London, Ph.D., a certified applied animal behaviorist and certified professional dog trainer, explained in The Bark:

“Though the results of this study are not surprising, they do confirm that where we get our dogs matters. Acquiring dogs from puppy farms [or any irresponsible breeder] supports an industry that lacks proper safeguards for animal welfare and also makes it less likely that your best friend will be the ideal companion and family member that we all want.”5

Where Is the Best Place to Find Your Family Pet?

About the absolute worst place to find a dog is from a pet store, which is probably supplied by a puppy mill, an online seller (same) or an irresponsible breeder (no matter the size). Your local animal shelter or rescue organization, on the other hand, is home to millions of dogs, including puppies, looking to find a forever home. I strongly suggest starting there in your search for a dog or cat to add to your family. If you have your heart set on a purebred pup — you can still oftentimes find one at a breed-specific rescue.

If you are planning to use a breeder, however, be sure to thoroughly check her background and references to be sure she is responsible and treating the animals with care. A reputable breeder will want to meet and interview anyone interested in buying a puppy, as well as be proud to show you the parents, their living environment and their medical records. I strongly recommend using my breeder’s questionnaire, listed below, as a good starting point.

Always visit a breeder's facility in person and insist on meeting the parents (the mother dog, at a minimum). If the breeder won't show you the living conditions in a separate barn, building or part of the house, be suspicious. You can find more information via the resources below:

Finally, if you believe you have acquired a puppy-mill dog, expect that you will need to work through behavioral issues and engage in an ongoing rehabilitation process. Many pets that end up in shelters or rescues may have come from puppy mills (and been given up due to their behavior) as well, so please don’t give up on them. Positive dog-training techniques often help, while complicated behavior problems may require the services of a veterinary behaviorist.

You may also want to look into a program called A Sound Beginning, which was designed to help rescue dogs, including those that may have started out in puppy mills, and their adoptive guardians learn to communicate effectively and form an unbreakable bond.