The number of dogs entering US shelters has reached an all-time low, and the number of purebred dogs found in shelters has dropped to about five percent, according to a study just released by the National Animal Interest Alliance (NAIA), an advocacy organization for responsible animal ownership.

NAIA President Patti Strand said the study shows “tremendous progress” in eradicating dog overpopulation and substantially reducing the number of shelter deaths which occurred in the past due to indiscriminate or accidental breeding. Strand credited animal sheltering groups for their ongoing campaigns encouraging pet owners to select their pets carefully, spay or neuter their pets and understand the lifelong commitment ownership requires.

“As a result of these efforts, 83 percent of household dogs are neutered, and tens of thousands carry microchips or tattoos that help shelters return lost pets to their owners,” Strand said.

“The NAIA study results are very encouraging,” said Sheila Goffe, Director of Government Relations for the American Kennel Club. “It is the most extensive survey on this subject to date and it shows that dogs identified as purebreds are rare in American shelters today, an outcome that responsible breeders, rescuers and AKC have worked decades to achieve.”

There are downsides however from the lack or purebred dogs ending up in shelters. Pure breed dogs can sometimes be sold to unsuspecting customers that come from puppy mills, especially if purchased over the internet.

In 2011, The Humane Society of the United States released results from its investigation into Purebred Breeders, LLC. It found many suppliers for one of the nation’s largest online puppy sellers were inhumane commercial breeding facilities known as puppy mills, where dogs are often stacked in cramped wire cages, with no exercise, veterinary care, socialization, or human companionship.

Puppy’s purchased online can also come from overseas including countries where there are few or even no animal cruelty or welfare laws. Breed rescues that import dogs from other countries can also cause problems. According to the Centers for Disease Control, four Northeastern states recently received more than 30 rescue dogs and cats from Egypt for adoption in the U.S., including one dog with rabies.

“Importing dogs that may be infected with rabies, other zoonotic and/or infectious diseases puts American citizens and animals at risk of illness or death and should not be allowed,” Strand said.