In March, the Department of Agriculture proposed a new rule that could eliminate some of the worst practices at puppy mills — large commercial puppy breeding operations that often keep hundreds of dogs in crowded and inhumane conditions.

Puppy mills exist to churn out puppies for the pet market, selling them online and through pet stores nationwide. Currently, there are tens of thousands of breeding dogs trapped in puppy mills, and at least 2,500 commercial dog breeders, many of which would meet the description of a puppy mill, are licensed by the USDA.