Raw dog diets aren’t a new concept (many dogs were fed uncooked meat before kibble was introduced in the 1950s), but the raw foodist niche in the pet-care industry is a relatively recent development. And some veterinarians are skeptical.

Dr. Ann Hohenhaus, a spokeswoman for the Animal Medical Center in Manhattan, said that she was not inclined to recommend a raw-food diet for her patients. “There are too many risks associated with it,” she said, among them sanitary issues (the food carries microbes that could harm either the pet or humans in the household) and the possibility that the diet is not nutritionally balanced.

And while some dog owners make the argument that, in the wild, these animals would have eaten raw food, she pointed out: “Dogs have been domesticated and living with us for, some of them, centuries. A raw food diet is not necessarily going to agree with these animals whom we’ve imposed our lifestyles on.”

Still, those who believe in the power of raw food are hard to dissuade.

Geoff Bowers, founder of New Zealand-based K9 Natural, a line of raw dog food, suspects the burgeoning raw-pet-food market reflects the broader interest in healthful eating. “People are looking for more and more natural products,” he said, “and since pets are considered members of the family, they want healthier options for them, too.” Mr. Bowers, a former police-dog trainer, said he converted to raw feeding after studying Alaskan wolf packs, because he became convinced that “nature provides the perfect food” for dogs.

Phil Klein, owner of the East Village holistic pet-supply store Whiskers, started selling raw food in 1988. Known to his fans as the Dogfather, Mr. Klein has published articles on the importance of feeding animals natural cuisine and keeps thick binders of thank-you notes from local pet owners who swear the raw diets he recommended cured their charges of everything from dandruff to diabetes.