Los Angeles may soon be home to a lot more vegan dogs.

Not at barbecues, though one imagines that meat-free franks are popular in a fitness mecca where vegan meals are easy to come by. No, the dogs in question are the 33,000 pooches that each year enter the city’s six animal shelters and are fed – for now, at least – traditional kibble composed mostly of turkey, chicken and lamb byproducts.

Those dogs’ dinners could be swapped out for a plant-based food under a proposal before the Los Angeles City Board of Animal Services Commissioners. The change, which commissioners could decide Tuesday, would make the city’s shelter system the first in the nation to feed its canine residents a vegan diet, according to its chief veterinarian.

Supporters, who include musician and animal rights activist Moby and the feminist lawyer Lisa Bloom, say that is one of the selling points: To make L.A. shelter dogs the vanguard of a meat-free movement.

“If we adopt this, it’s one more thing that proves to the world that Los Angeles really is the progressive capital,” Moby, whose real name is Richard Hall, testified at the board’s meeting last month.

The idea was proposed by Commissioner Roger Wolfson, a Hollywood screenwriter who cited research that he contended shows vegan diets “eliminate” many health problems in dogs, which are omnivores. But he said rethinking the dogs’ meals is about far more sweeping matters – the environmental effect of a meat industry that produces the main ingredients in lots of dog food and the ethics of feeding animals to animals.

“We have to embrace the fact that the raising and killing of animals for food purposes must only be done if we have absolutely no other choice,” Wolfson said at the meeting, according to a recording published on a county website. “This is about the long-term survival of every man, woman and child in this room, and all of the people in our lives.”

The city’s chief veterinarian, Jeremy Prupas, was not convinced. In a report to the commission, he recommended rejecting the proposal, saying that it could deprive dogs of sufficient protein, calcium and phosphorus and that it could be inadequate for injured, pregnant or lactating pups. Prupas said he’d consulted three clinical nutritionists at veterinary medical schools, one shelter medicine specialist and a veterinary toxicologist who works with a pet food company. None endorsed vegan dog diets, he testified.

“We recognize that individual, privately owned dogs can do well on a wide variety of diets (Commercial, Vegetarian, Organic, Grain-free, Gluten-free, Raw, and Vegan),” Prupas wrote in his report. “However, that is quite a different population than the group of dogs we encounter daily in our animal shelters.”

It would be easy to dismiss all this as a particularly Los Angeles debate. But confusion about the best food for dogs is real, in part because of a booming specialty pet food market.

Dog foods have long been rooted in meat byproduct, which is a euphemism for the castoff animal body parts that slaughterhouses cannot or do not sell to humans. Many of those contain substantial amounts of grain, too.

Nowadays, more companies are pushing grain-free or “all-meat” products, with some suggesting that they’re more suitable for animals that descended from wolves. Many veterinarians dismiss this as a marketing ploy that’s not supported by science, noting that dogs have evolved to digest starch better than their wild cousins. But many veterinary nutritionists also say that while dogs – whose protein needs are lower than those of cats – can do well on vegetarian or vegan diets, commercial options haven’t been widely tested.

“We know a lot about dog nutrition, but there are unknowns as well,” Lisa M. Freeman, a board-certified veterinary nutritionist and a professor at Tufts University, told the New York Times recently. “We want them to be eating a diet that is nutritionally balanced. That means it has all the proteins, vitamins and minerals that they need in the correct ratios and with the best quality control. It isn’t easy to formulate a high-quality diet for dogs, and it’s particularly difficult with a vegan diet.”

Prupas’ report cited two other reasons for keeping L.A. shelter dogs on their current food: Price and poop. The city pays $0.87 per pound for Canidae Life Stages, and the only vendor contracted to the city charges four times as much for a vegan product, it said. What’s more, Prupas wrote, a vegan diet higher in fiber could “lead to increased fecal bulk and frequency of bowel movements,” leading to more cleanup work for shelter staffers.

That argument precipitated several diarrhea-related comments in nearly two hours of testimony at the commission’s Nov. 28 meeting, where pro-vegan voices dominated. Several pet owners, including Bloom, insisted that their vegan dogs had never suffered from digestive problems. Wolfson said the same of his dogs, and he said he’d secured commitments from two plant-based dog food companies to match the price of the city’s current kibble.