Vets have advised against non-meat and non-dairy diets for domestic pets despite the increasing popularity of a vegan product designed to cover cats' and dogs' dietary needs.
Vegan Pet was developed by a Victorian health food maker to include the essential nutrients cats and dogs would miss out on in a vegan diet.
Derived from entirely non-dairy and non-meat sources and designed with the help of a Murdoch University professor, studies have shown it can provide the short-term dietary needs of domestic pets.
It is sold in Queensland at the ethical alternative pet food store Complete Pet Company in Keperra. Owner and operator Jenny Golsby says vegan and vegetarian pet foods are becoming more popular as pet owners search out ethical alternatives to mainstream pet food.
Despite the product's growing popularity and dietary provisions, veterinarians still hold concerns a non-meat diet could harm domestic animals, especially cats.
Australian Small Animal Veterinary Association president David Neck said he would immediately advise owners against feeding their animals an exclusively non-meat and non-dairy diet.
Dr Neck was particularly concerned with how a non-meat diet could provide carnivores, such as cats, "a complete and satisfying" meal.
"Millions of years of evolution have dictated what is best to go into these animals, and [some pet owners] trying to change that in the course of one generation does not make sense to me," he said.
"It really is a concept I struggle to come to terms with, that you would take what is the natural diet of such an animal and alter it in such a radical way.
"I can tell you from my experience with cats and dogs they don't have any ethics about where their food source is derived from.
"If a vegan pet owner is making that decision on behalf of a pet that they own, they should perhaps consider the reasons they have that pet."
Vegan Pet creator Sandy Anderson said she understood the concern veterinarians had with animals being fed vegan food.
Her decision to develop dry food and tinned food products was motivated by the concerns she had seeing her friends feed their animals vegan food not designed for pets.
"I realised the animals weren't getting everything they needed having studied a basic nutrition course," Ms Anderson said.
"So what I did then, for their good, was try and find out whether you can have vegan cat food [with the proper nutrients]."
Ms Anderson developed the products with the help of Nick Costa, head of biochemistry and nutrition at Murdoch University's School of Veterinary and Biomedical Science, ensuring the food met the needs for complete and balanced diet, according to the dietary requirements tabled by the Association of American Feed Control Officials.
The food passed tests for short-term effects, palpability and digestibility.
Concerned with the quality of pet food sold by mainstream distributors, Ms Anderson said the proof of the food's suitability for animals was in their reaction to it.
"Some animals have been on it for eight or nine years and they are still thriving on it," she said.
"People say that cats are carnivore and they should be fed meat, which they should.
"But my theory is if you can feed an equivalent that the cat enjoys equally and it supplies everyone of those nutrients in the meat source, what harm is being done?"
Professor Costa said long-term studies needed to be conducted on the product and he personally believed a meat diet was preferable for cats.
But he said the product was a viable alternative for people wanting to feed their animal a vegan diet.
"What it does do, through Sandy's efforts, is for those people who are vegans, and who eschew red meat completely, and meat products generally, then this gives them an alternative that has complete and balanced nutrient profile that has been partially tested in terms of digestibility and palatability," Professor Costa said.
"What it hasn't been tested for is long-term trials, where you can see if it is affecting reproduction long term, heart function long term, through taurine, or whether it is affecting visual processes long term.
"But in support of the food it has been going a decade and if those systems were problematic Sandy would have heard from people who had been suing it by now."
Dr Neck believes there is another solution for animal lovers keen to feed their animals a vegan diet.
"If you're a vegan, and you have ethical concerns about feeding animal-derived protein to your pet, well I could probably recommend a rabbit or a guinea pig as a pet, that you can source their nutrients from," he said.
"Rather than make ethical choices for an animal."
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