Nutritionists have found that at least two slow-cooked, man-made vegan diets provide adequate nutrition for dogs.
“The vegan and human food trend is becoming more common for dogs. “Because people feed them (vegan products) to their animals, it’s important that they are tested like any other food and that we know if they are safe, complete and balanced,” said study co-author Kelly Swanson, who led the research.
Her team tested two vegan human foods (with and without a grain component) and compared them to a plain but high-quality chicken dog food from a leading brand. For three weeks, the researchers fed the dogs this diet and took blood and feces samples. From them, they assessed changes in their organism and microbiome. Then the results described in the Journal of Animal Science.
The team also analyzed the feeds themselves. The vegan diet was a mix of whole foods such as lentils, chickpeas, sweet potatoes, squash, apples, blueberries, peas and carrots. The analysis confirmed that both the vegan diet and the chicken-based diet met the standards set by the US authorities for a “complete and balanced” diet.
“It must be remembered that animals do not need food components, but nutrients. Dogs can be vegans, vegetarians or carnivores if they consume essential nutrients in the right amounts and proportions,” says Swanson. “However, knowing the composition and nutrients is essential. Anyone can bribe their dog with vegan food, but without careful formulation you can end up with something that’s really unbalanced.”
Obese pets can benefit from a balanced vegan diet
In earlier studies, Swanson’s group showed that fresh dog food is highly digestible for humans, resulting in significantly less stool. This was not exactly the case with the vegan diet in the current study. All diets were highly digestible, but the vegan diet produced no more or less stool than the chicken diet.
“That’s not really a surprise. Because of these ingredients, it has more fiber and oligosaccharides, which could be good for dogs who need to maintain regularity,” notes Swanson.
The research team was surprised to find that some blood metabolites—chemicals in the blood that can indicate health conditions—differed between the vegan diet and the chicken-based diet. Specifically, blood triglycerides and cholesterol, which are indicators of circulating fat, were significantly lower in dogs fed a vegan diet. According to Swanson, this could benefit obese pets and help them maintain a healthy weight.
When analyzing the stool microbiome and the chemicals produced by these microbes, the team noticed other positive changes.
“There were interesting and beneficial changes in the microbial community that I believe reflected the mix of fibers that were present in the vegan diet. Phenolic and indole metabolites that contribute to fecal odor were also dramatically reduced in these diets. It will still smell, but probably less so,” adds Swanson. Overall, there appeared to be some beneficial changes in gut health in dogs fed a vegan diet.
Home Diet Warnings
The scientist says she would like to do a direct comparison between a human diet with and without meat and dairy, but for the first study to show how a fresh vegan diet works in dogs, the results are promising.
“No one has tested the digestibility of these diets in dogs before. We showed that these vegan diets led to desirable fecal characteristics, high nutrient digestibility and positive changes in some metabolites in blood and feces,” he adds. “For people who are interested in feeding their pets a vegan diet that is in line with their personal values , the diet we tested is a good choice.”
Swanson emphasizes that these diets are formulated by veterinary nutritionists and that homemade vegan dog food may not provide complete and balanced nutrition for dogs.