You may have read through gritted teeth (or with joy) about a new study, published this month, that found dogs might be healthier and less prone to hazardous bacterial infections and pathogens when put on a nutritionally sound vegan diet.

Or putting it another way, compared to conventional store-bought dog foods and raw meat diets, going sensibly vegan might be your dog’s safest option.

No meat, chicken or fish in the kibble mix. No eggs or milk. Just a plant-based melange in the doggy bowl.

Could this really be the better way for our canine friends?

Are those howls of derision?

The issue of putting pets on a meat-free diet is a controversial and emotional one, for enthusiasts and critics alike.

There’s a notorious instance of a woman on Tumblr wistfully sharing photos of her dog’s tofu and sweet potato dinner.

The photos and commentary went unhappily viral, and the woman and her dog (who was mocked for looking listless) were hounded off the internet.

That occurred in 2016.

When the BBC reported the puppy pile-on four years later, it also gave a detailed analysis of the difficulties of successfully putting your cat or dog on a vegan diet.

Cats are especially tricky. They can end up dead if not fed certain amino acids, and most vets seems to believe cats will likely not thrive on plants alone.

Dogs? Maybe. And you’ll need to fork out cash for advice from a nutritionist.

The new study

In the UK study, 2596 “guardians” (dog owners) kept track of their dog’s diet, health, veterinarian visits, medication use and overall wellbeing for a year.

The study was limited to one dog per person.

Guardians were “asked to report their own opinion of their dog’s health status, and also to report what they believed their veterinarian’s assessment to be”.

Which is a bit fluffy – dog owners channelling the vet’s possible opinion.

They were also asked “to identify whether the diet was based on conventional, raw or in vitro meat, insects, fungi or algae, or whether it was a vegetarian, vegan or some ‘other’ diet”.

Respondents could select only one option. From this information, the dogs were split into three groups, according to their regular diet:

• “Conventional” meat from the supermarket pet aisle. There were  1370 of these, or 54 per cent of the participants
• Raw meat, 830 or 33 per cent
• Vegan, 336 or 13 per cent.

For each diet category, the percentage of unwell dogs and number of health disorders per unwell dog was calculated.

The findings

According to a statement from the University of Winchester, statistical analysis of the survey results suggested:

• Overall, dogs on conventional diets were less healthy than dogs on raw meat or vegan diets
• Dogs on raw meat diets appeared to be healthier than those on vegan diets.

So where does vegan is best come from?

The researchers argued against the conclusion that raw meat diets are healthier, citing three factors that we can only take at face value.

1. In the study, dogs on raw meat diets were significantly younger than dogs on vegan diets, which could help explain why they appeared to be healthier
2. Dogs on raw meat diets were less likely to be taken to a veterinarian – and while this could be seen as a sign of better health, prior research has indicated that owners of dogs on raw meat diets are less likely to seek veterinary advice
3. Prior research has linked raw meat diets to increased risk of pathogens and nutritional deficiencies.

And so they came to a new conclusion: “In light of both the new and prior findings, the researchers suggest that a nutritionally sound vegan diet may in fact be the healthiest and least hazardous choice for dogs.”

Apart from the relatively low number of dog participants being vegans, and the limitations of self-reported assessments by the human participants, it’s also worth noting that the study was funded by advocacy group ProVeg International, and that 90 per cent of the humans were female (nowhere near a representative sample).

The lead author

The lead author is Dr Andrew Knight, a dog and cat veterinarian, and professor of animal welfare and ethics at the University of Winchester.

He’s also founding director of the university’s Centre for Animal Welfare and adjunct professor in the School of Environment and Science at Griffith University, Queensland.

According to his staff profile, Professor Knight is originally from Australia, and helped launch Australia’s campaign against the live sheep trade to the Middle East in the early 1990s.

He advises: “I have tried to advocate on behalf of animals.”

His research “has explored alternatives to invasive animal use within research and teaching, plant-based and alternative companion animal diets, the impacts on climate change of animal agriculture, and the intriguing theory that Jack the Ripper may have been an abattoir worker”.

He’s reportedly a vegan but doesn’t own a dog.

He and his colleagues acknowledge that “further research is needed to confirm whether a raw meat or a vegan diet is associated with better dog health outcomes”.

The researchers suggest that large-scale, cross-sectional, and longitudinal studies of dogs, maintained on different diets, which utilises data such as results of veterinary clinical examinations and veterinary medical histories, “could yield results of greater reliability”.

See here for a short 2019 article from Veterinarian Practice News that discusses a range of issues, including dog owner thinking, that make the reality of vegan diets for dogs and cats so problematic.

It’s doable, but it’s complicated.