Earlier this year, I was involved in a back and forth discussion with a Professor of nutrition (at 2 universities; Murdoch in Australia, and Winchester in the UK) in the Vet Times about the feeding of vegan pet foods to our carnivorous pet cats and dogs.
It saddens and frustrates me to see the level of ignorance and insanity within the veterinary profession from the highest level of education down to clinicians at the coalface of veterinary practice who I see have put their names to a vegan brand of pet food. I don't care if people choose to be idiots, but I do care that due to the willful ignorance of a few empty vessels and the spineless refusal to stand up and call them out by the majority, their loud utterances will result in the suffering of pet dogs and cats. Their owners too, who are no doubt acting in good faith, will suffer the emotional trauma of the illness they see and the cost of treatment, but who must also bear some responsibility for failing to educate themselves properly.
I would probably not have bothered to publish the extended conversation, but the Vet Times saw fit to unilaterally edit one of my letters as you will notice below when you read my comment on it. They also failed to publish my last response, and I hate the idea that the Prof had the last word without pulling him up on his mistakes.
It starts off with the article that was published in Vet Times that triggered my first letter...
Enjoy!
My first letter in response to the above article...
My letter received the following responses... the first on 04/02/2025
and then from Prof Andrew Knight on 11/02/25...
... joined by Jolanda Hill in the same edition of Vet Times too, who clearly has no idea about the evolution of either dogs or humans nor the diets they consumed during their respective evolution...
My friend and colleague, Tom Lonsdale interjected his wisdom on 25.02.25 as follows...
My reply, although promptly sent in, was published the following week on the 04/03/25. Clearly the Vet Times were happy to spin the verbal jousting out and fill in column inches with minimal effort on their part...
...or so I thought until I read what had been printed a bit closer.
The Vet Times had seen fit to edit my letter above by removing the scientific qualifications of the scientists I had named in my submission. What I'd actually written was the following...
There are a number of scientists he might like to check out too such as Prof William Happer, Dr Ian Plimer, Dr Judith Curry, Dr Steve Koonin and many others who are suppressed and censored for daring to provide the true evidence on what is actually happening to our climate rather than some poor model used to justify the scaremongering and resulting politics. [Bold added here to highlight what was deliberately removed.]
and later on
Check out the work of Laszlo G. Boros MD on deutenomics5. He could start with looking at Dr Anthony Chaffee’s excellent YouTube channel and his video on the inherent toxicity of plants commonly consumed as foods6.
These weren't typo omissions. The Vet Times had deliberately and knowingly disrespected these scientists and their professional achievements as an attempt to undermine the validity of my arguments and points, and to portray me as someone who didn't follow scientists and/or scientific knowledge. I was not best amused as you might imagine, but I see it as recognition that they thought Prof Knight needed their intervention because without such interference they must have felt that he was losing the argument.
Prof Knight's response was published on 18/03/2025 ...
And there the discussion in Vet Times ended, without further publication.
As you might imagine, I hadn't let it lie at that point, and had submitted the following reply....
It would appear that the Vet Times weren't prepared to publicise Prof Knight being admonished and put in his place, although I think his students have the right to see it given the misinformation I have no doubt they are being fed by him.
Dear Editor
In line with Andrew Knight’s request on 18th March 2025 for further education, it would be rude of me not to comply. He can jot it down as CPD, although I’m not quite sure why Andrew Knight is thanking me for educating him when he clearly hasn’t bothered to check out the substance of any of the references, or the professors and those with PhD’s that I recommended? Maybe he did but failed to comprehend what he read in line with his self-diagnosed diet-induced affliction. Who am I to disagree with him on that?
He has no grounds, other than his own bias and refusal to check out the science that I have presented, to assert that my position has no scientific basis, notwithstanding the proof from millions of years that all species do best on the diet they ate during their evolution. He has addressed none of the specific points I have raised including the most basic ones that dogs are not adapted anatomically or physiologically to a vegan diet. He has failed to justify the rationale for including harmful plant-based anti-nutrients, the inability of a vegan diet to provide all essential nutrients present in the RMB diet, the inability of synthetic additives to replace their natural nutrient equivalent, or deutenomics.
Andrew relies almost entirely on his own studies for reference which demonstrate his clear bias towards vegan diets for carnivores. I shouldn’t have to inform a Professor that marking your own homework doesn’t belong in a proper scientific discussion.
Once again, Andrew demonstrates his lack of nutrition knowledge beyond anything vegan, although I question the nutritional understanding of anybody advocating a vegan diet for carnivores in the first place. My challenge to him was to put a vegan diet up against a raw meaty bones (RMB) diet, which is not the same as a “raw meat” diet. I would have thought a nutritionist would recognise the difference.
For Andrew to quote the Dodds paper from 2022 he must have been really scraping the barrel, although Dodds at least acknowledges that dogs are carnivores. To recognise that plant-based diets have nutritional deficiencies but dismiss them because disease linked to them has not yet been reported has to be one of the most ridiculous statements I’ve ever read on this subject. Deficiencies by definition will lead to disease or else they aren’t deficiencies. That they have yet to be reported in the published literature does not preclude that fact. It simply confirms the current unscientific plant-based bias. “Meat-based diet” includes anything from kibble to RMB so is not the comparison suggested by Andrew’s letter. Owner perception is not an objective measurement by any stretch of the imagination, and is totally open to the sort of bias that Andrew is personifying by the owners who were feeding a plant-based diet. The authors acknowledged pet food manufacturer influence too. This paper and any conclusions it draws must be disregarded from our debate on the basis of the above.
Having quoted it in his letter, Andrew failed to provide a reference for his own 2022 paper, if it in fact exists?! Another brain failure Andrew? His own study from 2024 was once again an analysis of data from an owner survey, so can only be regarded as poor quality evidence at best with a variety of highly significant limitations.
There are all sorts of reasons why people choose a certain diet to feed their dog which could explain the reported results with regards to health. I expect most people who feed a vegan diet are doing so for ideological reasons and have probably been doing so since they first brought their dog home, whereas many people switch to feeding a raw meat diet because their dog had ill health on a “conventional meat” (kibble/tinned) diet. With such a young age of dogs surveyed, the ill health that results from a vegan diet won’t necessarily have fully manifested, or aetiology recognised. Sometimes, especially if the raw meat diet is being fed incorrectly, as many are, it can take a while for the original health issue that initiated the switch to resolve. In some cases, for this reason there may only ever be partial improvement rather than full resolution which is sufficient reason to remain with the raw meat diet, but the original health issue might still require veterinary help albeit far less frequently. Few will be feeding the proper RMB diet that fully satisfies the physical requirement of the diet and naturally keeps the teeth clean and the gums healthy, and without fruit or vegetables in line with my previous dare. The fact that the “raw meat” diet group had a higher dental disease incidence than the vegan diet group confirms this. The low dental disease figure of the vegan group when there is no way that a vegan diet can prevent periodontal disease suggests that the vegan owners were grossly under-reporting problems too, probably in order to support their chosen feeding ideology given the fact that the vast majority of veterinary surgeons correctly consider a vegan diet to be totally inappropriate. This paper is completely unreliable on the basis of the above.
With regards to the reported increased pathogenic risk from raw meat diets, that is largely dependent on the source of the raw meat and how it is processed, stored and fed. All that tells us is that RMB should be properly sourced, stored and fed. There is no need for any processing beyond portioning it into large lumps of RMB where appropriate. Given how many people feed raw meat diets on a daily basis without any problems from doing so for many years as I have done myself, this issue is blown way out of proportion – a bit like anthropomorphic climate change. On the subject of which, repeating the greenhouse myth doesn’t make it fact.
Whilst I don’t have a PhD or professorship, knowledge isn’t exclusive to those who do. Indeed, as Andrew is demonstrating, their knowledge is often confined within such narrow limits as to be impractical and irrelevant in the wider world. As I have discovered during my own exploration of the subject, there is far more to nutrition than what is taught on veterinary courses and discussed in the published papers that Andrew Knight supplies and relies upon. His assertion that the evidence is overwhelmingly in favour of vegan diets is only true if you ignore the much larger body of evidence that it isn’t! Cherry-picking weak data to suit his agenda doesn’t alter this fact. Unfortunately, my concerns regarding veterinary education with regards to carnivore nutrition have been significantly more stoked than abated.
Yours faithfully
Roger S. Meacock BVSc MRCVS
References:
Previous VT correspondence within this thread.
Dodd S. et al (2022). Owner perception of health of North American dogs fed met- or plant-based diets. Res. Vet. Sci. 149: 36-46.
Knight A. et al (2024). Vegan versus meta-based dog food: guardian-reported health outcomes in 2,536 dogs after controlling for canine demographic factors. Heliyon 10(17): e35578