Researchers at the Western University College of Veterinary Medicine and Berkeley’s School of Public Health have shared results from a comprehensive study on the long-term impact of a plant-based diet on dog health. The study showed that a vet formulated, nutritionally complete plant-based dry food diet provides balanced nutrition to dogs in the long term. Data from the study was shared on Feb. 20 at the Western Veterinary Conference in Las Vegas.

Unlike other research on vegan diet dogs that has been criticised on the basis that it is based on owner perceptions, the data collected in this study was based on medical biomarkers of health and clinical assessments carried out by qualified veterinary surgeons. The cohort of dogs, who were monitored over a 12 month period underwent full clinical examinations and had comprehensive blood work performed at regular intervals including: complete blood counts (CBCs), blood biochemistry, cardiac biomarkers, plasma amino acids, including L-taurine, L-carnitine and serum vitamin concentrates, as well as assessments of body condition, weight, urine and faeces.

Outcome

All dogs eating a vegan diet had normal haematological parameters throughout the study and certain biomarkers of health were superior for the vegan diet dogs. In particular vitamin D levels (used to help regulate calcium and phosphorous levels) were dangerously low in 47% of participating dogs on a meat-based diet, all of whom normalised by the end of their 12 months of eating the complete vegan diet. Urine analysis showed healthy parameters in the plant-based dogs with no significant crystal production or detrimental changes. 

Heart changes 

Heart parameter monitoring was significant due to recent tenuous speculations linking grain free diets and Dilated Cardiomyopathy (DCM) in dogs. Researchers did not witness a statistically significant difference in cardiac health biomarkers when dogs were fed plant-based versus meat-based diets. The biomarkers ‘NT-ProBNP’ and ‘Cardiac Troponin I’, used to detect heart stretching and heart failure, and damage to heart muscle (myocardial damage)  respectively were both improved (lower) after 12 months on a plant-based diet, compared to after 12 months on a meat-based diet. 

Weight improvements 

Body conditions and weight scoring data showed that dogs were able to maintain a normal body weight on the vegan diet, equivalent to their meat fed counterparts. Interestingly, of the dogs in the cohort who were classified as clinically obese, 12 months on the plant-based diet normalised their body weight, possibly due to the positive impact of a plant-based diet on 'optimising hormonal regulation'. 

Pet obesity is common and a major cause of morbidity for affected individuals - any potential for vegan diets to help manage this wide scale problem would likely be of great clinical interest. 

The study was based on a cohort of 15 healthy adult dogs of different breeds ranging from ages 1 to 11, living in households within Los Angeles County, Calif. Dogs were fed different commercial, meat-based formulas for at least one year prior to enrollment of the study, and then were fed nutritionally complete vegan dry food and treats for one year. The research was conducted in an independent academic setting and was not funded by a pet food manufacturer.  

“It's common for critics of a plant-based lifestyle to discredit the growing body of evidence that shows dogs thrive on a vet-formulated vegan diet like Omni on the basis that existing studies lack clinical biomarkers and assessments. Now, thanks to this research, this argument no longer stands," Dr. Guy Sandelowsky, UK veterinarian.  

References 

Linde,A et al. (2023) ‘Domestic dogs maintain positive clinical , nutritional and haematological health outcomes when fed a commercial plant-based diet for a year’ https://www.biorxiv.org/content/10.1101/2023.02.18.525405v1 (Accessed: 28.02.2023)

AAFCO Association of American Feed Control Officials. Available at: https://www.aafco.org/ (Accessed:28.02.2023)

Panagopoulou,V et al. (2013) ‘NTproBNP: an important biomarker in cardiac diseases’ PubMed, 13(2), pp 82-94. 

Sharma,S et al. (2014) ‘Cardiac Troponins’ Journal of Clinical Pathology, 57(10) pp 1025-1026.

FAQs

But aren’t dog’s carnivores?

Dogs are in fact nutritional omnivores as demonstrated by a robust scientific study published in the reputable journal Nature (1,2) in which it was shown that they have 30 copies of the AMY2B gene responsible for digesting plant-based foods.

They have also evolved relatively long intestines (21) (almost as long as humans) and relatively flat surfaces on their molars (31, 22) which they use for digesting and chewing a whole range of foods.

The common misconception that dogs are carnivores probably arises from the fact that they are classified in the order Carnivora but so are plenty of other species like bears, skunks, racoons who are omnivores and even the giant panda who thrives on a plant-based diet (20).

Is plant protein digestible to dogs?

Absolutely yes, studies which have looked at how much protein dogs can absorb from plant-based and fungi-based foods like soya and yeast demonstrated over 75% digestibility which is on par with meat-based foods (23, 24, 34, 35 & 25).

Both these protein sources also contain all 10 essential amino acids (36, 37) that dogs need to thrive.

Isn't there too much fibre in plant-based food?

The average amount of fibre in a commercial dog food diet is between 2-4%. omni’s plant-powered recipe has a fibre content of 3% which is on par with meat- based diets.

In our survey with over 200 dog owners, 100% reported that their dog’s stool consistency was either ‘normal’ or ‘perfect’ and there were no reports of any digestive upsets (data on file).

Can I mix omni with other meat-based diets?

We are proud that our recipes are nutritionally complete and so include everything your dog needs to thrive. This means omni can be fed as a sole ration. We also fully support a 'flexitarian approach' like meat free lunches or using omni as a mixer.

Every little helps to bring some of the health and environmental benefits of plant-power to meal times. Mixing omni with meat/fish will help to add variety into your dog’s diet whilst adding in healthy ingredients with a relatively low carbon footprint.

Can plant-based food provide the essential fatty acids dogs need?

All the essential fats and oils that dogs need, including omegas 3 and 6 are found in a variety of both meat and plant-based foods (31, 28).

omni’s recipe is rich in plant-based sources of these nutrients so your dog will get all the essentials they need.

I hear a lot about feeding raw meat, isn’t that better?

Feeding raw meat to dogs has become a very popular trend in recent years, but most vets will warn against this practise. This is because the cooking process is vital to help kill off dangerous bacteria like E coli, Salmonella and Campylobacter (9) that have necessitated several food recalls from the market and caused serious illness and even death in both dogs and their owners (40, 41, & 42).

There are also several worms and parasites that are only killed off when raw meat is cooked. Dogs are dogs, not wolves and thanks to their domestication over thousands of years, thankfully don’t need to hunt to get their grub nor do they need to eat raw meat, it's just not worth the risk.

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