A study published in the journal Nature has found that dogs evolved 10 genes that allow them to digest plant-based foods and that this occurred tens of thousands of years ago. 

Like humans, they underwent genetic changes to adapt to a diet with more starch, researchers report. They say the change suggests that the rise of agriculture and the domestication of dogs might have gone hand in hand. 

The finding comes from a genome-wide analysis of differences between a group of 60 dogs and a group of 12 wolves from around the world, one of the first such searches ever done for dogs.

"Only some years ago, a study like this would have been impossible due to sequencing costs," the study author Axelsson explained. "

Co-evolution with humans

Dogs are thought to have diverged from their wolvish ancestors tens of thousands of years ago, helped along by their proximity to ancient humans. Some experts would even say that humans co-evolved with domesticated animals. Past research has shown that wild breeds such as silver foxes can be turned into docile doglike creatures over the course of just a few generations.

The international research group found 36 regions of the dog genome that showed signs of evolutionary adaptation, either because they were so different from the wolf genome, or because the genetic signature became so common among different breeds of dogs.

A large proportion of these genes were related to starch digestion and fat metabolism. Genetic variants within these genes were selected to aid adaptation from a mainly carnivorous diet to an omnivorous starch-rich diet during dog domestication.

The genetic changes enhanced a dog's ability to break down starch by secreting an enzyme known as amylase from the salivary glands and pancreas. Wolves don't secrete nearly as much amylase, and thus they don't tend to eat starchy foods.

This adaptation likely allowed dogs to become more efficient at scavenging, That is, only dogs that could make good use of the scarce and mixed leftovers survived to become the ancestors of dogs. 

This builds on an existing body of evidence that shows dogs have Type D taste buds, which are not found in obligate carnivores, and these respond to ‘‘fruity-sweet’’ compounds. Starch  is the main carbohydrate stored in plants and unlike obligate carnivores, dog saliva contains the enzyme α−amylase that is needed to digest starch. Dogs also have high glucokinase activities in their liver, similar to omnivores rather than carnivores. Glucokinase is an enzyme needed to breakdown glucose.


VonHoldt BM, Pollinger JP, Lohmueller KE et al (2010) Genomewide SNP and haplotype analyses reveal a rich history underlying dog domestication . Nature 464:898–903

Contreras-Aguilar MD, Tecles F, Martínez-Subiela1 S, Escribano D, Jesús Bernal L, Cerón JJ . (2017) Detection and measurement of alphaamylase in canine saliva and changes after an experimentally induced sympathetic BMC Veterinary Research (2017) 13:266 DOI 10 .1186/s12917-017-1191-4

 Ballard, F .J . Glucose utilization in mammalian liver . Comp . Biochem . Physiol . 1965, 14, 437–443


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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