Some people thrive on a vegan or vegetarian diet and insist that their dogs will, too. The other debate that by declining the dogs from meat, these owners are performing cruelty against an animal. Each of these sides has their legit reasons, but what does science say about this issue?
This article is going to dig in the biology of dogs in comparison with other animals, including human, to find out if a diet free from meat will benefit them or not. To find out what are dogs’ nutritional needs, we can take a look at their anatomy and find out what kind of diet is it adapted into.
It has been 10,000 years since a man domesticated a dog. We even call them “man’s best friend”, so it’s no wonder that humanizing dog is on the trend. We give them clothes, we groom them in salons, we flock our houses with their beddings, crates and toys. A dog is no less than a member of the family. This is even more true in the first world countries. There are approximately 73 million household dogs in the U.S, which nearly double its number of households, which is about 43 million. This is just the registered number, so we assume that the real number of dogs in the United States is much higher.
Anatomy of Dogs
As many people have considered their dogs as one of our race, the fact is still that we are not really close to them, biologically. As for genes, dogs share the most similarity with gray wolves with 99% of mitochondrial DNA alike. This discovery has made the Smithsonian Institution reconsider today dogs’ origin. Now, they are in the Canis lupus familiaris classification, which includes the Timber wolf and other gray wolves.
Wolves are evolved as carnivores, their anatomies only support meat-based diets. The same also applies for dogs and cats. This classification and analysis of their anatomy help us understand which food fits their body structure the best.
According to “Theory and Applied Genetics” by Robert Wayne Ph.D., animals can be divided into three categories, based on their anatomical and physiological structure. Each category is evolved to eat some certain kinds of food. Right now, we have three categories, which is shown below:
Eat Both Plant and Meat
|Sheep – Cows||Bears – Human||Dogs – Cats|
|Long Digestive Tract – break food down easily||Medium Length Digestive Tract – digest plants and animal protein flexibly||Short & Acidic Digestive Tract – because proteins and fat from animal are absorbed easily, this feature is not elaborated|
|Molars Square and Flat – grind and break plants||Square Molars – grind & Sharp Teeth – tear food||Sharp Teeth – Tear Flesh and Kill Prey|
|Pronounced Lower Jaw – move sideways to chew plants||Jaws Move Vertically – cutting motion to eat large chunks of meat|
|Enzymes For Digesting Carbohydrates||Enzymes for digesting carbohydrates – digest starch||Low gastric pH – facilitate protein and kill bacteria
No Amylase – Hard to digest carbohydrates
With the key anatomical features above, we can partly conclude that dogs and cats would thrive better on a diet based on meat. With domestication, the appearance of this species has changed greatly, but their inside organs did not change much. Dogs are able to eat like their ancestors do, in fact, they need all those animal proteins and fats to reach optimal health. Dogs and cats can indeed eat carbohydrates in plants and grains, but they will not digest them fully and will not meet the nutritional requirements from plant-based proteins.
Are Plant Proteins Good for Dogs?
Not all proteins are made the same, and the main feature that differentiating them is the amino acids content. Plant proteins lack some of the amino acids that dogs and cats need, like arginine, taurine, methionine, lysine, and tryptophan.
On the other hand, plant proteins are hard to be broken down, therefore it would take a lot of time for dogs to digest the protein from plants, while all of the nutrients would be push out because they cannot be absorbed. Animal based proteins have higher digestibility level.
Fat In A Dog’s Diet
Unlike a human, dogs as carnivores will not suffer from cholesterol problems if they eat a lot of animal fats. In fact, they need those fat to provide more energy and the essential fatty acids, which they can’t produce by themselves. Carbohydrates and fats both provide energy, but the way they function inside a dog’s body is different. As a dog relies on carbohydrates for energy, he will have excess lactic acid in his muscles, which will lead to weakness and fatigue.
Another important thing that fat does for dogs is providing them with Omega-3. Plants have ALA as omega-3m which can be found in soy, canola oil or flax. These are omega-3 in short chain, which is ineffective in a dog’s body. Meanwhile, fish has DHA and EPA as omega-3, which is in a long chain form and is readily absorbed in a dog’s body.
From the features of different anatomies, we know that humans and dogs are evolved differently: each will thrive on a different kind of diet. Dogs can exist on an exclusively plant-based diet, but the micronutrients they need will not be provided that way, and they cannot reach optimal health.