Myth: Dogs need meat in their diets.
Fact: Dogs are omnivorous (as are people), so a vegetarian diet may be acceptable. Though some strict vegetarians would argue with me, cats are born carnivorous and require high amounts of animal dietary protein, and should not be fed totally vegetarian diets.
As is true with people who prefer vegetarian diets, protein or vitamin deficiency can occur in dogs who eat strictly vegetarian diets if they are not properly supplemented. If you are concerned about dietary imbalances, you may wish to feed your dog a commercial vegetarian diet rather than prepare one at home. If you choose to prepare homemade meals, work with your veterinarian or nutritionist to properly formulate a balanced diet.
I have a number of vegetarians in my practice who do not mind their dogs eating meat or animal-based products. In the wild, dogs prefer animal-based protein. I think it’s important that they eat the diet most closely resembling what they would eat if hunting on their own. Nevertheless, I respect your dietary choice and would not have a problem advising you to feed your dog a vegetarian diet (even though he would most likely prefer a diet that contains some amount of animal-based protein), as long as you heed my cautions about doing so. If you choose to purchase a natural diet for your dog, make sure it’s free of animal and plant byproducts, and chemicals such as BHT, BHA, and ethoxyquin.