The Green Green Grass of Home Dogs are not known for being fussy eaters.  Put it in your dog’s path and he’ll gobble it up, whether it is table scraps, garbage….. or grass.  Although dogs like to eat meat, they can survive on a well-balanced vegetarian diet.  Cats, on the other hand, could die without animal protein.  No one is sure why your pup likes grass, although there have been many theories offered.  Primarily, dogs are descended from wild canids (wolves), which ate the entire “kill” when they hunted for food.  Since they ate many plant-eating animals they ended up eating a lot of plants and even berries found in the stomach and intestines.   Interestingly, carnivores tend to go for the stomach and its contents first, so it’s likely that dogs may eat grass because they like it and it was once part of their normal diet. Most veterinarians believe that dogs eat grass simply because they like it and vomiting just naturally follows.  When dogs eat grass, the grass acts as an irritant and causes vomiting.  However, they probably don’t know to use grass as a medicine when they have an upset stomach.  Some veterinarians believe that dogs eat grass because their prepared diets are lacking in greens and so they eat grass.  Often they seek out a particular variety of grass to nibble. No matter what the reason, your dog’s “grass” habit is normal behavior.  Take care that your pet does not eat grass that has been treated with fertilizer, pesticides or herbicides.  These could cause stomach upset or even worse problems for your dog.