The most common condition with fast eating is vomiting the food soon after finishing the meal. When the stomach becomes too full too quickly, its natural tendency is to empty itself. Usually, because most dogs are indiscriminate eaters, they will just recycle the food, and by that I mean they eat their vomit. Yes, it's nasty but when you consider the dog also eats dead, necrotic carcasses and other animal's feces, it really is not that nasty.
A more serious condition associated with vigorous eating is a condition known as gastric dilation and volvulus (GDV). GDV is more common in the Great Dane, Rottweiler, Doberman Pinscher and Lab along with other large, deep chested breeds. In this condition it is believed that overeating quickly along with exercise soon after the meal will cause the stomach to rotate. When this happens the contents of the stomach are not allowed to empty and the stomach begins to increase in size. Surgical correction is the only treatment and if left untreated will end in death.
So I am often asked how one can teach a dog to eat slower? And the answer is I don't really think you can. It is the nature of the beast. I do, however, have some suggestions on how to physically slow them down. Of course one option is to just simply feed the dog several small meals throughout the day, but if any home is like mine, I simply don't have time for that. I barely feed myself and baby three times a day...much less the dog. My first suggestion to clients is to place an object in the dog's food bowl. I suggest something heavy like a moderate sized rock or a piece of a brick. This little trick causes the dog to have to "work" a little harder to get to his food. Rarely does the dog realize he can remove the object from the bowl, but in the case that he does, I have another suggestion. Feed the dog out of a muffin tin. Measure out the amount of food to feed the dog and divide it evenly among each muffin tin. This will cause the dog to have to work harder in a small hole and to have a little pause in between each cup. My last suggestion is the nifty little food puzzler. One is featured in the picture at the top. In this particular puzzle the food is kind of hidden in the grass. Another food puzzler is called the food maze and is featured below.