Whipworms are nasty parasites that can that can live in a dog’s large intestine and feed on his blood.  Some dogs with whipworm show no symptoms at all but many have diaherrea and lose weight. In severe cases, the they may develop anemia. Because infected whipworm eggs are passed in an infected animal’s feces,   they can contaminate water and soil. Healthy dogs then contract whipworm by ingesting the eggs.  To prevent problems, keep your yard free of droppings and bring a fecal sample in when you take your dog for is routine examination. Your veterinarian will perform a fecal test to check for whipworm. He will prescribe a pet medication like a canine de-wormer if the test is positive.