Puppies are often born with them and can be treated as early as three weeks. In puppies, the larvae penetrate the small intestine and then enter the bloodstream to arrive at the liver and lungs. Sometimes, they will even travel up the trachea where they can be coughed up, swallowed then pass back to the intestines where they mature and reproduce. These worms can also migrate to the muscles where they form cysts and lie dormant. If the dog becomes pregnant, the worms can migrate to the lungs of the developing puppies as well as into the mother s milk.
Hookworms actually attach themselves to the dog s intestinal wall.
When untreated, they can cause intestinal bleeding, bloody diarrhea, anemia and even death. Whipworms are often the hardest to cure in dogs because of the prolific nature of the female worm. One female can produce in excess of 2,000 eggs a day, these eggs are passed in the dog s feces and can survive in the soil for years regardless of the cold or heat of a given region. Tapeworms occur when a dog bites and swallows fleas. They are made up of many flat segments that resemble moving grains of rice.