Roundworms (ascarids)

These are parasites which live in the small intestines and are commonly found in puppies and kittens where they cause a “pot-bellied” appearance to the abdomen commonly referred to as a “wormy belly”. Toxocara canis, Toxascaris leonine, and Toxocara cati are the important species of roundworms in dogs and cats. The eggs are periodically shed in the feces where other dogs can become infected by sniffing or licking the ground. Infected mothers can also pass the worms on to the unborn offspring through their placenta and then after birth through their milk. The infection typically causes diarrhea in young puppies and kittens, but can affect pets of any age. In cases where there is a large number of adult worms present, the pet may vomit as well. Roundworms appear in vomit or feces as long, spaghetti-like worms. Roundworm infection may also be transmitted to humans, particularly children who may not wash their hands well. Very rarely, liver problems may result from roundworm larval migration in humans (visceral larval migrans). Even less commonly, the larvae can migrate into the eye and cause blindness in humans (ocular larval migrans). Routine fecal checks should be performed to detect the parasite and monthly heartworm preventatives should be used which also prevent against roundworm infection.