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Internal Parasites

The most common types of internal parasites in your pets are roundworms, tapeworms, hookworms, and whipworms. These internal parasites typically live in the intestinal tract of puppies and kittens, but infection can occur in adult dogs and cats of all ages, if opportunities exist for exposure. Diarrhea, vomiting, weight loss, anemia, and a poor hair coat can all be clinical signs associated with an intestinal parasite infection in your pet.


At Claremont Animal Hospital, we recommend a yearly fecal screening for intestinal parasites and a monthly deworming preventative (which is usually in combination with a heartworm preventative). Call us today to choose a flea/tick/heartworm/deworming preventative appropriate for your pet!



Roundworms are common intestinal parasites found in dogs and cats. Puppies and kittens can be infected by their mother. Growth can be affected in a growing animal infected with these organisms. A characteristic 'pot bellied' appearance can be seen in infected puppies and kittens. Roundworms are very easily transmitted from infective eggs shed in animal fecces. This makes it important to clean feces quickly once excreted to prevent contamination and spread of these organisms in your outdoor spaces.



Hookworm infection occurs by ingestion of larvae from contaminated environments. Hookworms attach to the intestinal lining of your pet and feed by sucking blood. Because of this feeding method, hookworms can cause severe anemia, often seen as excessive tiredness, especially in small animals. Adult worms live in a pet's small intestine then deposit eggs that are passed into the stool to develop into larvae and continue the cycle.



The whipworm is an intestinal parasite found most commonly in dogs. Adult worms live in the large intestine and pass eggs into the stool. Infection occurs when eggs are ingested from a contaminated environment.



The tapeworm is a segmented parasite found in many mammals. Each tapeworm segment contains eggs that are passed into the stool to continue its infective cycle. The tapeworm head stays attached to the intestine to continually produce new segments for shedding purposes. Infection in your pet occurs ingesting an intermediate host such as an infected flea or infected wild prey (including rodents and rabbits). Pets will continually become reinfected with tapeworms if these intermediate hosts are not controlled in and around your home.