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Cat Parasites

cat_vetWorms, or intestinal parasites, can affect all kittens and cats. Intestinal parasitism is one of the most common conditions in clinical veterinary practice and is frequently identified in outdoor cats.

Types of Intestinal Parasites in Cats

Many types of parasites infect cats. The most common feline intestinal parasites in the United States are roundworms (Toxocara cati or Toxascaris leonina) and tapeworms (Taenia taeniaeformis, Dipylidium caninum, Echinococcus multilocularis) followed by hookworms (Ancylostoma tubaeforme, Ancylostoma braziliense). Some intestinal parasites can infect kittens through lactation from an infected mother, and this is why it is important to treat kittens with de-worming medications throughout kittenhood.

How Are Cats Infected with Intestinal Parasites?

In addition to the potential of being infected through the mother, cats can become infected with roundworms and hookworms through ingestion of eggs or larvae from soil or the environment and by ingestion of infected prey animals such as mice and squirrels. Cats can become infected with tapeworms through ingestion of proglottids (infectious tapeworm segments full of eggs that look like pieces of rice) or by eating the intestines or tissues of prey animals. Cats may also ingest infected fleas and become infected, and all cats with tapeworms should be carefully examined for the presence of fleas.

Clinical Signs of Feline Intestinal Parasites

Infected cats can show signs such as vomiting, diarrhea, lethargy, weight loss, anemia (low red blood cell counts), respiratory signs (breathing problems, cough) and an enlarged belly. Some cats may never show symptoms of infection, while others can become very ill. Owners may see worms or proglottids passed in the vomitus or stool or emerging from the anus. Some cats will exhibit itching in the anal area and drag their rear quarters against rugs and carpets.

Diagnosis of Intestinal Parasites in Cats

Intestinal parasites can also be diagnosed by identification of eggs in a fecal sample. This is why your veterinarian requests a yearly fecal sample for evaluation.

Treatment of Intestinal Parasites in Cats

Several medications are available which effectively treat these feline parasites. Treatment usually includes a single treatment followed by several follow-up treatments to kill all immature worms in the body. There are many different de-worming medications available throughout the United States (pyrantel pamoate, fenbendazole, praziquantel). Each medication treats different worm(s). It is, therefore, imperative that you immediately contact your veterinarian if you suspect that your cat has worms. The veterinarian will identify the worm species and prescribe appropriate treatment. Over-the-counter de-wormers are usually not helpful.

Prevention of Feline Intestinal Parasites

The best way to decrease the likelihood of intestinal parasites in your cat is to keep him indoors. All outdoor cats should undergo regular de-worming with medicines that will kill a variety of parasites and should be treated with flea preventatives, all available from your veterinarian. Some of these parasites can infect humans, and this is another reason to emphasize parasite prevention, particularly in families with young children and immune-compromised family members.

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