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Tritrichomonas foetus in Cats

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Feline Tritrichomonas foetus Parasitic Infection


Cats and kittens from shelters and catteries are at higher risk of contracting an intestinal parasite that causes a long-term, foul-smelling diarrhea. The parasite, Tritrichomonas foetus (T. foetus) is a single-celled protozoan that lives in the colon of cats and is shed in the feces.


Symptoms and Types


Younger animals are most likely to have diarrhea as the result of infection. Adult cats may or may not show signs, but can still be carriers of the parasite, passing it into the environment through their feces, and putting uninfected cats at risk of acquiring it. Symptoms may not appear in an infected animal for years after being exposed.


The main symptom is a longstanding bout of loose smelly stools, sometimes mixed with blood or mucus. Cats may have difficulty passing the loose stools and strain to empty the bowels. Stool may leak out of the anus and cause redness and pain around the area.




Cats that share a litter box can pick up the organism by stepping in the litter box and then later licking its feet or fur. The organism is then carried to the colon, where it thrives. This is why animals that live in close proximity are all likely to be carrying the parasite. Cats can have symptoms that last for years and can possibly remain infected for life without ever being diagnosed.




Samples of fresh fecal matter can be examined in several ways to see if the parasite is present. Typically, the veterinarian will prefer to collect a sample during an examination, as the feces must not be mixed with cat litter or dried out.


An easy test that can be run by your veterinarian includes examination of a fecal smear under a microscope. Other test methods include culturing fecal matter; a DNA test for presence of the organism; and a tissue sample (biopsy) of the colon.



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