Pentatrichomonas hominis (Davaine, 1860) Wenrich, 1931

(Figure 1-26)

Trichomonads have been described from the large intestine of cats (Wenrich, 1944). The species in the intestine of the cat is not the same as that found in the mouth of the cat and other animals. The parasite from the intestine of the cat has been considered a separate species by some authors (Brumpt, 1925; Cunha and Muniz, 1922); however, others have felt that it is the same species found in man and other animals ,such as the dog. The organism in the feces of humans has been shown capable of infecting cats that are orally inoculated with trophozoites (Kessel, 1926; Hegner & Eskridge, 1935). Reports of trichomoniasis from cats have been reported from the United States (Jordan, 1956; Hegner & Eskridge, 1935, Hitchcock, 1953; Visco et al., 1978), Europe (Brumpt, 1925; Simic, 1932; Wagner and Hees, 1935), South America (da Cunha and Muniz, 1922), and China (Kessel, 1926 & 1928). It does not appear that this organism causes disease in the cat, rather being a commensal that is found in feces of cats with diarrhea due to other causes.


Brumpt E. 1925. Recherches morphologiques et expérimentales sur le Trichomonasfelis da Cunha et Muniz, 1922, parasite du chat et du chien. Ann Parasitol Hum Comp 3:239-251.

Cunha AM, Muniz J. 1922. Sobre un flagellado parasito do gato Brasil-Medico 1:285-286

Hegner R, Eskridge L. 1935. Absence of pathogenicity in cats infected with Trichomonas felis from cats and Trichomonas hominis from man. Am J Hyg 22:322-325.

Kessel JF. 1926. Trichomoniasis in kittens. Proc Soc Exp Biol Med 24: 200-202

Kessel JF. 1928. Trichomoniasis in kittens. Trans R Soc Trop Med Hyg 22:61-80.

Jordan HE. 1956. Trichomoniasis spp. in feline: A case report. Vet Med 51:23-24.

Simic T. 1932. Étude biologique et expérimentale du Trichomonasintestinalis, infectant spontanément l’homme, le chat et le chien. Ann Parasitol Hum Comp 10:209-224.

Wagner O, Hees E. 1935. Der kulturelle Nachweis von Trichomonas vaginalis und anderen Trichomonasarten. Zntralb Bakteriol 135:310-317.

Wenrich DH. 1944. Morphology of the intestinal trichomond flagellates in man and of similar forms in monkeys, cats, dogs, and rats. J Morphol 74:189-211

FIGURE 1-26.Pentatrichomonashominis trophozoite in human feces. The organism was fixed then stained with iron hematoxylin and photographed using phase microscopy. The large nucleus of the trohozoite and the undulating membrane can be seen in this photomicrograph.