The Experimental Infection of Amphibia with Cultures of Trichomonas

Abstract

1. Cysts of Trichomonas batrachorum have never been found in repeated examinations of faeces nor of cultures made from them from Bufo vulgaris and Rana temporaria.2. In dilutions of cultures in rain water with large surfaces exposed to the air Trichomonas batrachorum dies in forty-eight hours; but in long columns of water and absence of oxygen they live, in some cases, for months.3. T. batrachorum will not live at 37° C., and T. hominis, though it lives at room temperature, will not multiply.4. Tadpoles of Rana temporaria and Bufo vulgaris and larvae of Salamandra maculosa have been reared free from Protozoa.5. Tadpoles of all three species of Amphibia have been infected with Trichomonas by feeding them on cultures free from cysts.6. Tadpoles of Rana temporaria can be infected with Trichomonas batrachorum isolated from Bufo vulgaris, and tadpoles of B. vulgaris with Trichomonas from Rana temporaria. It is concluded therefore that Trichomonas batrachorum in frogs and toads is one true species.7. Trichomonas sp. isolated from Lacerta viridis will not infect tadpoles of Bufo vulgaris and Rana temporaria.8. Cultures of Trichomonas batrachorum from Bufo vulgaris will infect larvae of Salamandra maculosa though this species of Trichomonas has not been described from this amphibian.