ORAL-TRANSMISSION OF TRYPANOSOMES OF THE SUBGENUS HERPETOSOMA FROM SMALL MAMMALS

The rodents Microtus agrestis, Clethrionomys glareolus, Apodemus sylva ticus and white BK rats were given either a single intraperitoneal (i. p.) injection, an intragastric (i.g.) inoculation or an oral (p.o.) in oculation of the culture forms, including metacyclic trypomastigotes, of Trypanosoma microti, T. evotomys, T. grosi and T. lewisi, respectiv ely. Similar levels of parasitaemia were produced by each of the three routes of infection, although the prepatent period was 3-5 days short er in the case of the i.p.-injected animals. The oral inoculation of b lood from mice infected with T. musculi into uninfected mice (outbred) and from rats infected with T. lewisi into uninfected BK rats produce d parasitaemia after 6-8 days. This is the first report of the oral an d i.g. transmission of T. microti, T. evotomys and T. grosi into their specific homologous hosts.