Estudos experimentais com Lymnaea cubensis Pfeiffer, 1839 (Mollusca, Gastropoda, Basommatophora, Lymnaeidae), como hospedeiro intermediário de Fasciola hepatica L., 1758 (Trematoda, Fasciolidae), no Estado do Rio de Janeiro

Abstract

Starting with Lymnaea cubensis Pfeiffer, 1839 collected in valleys in the municipality of Três Rios, Rio de Janeiro State, generations of this species were reared in the laboratory, permitting studies on oviposition, hatchbility, resistence to dessecation, and sexual maturation; additionall y the susceptibility and resistance to infection with the miracidium of Fasciola hepatica, L., 1758, and the development of this trematod e in the mollusc were studied. The role o f L. cubensis as an intermediate host for F. hepatica was established in laboratory experiments. The grester susceptibility of this species to the miracidium of F. hepatica, was observed, together with the emergence of a smaller number of cercariae whan compare d to Lymnaea columella Say, 1817, also an intermediate host of this trematode in Rio de Janeiro State. Experimentally, the prepatent periods for F. hepatica, in various host, were found to be: bovine, 71 days; rabbit, 65 days; rat, 41 - 44 days; hamster, 33 - 34 days, and mouse, 32 - 35 days. In the guinea-pig, adul t F. hepatica were observed 56 days post infection, with ova in the uterus. 44 A prevalance of 35,8% for fasciolosis was noted in 475 cattle examined in the municipality of Três Rios.