Ingestion of Fasciola gigantica metacercariae by the intermediate host snail, Lymnaea ollula, and infectivity of discharged metacercariae.

The rate of ingestion of Fasciola normal metacercariae (NMc) encysted on plants by Lymnaea ollula was examined, and the infectivity of the ingested metacercariae (IMc) in the feces of the host snail to mice was studied. As a result of ingestion by snails, the metacercarial outer cyst disappeared in about 50% of IMc in feces. There was no significant difference in the liver juvenile recovery at autopsy between mice inoculated with NMc and IMc kinds of metacercariae. Compared with NMc, the number of IMc could more easily be counted, because the separation of IMc from fecal contents under a microscope was not laborious.

Prevalência de Paramphistomum no rúmen e retículo de bovinos no Estado do Rio Grande do Sul - Brasil / Prevalence of Paramphistomum in the bovine stomach and reticulum in the State of Rio Grande do Sul - Brazil

Estudou-se a prevalência de trematódeos no rúmen e retículo de 2.202 bovinos provenientes de 24 municípios do Estado do Rio Grande do Sul, através de necropsias efetuadas em matadouro. Constatou-se que 21 dos municípios estudados estavam positivos para Paramphistomum spp. e 26,3% dos rumens e retículos parasitados com o helminto. A prevalência deste trematódeo foi maior nos municípios de Santa Vitória do Palmar (100%); Capão do Leão (97,6%) e Palmares (90%).

The prevalence of stomach and reticulum flukes was observed in 2.202 cattle from 24 counties located in state of Rio Grande do Sul state, Brazil, through necropsies at slaughterhouse. It has been found that 21 counties were positive for Paramphistomum spp. and 26.3% of stomachs-reticulum were parasited with the helminth. The prevalence of the flukes was higher in Santa Vitória do Palmar (100%); Capão do Leão (96.7%) and Palmares (90%).