Autochthonous infection of buffaloes and cattle by Fasciola hepatica in Minas Gerais, Brazil.

Fasciola hepatica is a digenetic trematode that parasitizes the bile ducts of different species of vertebrate hosts. In Brazil, this parasitosis is expanding and occurrences have been reported in the southern, southeastern, central-western and northeastern regions. This study aimed to report the first case of naturally infection of buffaloes by this parasite in the state of Minas Gerais. A total of 250 stool samples, 176 from cattle and 74 from buffaloes, from the districts of São José da Lapa and Pedro Leopoldo, were examined. Also, 402 snails of the genus Lymnaea were collected on the same farms and the viability of the eggs from naturally infected buffaloes and cattle and the susceptibility of the snails to infection were tested. A total of 54 animals were found to be positive, 33 cattle (18.75%) and 21 buffaloes (28.37%), and two molluscs showed immature forms of F. hepatica. In experimental infection of specimens of Lymnaea, cercariae were obtained through spontaneous elimination from the 57th day post-infection onwards. The importance of this first case report can be emphasized because it confirms that this parasite is being dispersed in municipalities in this state that had previously been considered to be unaffected.