Fascioliasis in beef cattle in north-west Argentina.

Two thousand and ninety beef cattle livers from north-west Argentina were inspected at a large slaughterhouse in Salta; 13% were found to have lesions of fascioliasis and these were classified according to their severity. Of the livers condemned 182 (67.2%) were lightly affected, 77 (28.4%) moderately affected and only 12 (4.4%) severely affected. In a field survey 85 animals, mainly between 6 and 18 months old, were slaughtered and 12 (14%) had lesions of fascioliasis. The influence of Fasciola hepatica on weight gain in beef cattle was assessed on 2 farms. Infected animals were divided into 2 groups and I group was treated monthly. Only on 1 farm were the animals exposed continuously to infection. No differences in weight gain were found over 7 and 14 months respectively when compared to untreated controls. It was concluded that fascioliasis is widespread but at a low level in beef cattle.