Immune response of sheep to Fasciola hepatica infection.

The IgG immunoglobulin levels and the immune response to Fasciola hepatica digestive tract antigens were studied in experimentally infected lambs. A synchronic increase and decrease of IgG-1 serum levels and indirect fluorescent antibody titres were observed during the course of the infection. Antibody activities were demonstrated in IgG-1, but not in IgG-2 isolates. The antibody activity was partly sensitive to reduction with mercaptoethanol.