Abstract
Activated oncospheres of Taenia ovis were incubated for 24 h or 48 h at 37.5°C in Medium 858 alone or in Medium 858 enriched with 20% lamb serum or foetal calf serum. Antigens contained in the supernatant medium from these incubations were concentrated, emulsified in Freund's incomplete adjuvant and injected intramuscularly into lambs. These lambs developed a very high level of immunity to subsequent challenge infection with T. ovis eggs.