EN
Thirteen strains of C. perfringens D were isolated from dead Iambs (age 1—8 months) in 7 outbreaks of enterotoxaemia. The most virulent isolate C 87—88 producing epsilon toxin at a titre 512 DLM₁₀₀/ml was used to produce an autovaccine Perfrinvac D. The autovaccine injected once induced in pregnant sheep a high level of antitoxic antibodies (mostly more than 64 antitoxic units/ml), easily transferred via colostrum (generally more than 32 au/ml) to lambs (in 4 weeks old lambs a titre of antibodies reached 31—64 au/ml). In outbreaks of enzootic form of enterotoxaemia this titre protected lambs completely against disease.