Odrobaczanie danieli Fenbesanem w hodowli fermowej

Post mortem examination of 8 fallow deer before and 7 after deworming with Fenbesan in dose 7.5 mg/kg body weight during three following days administrated per os, showed unaequal sensibility of different species of gastrointestinal nematodes on this medicament. Especialy resistant to this drug were nematodes Ostertagia drozdzi and O. leptospicularis, and their percentage index of invasion intensity increased considerably after deworming. It can be a beginning of drug resistance. It is necessary to use different drugs to avoid it.