EN
The study were carried out on 90 breed dairy cows chosen at random and divided into two groups: the control one (K) and the experimental one (D). The animals from the experimental group were injected with immunostimulative doses of 10% levamisole (2,5 mg/kg of body weight) three times before delivery in weekly intervals during a 2-year period from 1991 to 1993. The extensiveness of gastro-intestinal nematodes invasion in all experimental and control cows was investigated by the coproscopic method during the period from October 1992 to September 1993. The extensiveness of invasion was 56% in the experimental group, about 33% lower than in the control group. This difference was unchanged during the whole period of the investigation independently of the observed seasonal changes of gastro-intestinal nematodes invasion in each group.