EN
The observations were performed on 51 cows from 3 cowsheds in a large scale farming. The animals were divided into three groups. Group I — 17 animals which were given three times at 6—7 days intervals before the term nitrogranulogen intramuscularly at a dose of 2.0 g/kg of bw in 20 ml of physiological salt saline. Group II — 17 animals injected intramuscularly levamisole at a dose of 2.0 ml/kg bw three times at 6—7 days intervals before the term. Group III — 17 non treated animals served as a control. It was found that in group I a percent of postpuerperal disturbances was the lowest (17.65%), in group II 23.5% and in group III 35.3% of disturbances were noted. Also duration of a service period was the most convenient in group I and II, 87.58 and 89.47 days, respectively comparing to controls — 102.94 days. In the experimental cows the index of pregnancy was lower than that in control animals. Newborns from cows treated with nitrogranulogen or levamisole were stronger, incidence of diarrhoe in these calves was lower, body weight gains were higher comparing to progeny of control cows.