Productivity and resistance of sheep depending on the grazing period duration

Abstract The purpose of the research is to establish the productive qualities and resistance of the sheep organism at different periods of keeping sheep on pastures. Studies on improving the pasture use system were carried out on three groups of sheep with the beginning of the pasture season on April 25: Group I – with the end of the pasture season on October 15, II – on November 15, and III – on December 15. The data obtained indicate that the females kept on pastures for a longer time exceeded their peers of other groups by 1.6-2.0 kg in live weight. Before being driven to pastures on April 20, their live weight also turned out to be higher by 0.8-1.2 kg, and during their stay on pastures – by 0.7-1.6 kg, which indicates the expediency of longer grazing of sheep. In terms of live weight, the superiority of late weaning compared to the average was 1.25%, over group I (early term) – 5.23% (P>0.95). The blood of young ewes with a long grazing period contained more leukocytes, gamma globulins, erythrocytes and, most importantly, hemoglobin.