PRODUCTIVE CHARACTERISTICS OF CROSSBRED YOUNG SHEEP OB-TAINED FROM CROSSING OF NATIONAL BREEDS WITH RAMS OF MEAT BREEDS OF FOREIGN SELECTIVE BREEDING

Abstract

The article presents the results of comparative study of some productive indicators of purebred and crossbred offspring obtained from insemination of sheep of national selection (Dzhalgin merino, (DzhM), Russian meat merino (RMM) with rams of foreign selection (Charollais, (Сh), Ile de France (IDF)). The data on the level and quality of sperm production of rams, main reproductive parameters of sheep, dynamics of live weight of purebred and crossbred young stock from birth to 8 months of age are presented. It is stated that the main quality parameters of semen production (volume, mobility and concentration) were not significantly different between rams of different breeds. Certain differences were observed in key reproduction parameters (fertilisation rate, gestation period, ease of delivery and fecundity), but the results were significantly different for the parameter “ease of delivery” in the ewes, which were inseminated with Charollais rams. At birth, the crossbred lambs exceeded the live weight of the offspring of purebred DzhM rams by 13,9 and 11,6%, and the offspring of purebred RMM stud rams by 6,8 and 9,1%, respectively. The discovered pattern in live weight between the compared variants was preserved at 2 and 4 months of age. By 8 months of age, the crossbreds of DzhM x IDF exceeded the live weight of the purebred offspring of DzhM rams by 8,1 kg, and the crossbreds of DzhM x Сh by 6,2 kg. The same advantage at 8 months was discovered in the crossbreds of RMM x IDF and RMM x Сh, whose body weight was greater than their purebred RMM herdmates by 3,6 and 3,2 kg. Thus, the crossbred young animals had significant advantages in body weight at all age periods from birth to 8 months of age.