Young Romanov sheep are late maturing animals, and their fat appears after they reach the age of one year. To increase early maturity and intensity of body weight gain in Romanov sheep, we crossed the ewes of Romanov sheep breed with Ile-de-France rams. We carried out a scientific and economic experiment at the farm “Stepanenko” of Lomonosovsky District of the Leningrad Oblast (Gorki village). During the experiment, we studied the productivity of young purebred Romanov sheep and Ile-de-France ¾ crossbreeds. Thirty purebred Romanov first-lambers gave birth to 67 lambs; 30 Ile-de-France ¾ crossbreeds gave birth to 56 lambs. After weaning (at the age of 3 months), two experimental groups of 20 lambs each were formed. The lambs were the same age, differing only in origin. The findings showed that Ile-de-France ¾ crossbred lambs surpassed their purebred counterparts in growth rate and daily body weight gain from 3 to 7 months of age by 21.46%, in preslaughter weight by 11.14 kg, or 24.5%, in hot carcass weight by 7.06 kg, or 31.7%, in slaughter yield by 2.58 absolute percent; by 4.83 kg or 36.9% in carcass meat flesh and by 0.61 units or 15.9% in meat+fat/bone ratio. Research on this topic will continue; Ile-de-France ¾ crossbred young ewes and rams will be bred among themselves, and we will study their productivity, as well as the prolificacy of the first-lambers
Keywords
Crossbreeding, Romanov sheep, Ile-de-France, crossbreeding, prolificacy, polyestricity, meat productivity, early maturity, growth intensity