USING BOARS OF CANADIAN BREEDING TO IMPROVE THE MEAT QUALITIES OF LARGE WHITE PIGS
Three experiments were carried out to improve the meat productivity of pigs of Large White (LW) breed of russian selection by different variants of crossing with the Yorkshire (Y) breed of canadian selection. There were no significant differences between the groups in terms of reproductive qualities. Two-breed pigs (LW x Y) grew more intensively and the live weight of the piglet at the 30 days was 8,7 kg, which is higher than in the other groups with a significant difference (P <0,05). When the live weight of 100 kg was reached, the вackfat thickness of the fat over 6-7 thoracic vertebrae was 26,3 mm compared to 30,7 mm in purebred pigs of the LW of the breed (P <0,001), the area of the muscular eye was respectively 45,1 cm 2 and 30,6 cm 2 (P <0,001). In the fourth generation of reproductive and absorbent crossing of pigs of LW and Y of breeds, the thickness of the fat on the carcasses of pigs was 21,2 mm (Р < 0.001), which is 30-39 % less than for the LW carcasses, the area of the muscular eye was 44 mm. In three-breed hybrids (LW x D) x L, the age of reaching 100kg was less by 12,5 days (P <0,01), the thickness of the fat was 23,6 mm, that is, it was 11,4 mm less (P < 0,001) in comparison with the control group. The replacement pigs obtained from the absorbent crossing (LW x Y) x Y showed the best results for the вackfat thickness - 19,2 mm, but they were inferior to the purebred Y (13,0 mm) (P <0,001). In the sows of this combination, 11,6 piglets were born alive, the number of piglets at weaning was 10,6, the weight of the nest in the 30-day was 78,7 kg. Differences in the frequency of occurrence of certain antigenic factors of blood in animals of different combinations of breeds are revealed. In animals that have the EAE allele edf, a higher growth rate is revealed, but thicker the backfat.