Iraqi Journal of Veterinary Sciences

Abstract

The authors investigated the influence of TG5 and LEP gene polymorphism on quantitative and qualitative meat composition of 20 month old bull calves of the Hereford (n=38) and Limousine (n=26) breeds, which were bred in the climate of Cis-Ural steppe zone from 2013 to 2015. The Hereford calves were the offspring of the cattle from the southeastern states of Australia and Tasmania (3rd descent of the main lines: Baz-Gol-Sol 2U 6827, Domino 325676, Ardmors-Domino 56, Silverlend 31432); the Limousine calves were the descendants of the offspring resulting from the accumulation cross breeding of Simmental cattle with the French Reproductive Recognized bulls (4th descent of the Reper 433 and other lines). The analysis of TG5 genotype frequency in the examined populations reveals that the animals have significant (P<0.01 or P<0.05) potential for increased taste and nutritional qualities of beef associated with a high proportion of desirable TT genotype, probably related to the foreign origin of the cattle. There were no carriers of the BB genotype of LEP genes in the examined populations. Significant (P<0.01 or P<0.05) dependence between the studied SNP in TG5 and the rates of total body fat, the proportion of adipose tissue in the morphological carcass composition (or meat composition), and the content of intramuscular fat in the longissimus, as well as the correlation between the studied SNP in LEP and the rates of raw visceral fat, and fat outcome, were established. LEP polymorphism was significantly (P<0.01 or P<0.05) associated with the proportion of adipose tissue in the morphological carcass composition in Hereford calves, and with the content of intramuscular fat in the longissimus in Limousine calves. The results of our study of TG5 and LEP polymorphism demonstrate considerable genetic potential of the given populations of the Hereford and Limousine breeds in relation to the quantitative and qualitative composition of their meat; they are to be used in improvement of genetic potential of meat cattle in the Cis-Ural steppe zone.