Association of polymorphism in 5 UTR of thyroglobulin gene with carcass traits in Afshari×Booroola Merino cross lambs

Tail and other adipose fat comprise a considerable fraction of carcass composition. This study aimed to assess association between polymorphism in thyroglobulin gene (TG) and carcass traits in Afshari sheep. To do this, a study was conducted using 97 male lambs of Afshari breed. Lambs were at age of 11 month before slaughtering. Primers were designed based on sequences available for cow. To identify different genotypes SSCP procedure were implicated on PCR products. Six different genotypes namely AA, AB, BB, AC, D- and EE were found according to the bands on non-denaturing polyacrylamide gel. There were significant differences between back fat thickness (BFT) among genotypes and BB and D- had the most and least BFT respectively. Among all genotypes, BB had lowest carcass percentage (42.7) and Longissimus dorsi muscle diameter (2.09) and live weight in animals of this genotype was also the lowest. In contrast genotype AB had the highest live weight. These results are indicating that TG can be considered as a candidate gene when improvement of the carcass quality is a goal in breeding planes