فهرست نشریات علمی دسترسی آزاد ایران

The globally increasing demand for meat is driving the implementation of efficient agricultural and genetic techniques to improve productivity. Meat traits, the key target in sheep breeding programs, have obviously linked to economic viability. A Myostatin (MSTN) gene, negatively regulating the development of skeletal muscle, is associated with important variations in muscle development and meat production efficiency. Therefore, this study aimed to identify the genetic polymorphisms of the G>T-840 variation in MSTN gene and investigate its relationship with carcass traits and meat characteristics of Iraqi Nuaimi sheep. The results indicated that variant G>T-840 (SNP) has three genetic polymorphisms GG (44.68%), GT (42.55%), and TT (12.77%). The allelic frequencies were 0.66 and 0.34 for G and T alleles, respectively, and the chi-square value was 10.617, which was highly significant at P≤0.01. Significant differences (P≤0.05) between the genotypes (GG, GT, and TT) were observed in the loin eye muscle area, with values of 18.71, 18.25, and 16.10 cm² respectively. The TT genotype showed significantly (P≤0.05) higher fat layer thickness between the 12th and 13th ribs (6.38 mm) and in the carcass length (55.75 cm) compared with the GG and GT genotypes. The genotypes have not shown significant differences in the other traits studied, and in the chemical composition of the longissimus dorsi muscle. In conclusion, the genetic variations in the MSTN gene might contribute to improving genetic selection of sheep and enhance meat productivity, providing a scientific basis for more economically and productively efficient breeding strategies.