Abstract
Selection based on genetic makeup became an important tool in genetic improvement. The development of molecular biology opened the way to study the genes of farm animals and genetically improve them. The aim of this study was to determine the Allele frequency and genotype distribution of the SCD1 gene and its relationship to milk production and its main components from fat, protein, lactose and non-fat solids percentage in Iraqi Awassi sheep. Fifty-one female Awassi sheep were used in this study. The genotype distribution of the SCD1 gene in the studied Awassi sheep sample was 50.98, 41.18 and 7.84% for each of the CC, CA and AA genotypes, and the discrepancy between these percentages were highly significant (P≤0.01), and the appearance of the C and A alleles with a frequency of 0.72 and 0.28 respectively, highly significant differences (P≤0.01) appeared in the total milk production according to the genotype. As for the milk components, it was found that there were significant (P≤0.05) differences in the percentage of fat and the percentage of non-fat solids. From the results of the current study, it can be concluded that the SCD1 gene can be adopted as an important indicator in developing genetic improvement strategies for Awassi sheep to maximize the economic return from breeding projects by selecting and cross-breeding the genotypes that achieved the best product performance.