Genetic Polymorphisms of SCD1 gene and its relationship with some reproductive traits in Holstein cows in Iraq

Abstract

 The research was conducted at the Khalis cows station  in Al-Khalis district - Diyala Governorate and the central laboratory of the Faculty of Agriculture - University of Tikrit for the period from 13/12/2020 to 1/2/2022, a sample of 63 Holstein cows, with the aim of extracting the genetic material and determining the genetic polymorphism of the SCD1 gene and its relationship to reproductive traits in Holstein cows, studying the percentage of distribution of genetic structures in the cows that were studied, the allele frequency and calculating the value of chi-square (χ2) were determined. The genotypes  frequencies for the SCD1 gene in the studied cow samples were 47.62, 46.03 and 6.35% for AA, AV and VV genotypes respectively. The value of the chi-square (χ2) was highly significant (P < 0.01). The frequency of allele A  and V were 0.71 and 0.29 respectively. Some reproductive traits were significantly affected by the different genotypes of the SCD1 gene. Cows with the genotype AA achieved the highest  Days Open  (106.70 ± 5.84 days), while the genotypes VV and AV were 105.93 ± 14.25 and 92.82 ± 5.89 days respectively. The cows with AA genotype was the highest calving interval  (389.77 ± 5.90 days), while the cows of the VV and AV genotypes reached 386.75 ± 14.39 and 374.27 ± 5.96 days respectively. It can be concluded by studying the genetic polymorphism of the SCD1 gene that it is possible to improve the  reproductive traits  in cows. We also recommend applying the study to a larger sample for several seasons and different locations of the gene, while studying more economic characteristics to give more accurate results for the application of the selection and exclusion strategy.