Document Type: Original Article


Department of Animal Science, College of Agriculture, Isfahan University of Technology, Isfahan 84156-83111, Iran


This experiment was aimed to study the association between the DGAT1 K232A polymorphism and milk production traits and somatic cell score (SCS) in Iranian Holstein dairy cows. The records of 408 animals from five dairy herds were randomly identified and then genomic DNA was extracted from blood using the modified-salting method described by Miller. RFLP-PCR was performed to obtain all the polymorphisms and two alleles, K and A were observed with frequency of 0.37 and 0.63. Genotypic frequencies of AA, KA and KK were 0.3578, 0.5515 and 0.0907, respectively. The relationship between DGAT1 K232A and milk traits and somatic cell score in the first lactation was studied. The results showed significant difference (p≤0.05) between the genotypes on milk production, fat percent but not for protein percent and SCS. According to this research, the DGAT1 K232A polymorphism can be considered for increasing milk performance traits in Holstein dairy cows in the proximal region of bovine chromosome 14.


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