Document Type : Research Paper

Authors

• Maryam Bazgiri ¹
• Mohammad taghi Beigi nassiri ²
• Jamal Fayazi ³

¹ M.Sc. Graduated, Faculty of Animal Science and Food Technology, Ramin University of Agriculture and Natural Resources of Khouzestan

² Professor,Faculty of Animal Science and Food Technology, Ramin University of Agriculture and Natural Resources of Khouzestan

³ Associate Professor, Faculty of Animal Science and Food Technology, Ramin University of Agriculture and Natural Resources of Khouzestan

Abstract

This study was conducted to investigate the Single nucleotide polymorphism of STAT1 gene by PCR-RFLP technique and association of genotypes with milk production traits in Brown Swiss dairy cattle. The blood samples of ninety-eight cows were collected randomly from tail vein. The DNA was extracted with Cinagene kit (PR881612C). Fragment of 314 bp in 3'UTR of STAT1 gene was amplified by PCR and digested by Pag1 restriction enzyme. Genotype frequencies were calculated by PopGene software (version 1.31). The SAS 9.1 software was used for statistical analysis and the mean of traits was compared by Duncan test. The genotype
frequencies of TT, TC and CC were 0.23, 0.25 and 0.52, respectively. The T and C allele frequency were 0.355 and 0.645, respectively. The expected heterozygosity was estimated 0.458. Result of Chi-square showed that this locus was not in the Hardy Weinberg equilibrium (P<0.05). The means of traits for milk, fat percent and fat yield, and protein yield were not significant but means of protein percent was significant (P<0.05). The mean of milk, fat and protein yield traits for CC genotype were more than two other genotypes. The results of present study showed that T allele is known as minor frequency allele and C allele have positive effect on milk, fat and protein yield traits.

Keywords

• Brown Swiss breed
• Gene
• Milk production traits
• STAT1