PCR-RFLP of GH gene and its associations with milk-production traits in Malvi, Nimari and Frieswal cattle

A study was caried out to detect polymorhism in exon V of the bovine GH gene and to find out association of polymorphism with economic traits in Malvi, Nimari and Frieswal cattle. Association was analyzed between the GH gene polymorphism at exon V (GH1 locus) and milk production traits in Malvi, Nimari and Frieswal cattle. Blood samples along with records of lactation length and lactation yield were collected randomly from 50 Malvi, 25 Nimari and 50 Frieswal lactating cows. PCR-RFLP was performed for genotyping of animals. PCR exposed 427 bp long amplicon whose restriction digestion was performed by using restriction enzyme AluI. Three genotypes, viz AA, AB and BB, were found with frequency of 0.88, 0.10 and 0.02 in Malvi; 0.76, 0.24 and 0.00 in Nimari and 0.26,072 and 0.02 in Frieswal respectively. Frequencies for gene A were 0.93, 0.88 and 0.62 and for gene B were 0.07, 0.12 and 0.38 respectively in Malvi, Nimari and Frieswal respectively. Least square analysis revealed superiority of genotype AB over AA for lactation length (301.2±6.05 vs 285.17±5.32) and lactation yield (1542.98±77.33 vs 1438.12±68.04) among all the 3 breeds.