Laboratory for Molecular Genetics and Animal Biotechnology, Faculty of Animal Science and Fisheries, Sari Agricultural Sciences and Natural Resources University, Sari, Iran
Mastitis is one of the most serious and costly diseases affecting dairy cattle production. In the present study, effects of a lactoferrin gene polymorphism (intron 6) on milk somatic cell count (SCC) and subclinical mastitis was investigated in 121 Holstein dairy cattle. Two alleles of A and B and two genotypes of AA and AB were found in an EcoRI recognized single nucleotide polymorphism in intron 6 of lactoferin gene with the frequencies of 85.12, 14.88, 70.25 and 29.75%, respectively. No homozygous BB cows were detected in the studied population. Marker-traits association analysis showed that EcoRI marker site in lactoferrin gene was significantly related to SCC (P≤0.01) with AB as a desirable genotype. The obtained results in the present study indicated that selection of the AB genotypes for EcoRI recognized single nucleotide polymorphism might contribute to a reduction of SCC in Holstein dairy cattle.