ThirtyFrieswal lactating cows were screened for clinical and subclinical mastitis and subsequently classified into healthy, subclinically affected and clinically affected groups each group comprising of 10 cows. Polymorphism of cow lactoferrin (LTF) gene promoter was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The results showed that LFT gene promoter was polymorphic among different groups which indicated that its polymorphism was correlated to mastitis infection. The allelic frequency of C and G allele was 0.42 and 0.58 and they were associated with clinical and subclinical mastitis. It was found that LTF gene polymorphism and mastitis are highly associated with each other. پرونده مقاله