Lactoferrin, a glycoprotein, is an important antimicrobial molecule present in milk which plays a vital role in antimicrobial defence of the udder in bovines. In the present investigation, polymerase chain reaction- single-strand conformation polymorphism (PCR-SSCP) studies were carried out in 122 Deoni (Bos indicus) cows to detect SNPs of lactoferrin gene and to analyze the association between the observed polymorphisms with milk lactoferrin content and Somatic Cell Count (SCC). The PCR-SSCP analysis revealed a total of 20 different variants in the entire coding regions of the lactoferrin gene. Analysis of exons 2, 6 and 8 of lactoferrin gene revealed 4, 3 and 5 unique SSCP patterns, respectively. The PCR-SSCP analysis of exons 3, 9, 14 and 15 revealed two unique SSCP patterns. Comparison of nucleotide sequences of lactoferrin gene of the Deoni cows with taurine cattle revealed a total of 39 point mutations, 25 of which were found to be in coding region. Conceptualized translation of nucleotide sequence revealed 15 amino acid changes. The SSCP variants of exons 2 and 6 had significant (P<0.05) effect on milk SCC. The SSCP variants of exon 3 and exon 15 showed significant effect on lactoferrin content. The SCC and lactoferrin content in Deoni cows was highest in 4^th and above parity group. Somatic Cell Count was lowest in early stage of lactation. Parity was found to have highly significant (P<0.01) effect on both milk SCC and lactoferrin content. The observed association between SSCP variants in lactoferrin gene with milk SCC, and milk lactoferrin content suggests the possibility of using these genetic variants in lactoferrin gene as prognostic markers for selection of animals for high lactoferrin content, low SCC and mastitis resistance.

Key words: Deoni cows, Lactoferrin gene, Milk lactoferrin content, PCR-SSCP, SNPs, Somatic cell count