Study of β-Lactoglobulin milk protein variants in buffalo

Polymorphism exists in β-lg milk encoding gene in dairy animals which results in different protein isoforms being expressed in the milk. overall quality of raw milk,total milk protein and fat content,depends on which β-lg isoforms are being expressed. present study was planned to identify beta-lactoglobulin (β -lg) protein isoforms in bubalus bubalis (riverine buffalo) nili ravi breed milk and to explore their association with major milk constituents. β-lactoglobulin protein variants were typed using sodium dodecyl sulfate polyacrylamide gel electrophoresis (sds-page). total milk protein and whey contents were estimated using bradford 1976 method while total milk fat by gerber method. three β-lg protein isoforms aa,bb and ab were identified with genotype frequencies; 0.49,0.10 and 0.40 respectively. allele a,with higher frequency of 0.69,was found more prevalent in studied animals as compared to b allele. the aa and ab isoforms were associated with high total milk protein contents (4.36%) while ab isoform had high whey protein (1.0%) and total milk fat (6.06%) contents. overall we report three β-lg protein isoforms (aa,ab and bb) in nili ravi buffalo milk which show significant association with major milk constituents. copyright 2014 zoological society of pakistan.