Effect of genotypes of beta lacto globulin on milk yield and milk composition during four lactation periods in Red Sindhi cows

摘要

The present study was undertaken to study the effect of Beta lactoglobulin (-LG) genotypes on milk yield and milk composition during four lactation periods. Individual mid lactation milk samples of 75 ml of each were collected from 95 Red Sindhi cows in first, second, third and fourth lactation period maintained at Livestock research station, Hosur. Effect of genotypes of -LG AA, AB and BB on milk fat% , protein%,Casein%,Total solids% and 305 days milk yield were analysed by completely random design by least square analysis. -LG genotypes (AA, AB and BB) were found to be having highly significant (P0.01) effect on Fat% during first and second lactation and significant effect (P0.05) during third and fourth lactation respectively. -LG genotypes were found to be having significant effect on protein% during first, second, third and fourth lactation periods. Genotypes of -LG were found to be having significant effect on casein% during first lactation and highly significant effect during second, third and fourth lactation periods. -LG genotypes were found to be having significant effect on total solids % during first lactation period only and no significant effect during second, third and fourth lactation periods. -LG genotypes were found to be having highly significant effect on milk yield during first and third lactation period and significant effect during second and fourth lactation periods.