Milk protein genes CSN1S1, CSN2, CSN3, LGB and their relation to genetic values of milk production parameters in Czech Fleckvieh

Genotypes of milk protein genes, alphaS1-casein (CSN1S1), beta-casein (CSN2), kappa-casein (CSN3) and beta-lactoglobulin (LGB), were detected in 440 individuals of Czech Fleckvieh breed using a PCR-RFLP method. A granddaughter design including 5 grandsires, 33 sons and 402 granddaughters was used for evaluation. Statistical analysis was carried out in SAS program using a restricted maximum likelihood method. Positive findings of frequencies of CSN3 allele B (0.38) and genotype BB (13%) were detected. Significant differences were found between genotypes of loci CSN1S1, CSN2 and CSN3 and breeding values for milk production parameters. Genotypes of LGB locus were not significantly related to any of the milk production parameters. Significant effects were found between CSN1S1 locus and average breeding value for milk yield, CSN2 locus and breeding values for all parameters except for protein content and CSN3 locus and breeding values for protein content and protein yield.