Effect of ß-lactoglobulin Locus Polymorphism on Milk Related Traits in Romanian Spotted

The main aim of the study was to assess the influence of ß-lactoglobulin (LGB) genotype on milk related traits in Romanian Spotted (R.S.) breed. Altogether 254 cattle were genotyped for in order to establish the share of A and B allele in LGB locus using PCR-RFLP assay. The most prevalent was A allele (0.662) compared to B allele (0.338). Comparable frequencies (P>0.084) were recorded for AA (0.434) and AB (0.455) genotypes. The BB heterozygous recorded a lower frequency (0.111) compared with others (P≤0.001). For the LGB polymorphism, no significant differences (P>0.05) were observed according to milk production. The higher milk production was associated to AB (6094.31±103.22 kg) compared to AA (5912.22±91.7 kg, P>0.53) and BB (5977.7±81.12 kg, P>0.71) genotypes. The higher fat percentage (4.26±0.02%) was recorded for BB genotype, compared to AA genotype (4.19±0.02%, (P≤0.019). A significantly increased protein percentage was associated with AB genotype (3.43±0.03%) compared with AA (3.28±0.02%, P≤0.027). No significant difference (P>0.66) was recorded compared to BB genotype (3.42±0.01%) related to this trait. The results obtained encourage including marker assisted-selection and use the genotyped sires for genes with economic values in the future breeding scheme of Romanian Spotted breed