Vol. 9, Issue 1, Part O (2024)

Study related to present study implicate that the cattle dissimilar genotypic patterns of RFLP analysis of αS2 casein gene (CSN1S2) gene carried out in both Sahiwal and HF cross breeds of cow. Absence of restriction site at both the alleles that resulted in the appearance of single compact bands of size 1267bp was referred to as genotype AA known as monomorphic and noticed in Sahiwal cows. The samples exhibiting three fragments (1267bp/ 1150bp/ 117bp) were denoted as AB genotype and noticed in HF Cross bred cow. AA and AB genotypes were observed in HF Cross bred. 1.00, 0.00, and 0.00 in Sahiwal and 0.58, 0.42 and 0.00 in HF crossbred cattle, respectively and the respective gene frequency for A and B alleles were found to be 1.00 and 0.00 in Sahiwal and 0.79 and 0.21 in HF crossbred cattle. The frequency of A allele was found to be highest as compared to B allele in above both breeds of cattle under the study. Non-significant value of Chi-square was observed for testing genotypic frequencies at this locus in both Sahiwal and HF crossbred breeds. Hardy-Weinberg equilibrium was noticed in the above mentioned populations of animals. With respect of daily milk yield both AA and AB genotype of HF crossbred breeds cow showed significantly higher daily milk yield than AA genotype of Sahiwal, whereas the AB genotype of HF crossbred showed significantly higher daily milk yield than its own AA genotype.