Genomic Comparison of Two Bangladeshi Zebu Breeds Inferring Regions With Traits of Economic Importance

A recently developed high-density bovine SNP 80K Bead Chip derived from Bos indicus breeds brought us the opportunity to apply on two Bangladeshi zebu breeds. Apart from the large genomic diversity has been found within the Bangladeshi red Chittagong (RC) and non-descript Deshi (ND) zebu breeds, the variation in size and production & reproduction traits are also large between the breeds. As far as the body size is concerned a potential candidate Pleiomorphic Adenoma Gene 1 (PLAG1) sequence analyzed between the breeds didn’t establish the gene attributable important for their size differences. On the other hand, the genome-wide comparison of allelic frequencies has identified differences in the markers spanning 39.8 to 61 Mb on BTA16 and some other chromosomal regions. Again an extended haplotype-based homozygosity score test (EHHST) determined strong slecetion signatures within the covered region of 35.9 to 79.6 Mb on BTA16 between RC and ND. In a study the region of 41 to 46 Mb on BTA16 has been reported for postpartum anestrous interval (PPAI) and PW trait in tropically adapted beef cattle which is essentially similar region with our study. Besides, significant evidence for differential allele frequencies between Taurine and Zebu cattle in the 35.2 to 45.2 Mb region of BTA16 has been reported. So, our study determines important genomic regions for this local cattle breeds. Further studies (genetic association) are needed to precisely suggest fertility related issues ivolving cross breeding or within breed selection programs with these local breeds.