Mitogenome diversity and evolution of Bos indicus cattle in India

Mitochondrial DNA has been widely utilized as a valuable tool for studying the evolutionary and demographic history both within and between different livestock speciesover the past three decades. Evaluation of the evolutionary history, population structure and genetic diversity is imperative for their productivity, ecosystem services, and breeding and conservation strategies for effective management. The present study included complete mitogenome of 78 cattle, out of which 33 samples belonged to 6 Bos indicus breeds of India. Mitogenome diversity of zebu cattle within population (π- nucleotide, haplotype diversity) was estimated using DnaSP v6 software and between populations (F_ST ratio, AMOVA analysis) was estimated using Arlequin 3.5.2.2. Ladakhi breed showed maximum (π = 0.00645) while Gir (π = 0.00042) and Tharparkar (π = 0.00053) showed minimum diversity. The diversity between the breeds of Indian cattle was 16.34 %. There were 13 and 14 haplotypes in each of I₁ and I₂ halogroups respectively suggesting that the divergence of Bos indicus haplotypes likely occurred within the Indian subcontinent. The Bos indicus and Bos taurus cattle lineages separated approximately 0.75 million years ago. The divergence pattern observed in zebu cattle highlighted the probability of a distinct ancestor and supported notion of independent divergence of Bos indicus.