Executive Summary : | Cattle breeds have evolved over decades due to intense artificial selection efforts focusing on production and reproduction traits. This has led to changes in genomic regions responsible for specific breed characteristics such as coat color, horn pattern, heat tolerance, disease resistance, and production and reproduction performance. These unique patterns or footprints are identified as selection signatures. Identification of selection signatures in livestock species is an emerging concept due to its ability to find genes associated with economically important traits and adaptive traits. Several literatures have been available on identification of selection signatures in taurine breeds of cattle. In India, selection signatures were identified in Virndavani cattle using Bovine SNP 50K Bead Chip, suggesting 11 common regions harboring genes associated with both production and adaptation traits. Studies on seven Indian cattle breeds, including Kangayam, Bargur, Pulikulam, Umblacherry, and Alambadi, using high density SNP array (777 K SNPs), have shown variations in stature. The present study aims to identify selection signatures in south Indian draught type cattle, specifically Kangayam, Bargur, Pulikulam, Umblacherry, and Alambadi, of Tamil Nadu state. These breeds have evolved over decades adapted to their local environmental conditions and low input management or nomadic pastoralism. There is no literature on selection signatures in native cattle breeds of Tamil Nadu, which are mostly of draught type. The study proposes that using SNP markers could shed light on their evolutionary adaptation to local agro-climatic conditions. |