Arunachali yak, the only registered yak breed of India, is crucial for the economic sustainability of pastoralist Monpa community. This study intended to determine the genomic diversity and to identify signatures of selection in the breed. Previously available double digest restriction-site associated DNA (ddRAD) sequencing data of Arunachali yak animals was processed and 99,919 SNPs were considered for further analysis. The genomic diversity profiled based on nucleotide diversity, π (π = 0.041 in 200 bp windows), effective population size, Ne (Ne = 83) and Runs of homozygosity (ROH) (predominance of shorter length ROHs) was found to be optimum. Subsequently, 207 regions were identified to be under selective sweeps through de-correlated composite of multiple signals (DCMS) statistic which combined three individual test statistics viz. π, Tajima’s D and |iHS| in non-overlapping 100 kb windows. Mapping of these regions revealed 611 protein-coding genes including KIT, KITLG, CDH12, FGG, FGA, FGB, PDGFRA, PEAR1, STXBP3, olfactory receptor genes (OR5K3, OR5H6 and OR1E1) and taste receptor genes (TAS2R1, TAS2R3 and TAS2R4). Functional annotation highlighted that biological processes like platelet aggregation and sensory perception were the most overrepresented and the associated regions could be considered as breed-specific signatures of selection in Arunachali yak. These findings point towards evolutionary role of natural selection in environmental adaptation of Arunachali yak population and provide useful insights for pursuing genome-wide association studies in future.

Bos indicus breed Sahiwal, famous for its optimum performance, has so far been genetically improved for performance traits based on phenotypic records and the genomic knowhow regarding genes, regions and biological processes underlying the complex quantitative traits is lacking. In this context, a Genome-wide Association Study was performed for fertility and growth traits in Sahiwal cattle to shed light on its genomic profile. A total of 46 SNPs were found associated with the traits at genome-wide suggestive threshold of P ≤ 10⁻⁴. USP32, LRPPRC, PLA2G10, RRN3 and ASAP1 were identified as putative candidate genes for body weight at different ages. However, several genes mapped for growth traits like GREB1, PLA2G10, RAD51C, BIRC6, TEX14 and PEBP4 had significant physiological underpinnings in determining fertility of the animals. Moreover, Quantitative trait loci (QTL) identification revealed potential overlaps with the already reported QTLs for both fertility and growth for most of the traits. Further, candidate SNP enrichment analysis revealed an enriched biological process for birth weight with a significant reproductive role. Based on the findings, genetic linkages underlying fertility and growth could be discerned in Sahiwal population and may be utilized for improving fertility traits in future.

Highland pastoralism provides economic sustainability to the tribal livelihoods and is endemic to the yak-rearing tracts of India. Transhumant pastoralists of Arunachal Pradesh (in India) have centuries-old deep socio-religious and economic connections with this unique bovine species. As a result of their conservation efforts, Arunachali was recognized as the first and is still the lone breed (to date) of yaks in the country. A survey was conducted on the pastoral production system in the region to enable the phenotypic characterization of yaks and to understand the prevailing husbandry practices. Arunachali yaks are medium-sized bovines that are predominantly black with dense and long hairs hanging down the body and are docile in temperament. They have a convex head with horizontal ears and distinctly curved horns with pointed tips. The average milk yield is 0.98–1.04 kg milk/day with 7.45% fat and 11.5% SNF and the peak milk yield/day is 1.1–1.6 kg. The average ages of clipping of coarse hairs and down fibres are 12–18 months and 12 months, respectively, with average yields of 1.5 kg and 0.5 kg/clipping/animal, respectively. Value addition of yak milk and fibre presents a unique opportunity for the economic rejuvenation of yak pastoralism. However, winter feed scarcity, inbreeding, extreme climate events and the non-availability of essential services are still major challenges for yak production in the country. Our findings acknowledge that pastoral sustainability is critical for the conservation of yaks and yak rearing. This calls for pastoralism-centric governance and research efforts in the highlands to curb the declining population and to put Indian yaks on the road to sustainability.