INTER-SPECIES SNPS FROM BUFFALO LIVER TRANSCRIPTOME INDICATE DIVERSITY IN IMMUNE PATHWAYS BETWEEN BUFFALO AND CATTLE

Understanding genetic variation among species and breeds of dairy animals is utmost important for selection of efficient animals that could balance the energy needs during transition period.During transition period, the energy demands for milk production surpass the energy intake, leading to negative energy balance (NEB), which is common in high yielding dairy cows and buffaloes.However, the genetic variations between cows and buffaloes influencing NEB were not reported.Therefore, the present study is targeted to identify such genetic differences.ABSTRACT: The duration of negative energy balance (NEB), a physiological adaptation in females during early postpartum, and its coping mechanisms vary among animals, breeds, and species because of genetic differences.However, genetic variations that may influence the NEB differences between cattle and buffaloes were not reported.Therefore, the present study aims to identify such genetic differences between cattle and buffaloes by identifying inter-species single nucleotide polymorphisms (SNPs) by mapping the available liver RNA-seq data earlier obtained from three early postpartum buffaloes and three heifers to the cattle genome (UMD 3.1) using the SNP eff tool.The liver transcriptome data were chosen, because the liver is the major metabolic organ responsible for balancing metabolic milieu to meet different physiological demands during early postpartum.Using the identified interspecies SNPs, intragenus SNPs (Buffalo) were derived from six different Murrah buffaloes and mapped them to the Bubalus bubalis (ASM312139v1) genome.Further, functional annotation and biological pathway analyses were performed for those genes harbouring the putative SNPs.We identified a total of 1,40,056 interspecies and 188 intragenus SNPs.Functional annotation and pathway analyses revealed that most of the putative interspecies SNPs between the cattle (Bos taurus UMD 3.1) and buffalo (Bubalis bubalus) were in the protein metabolism genes (>1900) predominantly involved in the immune system (>1800 genes).Similarly, most of the putative intragenus SNPs among buffaloes were in the genes of lipid metabolic pathways.In conclusion, our study suggests that cattle and buffaloes might differ in protein metabolism genes involved in immunity at the deoxyribonucleic acid (DNA) level.