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The identification of candidate genes related to pigmentation and under selective sweep provides insights into the genetic basis of pigmentation and the evolutionary forces that have shaped this variation. The selective sweep events in the genes responsible for normal coat color in Indian cattle groups are still unknown. To find coat color genes displaying signs of selective sweeps in the indigenous cattle, we compiled a list of candidate genes previously investigated for their association with coat color and pigmentation. After that, we performed a genome-wide scan of positive selection signatures using the BovineSNP50K Bead Chip in 187 individuals of seven indigenous breeds. We applied a wide range of methods to find evidence of selection, such as Tajima's D, CLR, iHS, varLD, ROH, and FST. We found a total of sixteen genes under selective sweep, that were involved in coat color and pigmentation physiology. These genes are CRIM1 in Gir, MC1R in Sahiwal, MYO5A, PMEL and POMC in Tharparkar, TYRP1, ERBB2, and ASIP in Red Sindhi, MITF, LOC789175, PAX3 and TYR in Ongole, and IRF2, SDR165 and, KIT in Nelore, ADAMTS19 in Hariana. These genes are related to melanin synthesis, the biology of melanocytes and melanosomes, and the migration and survival of melanocytes during development. [ABSTRACT FROM AUTHOR]

Riverine Buffaloes, especially the Murrah breed because of their adaptability to harsh climatic conditions, is farmed in many countries to convert low-quality feed into valuable dairy products and meat. Here, we investigated the copy number variations (CNVs) in 296 Murrah buffalo using the Axiom® Buffalo Genotyping Array 90K (Affymetrix, Santa Clara, CA, USA). The CNVs were detected on the autosomes, using the Copy Number Analysis Module (CNAM) using the univariate analysis. 7937 CNVs were detected in 279 Buffaloes, the average length of the CNVs was 119,048.87 bp that ranged between 7800 and 4,561,030 bp. These CNVs were accounting for 10.33% of the buffalo genome, which was comparable to cattle, sheep, and goat CNV analyses. Further, CNVs were merged and 1541 CNVRs were detected using the Bedtools-mergeBed command. 485 genes were annotated within 196 CNVRs that were identified in at least 10 animals of Murrah population. Out of these, 40 CNVRs contained 59 different genes that were associated with 69 different traits. Overall, the study identified a significant number of CNVs and CNVRs in the Murrah breed of buffalo, with a wide range of lengths and frequencies across the autosomes. The identified CNVRs contained genes associated with important traits related to production and reproduction, making them potentially important targets for future breeding and genetic improvement efforts. [ABSTRACT FROM AUTHOR]

Major Histocompatibility Complex (MHC) genes are among the immune genes that have been extensively studied in vertebrates and are necessary for adaptive immunity. In the immunological response to infectious diseases, they play several significant roles. This research paper provides the selection signatures in the MHC region of the bovine genome as well as how certain genes related to innate immunity are undergoing a positive selective sweep. Here, we investigated signatures of historical selection on MHC genes in 15 different cattle populations and a total of 427 individuals. To identify the selection signatures, we have used three separate summary statistics. The findings show potential selection signatures in cattle from whom we isolated genes involved in the MHC. The most significant regions related to the bovine MHC are BOLA, non-classical MHC class I antigen (BOLA-NC1), Microneme protein 1 (MIC1) , Cluster of Differentiation 244 (CD244), Gap Junction Alpha-5 Protein (GJA5). It will be possible to gain new insight into immune system evolution by understanding the distinctive characteristics of MHC in cattle. [ABSTRACT FROM AUTHOR]

The field of genetics has evolved a lot after the emergence of molecular and advanced genomic technologies. The advent of Next Generation Sequencing, SNP genotyping platforms and simultaneous reduction in the cost of sequencing had opened the door to genomic research in farm animals. There are various applications of genomics in livestock, such as the use of genomic data: (i) to investigate genetic diversity and breed composition/population structure (ii) to identify genetic variants and QTLs related to economically important and ecological traits, genome-wide association studies (GWAS) and genomic signatures of selection; (iii) to enhance breeding programs by genomic selection. Compared to traditional methods, genomic selection is expected to improve selection response by increasing selection accuracy and reducing the generation interval due to early selection. Genomic selection (GS) in developed countries has led to rapid genetic gains, especially in dairy cattle, due to a well-established genetic evaluation system. Indian livestock system is still lagging behind developed nations in adopting these technologies. This review discusses the current status, challenges, and future perspectives of livestock genomics in India. [ABSTRACT FROM AUTHOR]

The present study was conducted on the MHC class I (BoLA-A/BuLA-A) gene in Sahiwal, Jersey, Hariana, and Tharparkar breeds of cattle and Murrah, Mehsana, and Bhadawari breeds of buffalo to study the polymorphism. Exons 7–8 of the MHC class I gene was first characterized for polymorphism study in buffalo and the results reveal that this gene has a higher level of nucleotide changes than the cattle. Genes were investigated for polymorphisms in 285 animals of cattle and buffalo breeds. Molecular characterization of the MHC class I (BoLa-A/Bula-A) gene reveals a higher degree of polymorphism at the nucleotide level in cattle and buffalo. Results revealed this region has a higher level of polymorphisms in buffalo as campared to the cattle. Alul restriction patterns were monomorphic except for three different patterns but it was able to illustrate the differences in buffalo and cattle. SSCP analysis of exons 7–8 showed remarkable differences in cattle and buffalo. Sequence analysis revealed more closeness of Murrah breed with crossbred and indigenous cattle than Holstein Friesian. Exon 8 had more deletion and stop codon as compared to exon 7. The investigation confirmed that MHC class I BoLa-A/Bula-A exons 7–8 is highly polymorphic in buffalo as compared to cattle. [ABSTRACT FROM AUTHOR]

Copy number variations (CNVs) are major forms of genetic variation with an increasing importance in animal genomics. This study used the Illumina BovineSNP 50 K BeadChip to detect the genome-wide CNVs in the Tharparkar cattle. With the aid of PennCNV software, we noticed a total of 447 copy number variation regions (CNVRs) across the autosomal genome, occupying nearly 2.17% of the bovine genome. The average size of detected CNVRs was found to be 122.2 kb, the smallest CNVR being 50.02 kb in size, to the largest being 1,232.87 Kb. Enrichment analyses of the genes in these CNVRs gave significant associations with molecular adaptation-related Gene Ontology (GO) terms. Most CNVR genes were significantly enriched for specific biological functions; signaling pathways, sensory responses to stimuli, and various cellular processes. In addition, QTL analysis of CNVRs described them to be linked with economically essential traits in cattle. The findings here provide crucial information for constructing a more comprehensive CNVR map for the indigenous cattle genome. [ABSTRACT FROM AUTHOR]

The present study was undertaken to identify the microRNAs (miRNAs) expressed in the mammary tissue of a bubaline heifer. Small RNAs were isolated from the mammary gland tissue and enriched for miRNA fraction. The linker-ligated small RNAs were reverse transcribed to synthesize cDNA and amplified by PCR. The PCR products were ligated to the pGEM-T Easy vector; cloned into DH5 alpha cells and sequenced. Sequencing of 40 clones, randomly chosen from this library, produced 115 concatemerized short sequences. The short sequences were checked for their matches with the help of refseq_rna database, EST database (NCBI) and Ensembl. The analysis was performed for more than 90% identity with miRNAs across different species in miRBase. Alignment of putative small RNA sequences with the bovine genome was attempted in GenBank (NCBI) and Ensembl using BLAST. The small RNA sequences with a partial matches within the bovine genome and/or with flanking sequences (upstream or downstream) were analyzed for hairpin structures using the Mfold web server. Reverse complements were also assessed for the homology search. miRNA sequences showing only a partial match with already reported sequences were considered as a putative bubaline miRNAs. Six developmentally important putative miRNA precursors were identified from this study using cloning and sequencing followed by the Bioinformatics approach. This study will help in the elucidation of pathways involving miRNAs in bubaline species at the heifer stage. [ABSTRACT FROM AUTHOR]

Knowledge about genetic diversity is very essential for the management and sustainable utilization of livestock genetic resources. In this study, we presented a comprehensive genome-wide analysis of genetic diversity, ROH, inbreeding, linkage disequilibrium, effective population size and haplotype block structure in Tharparkar cattle of India. A total of 24 Tharparkar animals used in this study were genotyped with Illumina BovineSNP50 array. After quality control, 22,825 biallelic SNPs were retained, which were in HWE, MAF > 0.05 and genotyping rate >90%. The overall mean observed (HO) and expected heterozygosity (HE) were 0.339 ± 0.156 and 0.325 ± 0.129, respectively. The average minor allele frequency was 0.234 with a standard deviation of ± 0.131. We identified a total of 1832 ROH segments and the highest autosomal coverage of 13.87% was observed on chromosome 23. The genomic inbreeding coefficients estimates by FROH, FHOM, FGRM and FUNI were 0.0589, 0.0215, 0.0532 and 0.0160 respectively. The overall mean linkage disequilibrium (LD) for a total of 133,532 pairwise SNPs measured by D' and r2 was 0.6452 and 0.1339, respectively. In addition, we observed a gradual decline in effective population size over the past generations. [ABSTRACT FROM AUTHOR]

Single nucleotide polymorphisms (SNPs) have now replaced microsatellite markers in several species for various genetic investigations like parentage assignment, genetic breed composition, assessment for individuality and, most popularly, as a useful tool in genomic selection. However, such a resource, which can offer to assist breed identification in a cost-effective manner is still not explored in cattle breeding programs. In our study, we have tried to describe methods for reducing the number of SNPs to develop a breed-specific panel. We have used SNP data from Dryad open public access repository. Starting from a global dataset of 178 animals belonging to 10 different breeds, we selected five panels each comprising of similar number of SNPs using different methods i.e., Delta, Pairwise Wright's FST, informativeness for assignment, frequent item feature selection (FIFS) and minor allele frequency–linkage disequilibrium (MAF-LD) based method. MAF-LD based method has been recently developed by us for construction of breed-specific SNP panels. The STRUCTURE software analysis of MAF-LD based method showed appropriate clustering in comparison to other panels. Later, the panel of 591 breed-specific SNPs was called to their respective breeds using Venny 2.1.0 and UGent web tools software. Breed-specific SNPs were later annotated by using various Bioinformatics softwares. [ABSTRACT FROM AUTHOR]

The present study was aimed at genetic characterization and diversity analysis of Pandharpuri buffalo population using the Food and Agriculture Organization (FAO) recommended bovine microsatellite markers. Genomic DNA was isolated from blood samples of 50 unrelated animals and a total of 23 microsatellite loci were amplified using polymerase chain reaction. Among 23 recommended microsatellite markers, 14 markers (BM2113, BM1818, CSSM66, HEL13, INRA037, ILSTS05, HAUT27, INRA023, INRA035, HEL5, ETH3, NRA063, MM12 and ETH10) were found to be highly polymorphic in Pandharpuri population. The amplified products were run on polyacrylamide gel electrophoresis (PAGE) apparatus along with a ladder; subsequently, the allele typing was done based on silver staining of the gel. The effective and observed number of alleles, heterozygosity (expected and unbiased) estimates and polymorphic information content (PIC) levels were estimated for each locus. A total of 87 alleles were secured for 14 polymorphic loci studied giving an overall average of 6.21 alleles per locus. The number of alleles ranged from 2 (INRA063) to 9 (BM1818 and HEL13). The mean effective number of alleles across all polymorphic loci was found to be 4.28. The overall mean expected heterozygosity and unbiased expected heterozygosity values were 0.77 and 0.76, ranging from 0.50 (INRA063) to 0.88 (BM1818) and 0.50 (INRA063) to 0.88 (BM1818), respectively. The average PIC estimate across all polymorphic loci was 0.73 ranging from 0.373 (INRA063) to 0.864 (BM1818). In the present study, the characterization and diversity estimates are reported for Pandharpuri population. It was found to maintain optimum diversity based on 14 polymorphic microsatellite markers. [ABSTRACT FROM AUTHOR]

The present study aimed to evaluate the efficiency of two Bovine SNP genotyping arrays (i.e., 50 K and HD) for breed clustering and stratification related studies in taurine and indicine breeds. The whole-genome SNP data at two densities were assembled into three datasets (A, B and C). Dataset A (N = 213) included 50 K genotypic data for five taurine (Holstein–Friesian, Guernsey, Brown Swiss, Angus and Jersey) and two indicine (Gir and Nellore) breeds. Dataset B (N = 241) included the same breeds with HD density data. Dataset C (N = 299) included 50 K SNP genotypic data for six taurine (Holstein–Friesian, Jersey, Guernsey, Brown Swiss, Angus and Hereford) and six indicine (Hariana, Kankrej, Brahman, Nellore, Sahiwal and Gir) breeds. The analysis was done using ADMIXTURE program (bioinformatics-based) and cross-validation errors and Principal Component Analysis (statistical analysis). The proportion of polymorphic markers and minor allele frequencies were assessed for each breed. The proportion of markers polymorphic was consistently higher in taurine breeds when compared with breeds from indicine group. Minor allele frequency estimates and ADMIXTURE results showed differential patterns for both the lineages. However, no significant increase in the accuracy of genomic clustering was found on moving from 50 K to HD density data. [ABSTRACT FROM AUTHOR]

The present study was aimed to assess parameters related to genetic diversity, population structure and admixture in the Frieswal crossbred cattle of India. A total of three datasets were analyzed during this study. Dataset A (n = 80) consisted of data on two purebred populations, i.e., Shorthorn (n = 35) and Brahman (n = 25) and one crossbred strain Santa Gertrudis (n = 20). The dataset B (n = 71) consisted of data on three populations that included Holstein-Friesian (n = 30), Sahiwal (n = 27) and Frieswal (n = 14) cattle. The dataset C included data on all the six breeds under study. Dataset C was used to assess the indices of population structure and genetic diversity of different breeds prior to and after LD pruning. For Frieswal cattle strain, the proportion of polymorphic SNPs and MAF levels was 84.54% and 0.24, respectively. Frieswal strain maintained appreciable genetic diversity with observed heterozygosity measure of 0.414. PCA plots for three datasets depicted effective stratification of different breeds in the respective datasets. The genomic clustering levels of Sahiwal and Holstein-Friesian were found to be 98.45 and 99.89%, respectively, while the admixture of Frieswal was estimated to be about 61.5 and 38.5% from Holstein-Friesian and Sahiwal breeds, respectively. [ABSTRACT FROM AUTHOR]

Subclinical mastitis, generally caused by Staphylococcus aureus, has a global economic impact all over the world. Hence, it needs to be resolved on higher priority which may be attained via. selection of mastitis resistant animals or inclusion of mastitis resistant trait into herd apart from management care. Diverse hosts with various genetic make-ups encounter pathogens in a diverse manner which in turn leads to contradicting outcome of the disease. Identification of species-wise or breed-wise differential expressed genes in response to S. aureus through relative evaluation of transcripts may be useful for judging the immuno-competency of a species or breed toward mastitis. The present study was undertaken to examine the stimulant effect of S. aureus peptidoglycan (PGN) and lipoteichoic acid (LTA) on Peripheral blood mononuclear cells (PBMC) harvested from blood samples of crossbred cattle, Tharparkar cattle, and Murrah buffaloes. After 6 h of in vitro stimulation qRT-PCR was used to measure the relative mRNA expression of TLR-2, TNF-α, IL-8, IFN-γ and IL-10 genes in stimulated and un-stimulated PBMC. The selected genes revealed significant differences in the pattern of immune response among crossbred cattle, Tharparkar cattle and Murrah buffalo in spite of the same stimulant dose. [ABSTRACT FROM AUTHOR]

The present investigation was performed to compare the global gene expression profile in peripheral blood mononuclear cells (PBMCs) of Bos indicus and crossbred (Bos taurus × B. indicus) cattle. Previously, several studies revealed the disease tolerance potential of B. indicus cattle but underlying genetic mechanism is still not fully explored. The PBMCs model was used for this investigation as it plays crucial role in the immune system regulation. Transcriptomic analysis revealed total 6767 significantly differentially expressed transcripts (fold change (absolute) >2.0, p <.05). In addition, 4149 transcripts were upregulated, 2618 transcripts were downregulated and fold change (absolute) of differentially expressed transcript varied from −223.32 to 213.63. Functional annotation analysis of differentially expressed genes confirmed their role in various molecular pathways viz. innate immune response, antigen processing and presentation, MHC protein complex, defense response to bacterium, regulation of immune response, positive regulation of JAK-STAT cascade, cytoskeletal protein binding, etc. Protein–protein interaction network analysis provided understanding of inter-relationship of immune genes with differentially expressed genes. In conclusion, this study could provide comprehensive information about the dysregulated genes and biological pathways in PBMCs which might be responsible for disease tolerance in B. indicus cattle. [ABSTRACT FROM AUTHOR]

The BoLA class II DQA and DQB genes in crossbred cattle were studied using PCR-RFLP, cloning, and sequencing techniques. Seventy-two crossbred cattle (Vrindavani) were used in the current study. HaeIII and XbaI restriction enzymes digested DQA exon 2-3, revealing seven (HaeIII-A-G) and three (XbaI A-C) motifs, respectively. The BoLA-DQB gene was analyzed using PCR-RFLP with PstI and TaqI restriction enzymes, yielding five restriction motifs for each restriction enzyme (PstI-A-E and TaqI-A-E). In crossbred cattle, addition, deletion, and substitutions were observed in distinct sequences, resulting in variations in overall gene length. Changes in nucleotides at positions 64–80, 110–200, and 207–264 were largely responsible for polymorphism in DQA exon 2. The phylogenetic analysis predicted a high degree of nucleotide and amino acid changes in DQA exon 2-3 and DQB exon 2. DQA genes had a nucleotide dissimilarity of 0.3–25.4 percent, while DQB genes had a nucleotide dissimilarity of 1.5–14.3 percent. We cloned and sequenced 20 genotypes based on PCR-RFLP of the DQA and DQB genes. The current study observed variation in the DQA and DQB genes and will serve as a foundation for future research on the BoLA DQA and DQB genes. [ABSTRACT FROM AUTHOR]

Crossbred cattle are more prone to mastitis in comparison to indigenous cattle. Toll-like receptor 4 (TLR4) recognizes pathogen ligands, for example, lipopolysaccharide (LPS) endotoxin fromEscherichia coliand mediates signaling to initiate innate and adaptive immune responses. Mutations in TLR4 can compromise the host immune response to certain pathogens, so it may be a potential candidate for marker assisted selection to enhance mastitis resistance in dairy cattle. Hence, in this study role of bovine TLR4 gene in mastitis resistance was investigated by association as well as expression profiling analysis in crossbred cattle. The animals were divided into mastitis affected and unaffected groups on the basis of history of animals and California Mastitis Test (CMT). PCR-SSCP and Sequence analysis revealed three genotypes of coreceptor binding region 1 (CRBR1) fragment of TLR4 gene namely AA, AB, and BB in both groups of cattle. The logistic regression model did not show any significant effect of these genotypes on the occurrence of clinical mastitis. Moreover, in vitro challenge of peripheral blood mononuclear cells (PBMCs) with LPS failed to show any association of the genotypes with TLR4 gene expression. In a nutshell, in the present study enough evidence was not found for association of the SNP variants of CRBR1 fragment of TLR4 gene with mastitis susceptibility in crossbred cattle. [ABSTRACT FROM PUBLISHER]

The detection of selection signatures assists in understanding domestication, evolution, and the identification of genomic regions related to adaptation and production traits in buffaloes. The emergence of high-throughput technologies like Next Generation Sequencing and SNP genotyping had expanded our ability to detect these signatures of selection. In this study, we sought to identify signatures of selection in five buffalo populations (Brazilian Murrah, Bulgarian Murrah, Indian Murrah, Nili-Ravi, and Kundi) using Axiom Buffalo 90 K Genotyping Array data. Using seven different methodologies (Tajima's D, CLR, ROH, iHS, FST, FLK and hapFLK), we identified selection signatures in 374 genomic regions, spanning a total of 381 genes and 350 quantitative trait loci (QTLs). Among these, several candidate genes were associated with QTLs for milk production, reproduction, growth and carcass traits. The genes and QTLs reported in this study provide insight into selection signals shaping the genome of buffalo breeds. Our findings can aid in further genomic association studies, genomic prediction, and the implementation of breeding programmes in Indian buffaloes. [ABSTRACT FROM AUTHOR]

The present study in the 5’ upstream region of TLR4 gene revealed four Single Nucleotide Polymorphisms (SNPs) in Vrindavani and Tharparkar cattle. The polymorphic information content (PIC), heterozygosity and allelic diversity values were low to moderate for these SNPs. In Vrindavani cattle, one SNP was found to be in Hardy-Weinberg Equilibrium (HWE) and the remaining three were found to be in linkage disequilibrium (LD) as indicated statistically (P > 0.05). In Tharparkar cattle, two SNPs were found to be in HWE and were not in LD as indicated statistically (P > 0.05). These SNPs were used for construction of haplotypes. In-silico analysis of these SNPs predicted abolition of eight transcription factor binding sites and creation of eight new sites. The quantitative real time PCR analysis did not show any significant variation of gene expression among haplotypes. However, gene expression between breed was found to be significant (P < 0.05) which suggested that upstream region of bovine TLR4 gene has a crucial role in its expression. These findings in TLR4 gene offer essential evidence that can be useful in future research exploring its role in immunity. TLR4 can be used as a marker for selection for disease resistance in bovines. [ABSTRACT FROM AUTHOR]

Classical Swine Fever (CSF) is a contagious viral disease of pigs which is endemic in several parts of the world, including India. Prophylactic vaccination using live attenuated vaccine is the preferred method of control. However, there is significant inter-individual variation in the antibody response to vaccination. In this study, we measured the E2 antibody blocking percentage after 21 days of CSF vaccination in a mixed pig population consisting of Landrace, indigenous Ghurrah pigs, and their crossbreds. A Genome Wide Association Study (GWAS) carried out using single-SNP and haplotype based methods detected a 1.6 Mb region on SSC2 (28.92−30.52 Mb) as significantly associated with antibody response to CSF vaccination. The significant region and 1 Mb flanking sequences encompass 3 genes – EIF3M, DNAJC24 and ARL14EP, which code for proteins involved in Pestivirus replication and host immune response system. Our results combined with previous studies on immune response of pigs present this region as a suitable candidate for future functional investigations. [ABSTRACT FROM AUTHOR]

A total of 129 crossbred cows were selected to explore the genotypic and expression profiling of partial TNF-α gene and its association with mastitis susceptibility. Two exon spanning region of TNF-α gene (221 bp and 239 bp) were amplified by Polymerase Chain Reaction (PCR). The different genotypic analysis by SSCP revealed that 221 bp fragment was monomorphic, whereas 239 bp was polymorphic. Association studies revealed that AA genotypes of 239 bp were more prevalent in mastitis group and the mRNA expression of TNF-α was significantly (P < 0.05) higher in AA genotypic animals compare to AB and BB. This suggested that genotypes AB and BB may be used as candidate markers for mastitis resistance selection in dairy cattle. [ABSTRACT FROM AUTHOR]