Construction of new selection criteria for Malpura sheep

Malpura sheep is one of the heavy mutton type sheep breeds found in semi-arid region of Rajasthan. Objective of the study was to revise the earlier selection criteria and set up a new one for Malpura sheep. The data on 2,995 Malpura sheep descended from 188 sires and 1,021 dams for 11 years (2004–2014) was used to construct the indices using various combination of traits. Genetic parameters were estimated for the traits to be included in the analysis for the data. Estimate of additive genetic variance for 6 month live weight (6WT) was low (h2 = 0.19±0.04). It was recommended to incorporate external germplasm for enhancing the additive genetic variability of the flock. The selection indices were constructed and highest accuracy (51.9%) was observed for the index that involves weaning weight (WWT) and first greasy fleece weight (GFW). Estimated genetic gain after 1 generation post selection was measured to be 221 g in WWT and 81.753 g in GFW. Possibility of direct selection for single trait (6WT) was explored. Results revealed higher response for 6WT (897 g) and high correlated response for other traits such as WWT (0.566 kg), ADG1 (5.601 g), ADG2 (3.132g) and GFW (26.52 g) as compared to index selection. As milk yield of dam has strong influence on pre-weaning gain, preliminary selection at weaning followed by direct selection at 6 month age based on single trait selection (6WT) was recommended as selection criteria

Factor analysis for udder and teat type traits in Sahiwal and Karan Fries cows

Selecting female cows for productivity based on udder and teat traits is essential in field due to lack of available records. The objective of the present study was to reduce the dimensionality of the 17 udder and teat traits and to analyse their impact on milk productivity. The data on 256 cattle comprising 133 Sahiwal and 123 Karan Fries cows were used in this study over the years 2017-2019 from Livestock Research Centre (LRC) of ICAR-National Dairy Research Institute, Karnal. The 17 udder and teat traits were fore udder attachment (FUA), rear udder width (RUW), rear udder height (RUH), udder balance (UB), udder depth (UD), udder length (UL), udder width (UW), udder circumference (UC), central ligament/udder cleft (CL), teat circumference (TC), fore teat length (FTL), rear teat length (RTL), distance between fore and rear teat (DFR), distance between left and right teat (DLR), shortest distance from floor to fore teat (SDFT), shortest distance from floor to rear teat (SDRT) and teat diameter (TD). In the factor analysis, first five latent factors accounted for 62.22% of total variance in udder and teat measurements for Sahiwal cows and 65.67% in Karan Fries (KF) cows, respectively. In Sahiwal cows F1 represented better udder support and wideness (wide udders, udders were supported by strong suspensory ligament), whereas in KF cows, first factor reflected better udder dimension and distance between teats (longer length, width of udder and well placed teats). Factor analysis could reduce the multicollinearity of the data. It can be concluded that inclusion of udder and teat measurements in selection index can be a reliable criteria for selecting cows for higher milk yield

Sequence based typing for BoLA-DQA1 alleles in Indian zebu and its crossbred populations

Polymorphism in the major histocompatibility complex of the bovine, which is referred to as bovine leukocyte antigens (BoLAs), was intensively investigated for identifying marker(s) for bovine diseases and immunological traits. This approach requires identifying and documenting the allelic diversity of BoLA among different breeds of cattle using PCR-SBT technique. In this study, we could standardise the most useful approach of unravelling polymorphism in DQA1 exon 2 of cattle using PCR-sequence based typing (SBT). We could identify 16 different DQA1 alleles in 43 zebu and crossbred cattle, out of which 26 were homozygous and 17 were heterozygous. PCR- SBT has proved to be the most useful method for exploring the allelic polymorphism in DQA1 gene in zebu and its crossbred cattle in our study. Further use of this technique is equally appropriate for all kinds of traits i.e. production, reproduction and growth type of traits and beneficial for establishing new breeding objectives

Genomic selection in sheep: Prospects for Indian sheep industry

Small ruminants are the key component among the livestock sector that plays a significant role in sustainable livelihood of landless and small holder farmers in India. Rural human population constitutes 72.22 % out of which majority are dependent directly or indirectly on the agriculture and livestock related occupations. The total sheep in the country is 65.06 million that accounts for nearly 12.7% of total livestock population in India.Traditional breeding programs aimed at improving the productivity of sheep through selection. Nevertheless accurate, this approach always relied upon the intensity of selection and length of the generation interval (GI). Larger the GI, more time it took to improve any given trait of interest. Since advent of the genomic selection, genomic estimated breeding values (GEBV) of animals are being obtained at juvenile stage. This has resulted in significant reduction in the generation interval and faster rate of genetic improvement with more accuracy. Single Step approach has further allowed use of even non-genotyped individuals in reference for better accuracy and less bias of prediction. Genomic selection has literally replaced the pedigree selection at many places across the world barring India. In our country given the large population, sheep breeds can be easily brought under the genetic improvement programs and hence the benefits to the sheep industry can be increased many-fold. In India, given large sheep genetic resources which are yet to be included in the improvement programs due to lack of pedigree relationship can be very well brought under this umbrella. Genomic selection can be effectively used to enhance the pace and accuracy of selection programs especially for the traits which are difficult to measure, expressed in one sex and late in life or post death and have low heritability

Evaluation of factors affecting growth performance of Avikalin sheep

Not AvailableNot AvailableNot Availabl

Estimates of co(variance) component and genetics parameters for growth traits in Avikalin sheep

Not Available(Co)variance components and genetic parameters for various growth traits of Avikalin sheep maintained at Central Sheep and Wool Research Institute, Avikanagar, Rajasthan, India, were estimated by Restricted Maximum Likelihood, fitting six animal models with various combinations of direct and maternal effects. Records of 3,840 animals descended from 257 sires and 1,194 dams were taken for this study over a period of 32 years (1977–2008). Direct heritability estimates (from best model as per likelihood ratio test) for weight at birth, weaning, 6 and 12 months of age, and average daily gain from birth to weaning, weaning to 6 months, and 6 to 12 months were 0.28 ± 0.03, 0.20 ± 0.03, 0.28 ± 0.07, 0.15 ± 0.04, 0.21 ± 0.03, 0.16 and 0.03 ± 0.03, respectively. Maternal heritability for traits declined as animal grows older and it was not at all evident at adult age and for post-weaning daily gain. Maternal permanent environmental effect (c 2) declined significantly with advancement of age of animal. A small effect of c 2 on post-weaning weights was probably a carryover effect of pre-weaning maternal influence. A significant large negative genetic correlation was observed between direct and maternal genetic effects for all the traits, indicating antagonistic pleiotropy, which needs special care while formulating breeding plans. A fair rate of genetic progress seems possible in the flock by selection for all traits, but direct and maternal genetic correlation needs to be taken in to consideration.Not Availabl

Not Available

Not AvailableThe objective of this study was to assess the genetic diversity of the Sirohi goat for DRB and DQB1 loci, and to study their association with antibody response induced by the Peste des petits ruminants (PPR) vaccine. A total of 360 Sirohi kids were studied using single stranded confirmation polymorphism (SSCP) followed by polymerase chain reaction sequence-based typing (PCR-SBT) for DRB and DQB1 diversities. The competitive enzyme-linked immuno-sorbent assay (C-ELISA) was used to evaluate immune response post-PPR vaccination. Study revealed rich diversity of major histocompatibility complex (MHC) region in goat. A total of 18 DRB and 15 DQB1 alleles were obtained which were new. Alleles DRB*0104 and DQB1*0101 were the most common. The approach of SSCP combined with PCR-SBT reflects cost-effective and most powerful approach to decipher the genetic diversity in complex MHC region. Study revealed variation in DRB and DQB1 genes in Sirohi flock along with high Wu–Kabat index. A total of 16 of the 89 amino acid residue sites in DRB and 19 of 86 residue sites in DQB1 had more than three amino acid substitutions. Positive evolutionary selection was evident in Sirohi for MHC region. Nonsignificant association of DRB and DQB1 genotypes with PPR virus (PPRV) vaccine response revealed complexity of the phenotype and importance of other factors for vaccine response. Rich diversity of DRB and DQB1 genes reflects the fitness of the population and importance of this locus for future selection programmes.Not Availabl

Not Available

Not AvailableLamb survival till first 28 days of life is critical as it increases the chances of economic gain in flock. Objective of the current study was to assess the incidence of neonatal mortality in lambs born in arid region of India and genetic and non-genetic factors affecting it. The present study was conducted using the data on 4,137 Magra and 4,595 Marwari sheep over 17 years (1999 to 2016). Incidence of neonatal mortality was very low in Magra (1.04%) and Marwari (2.48%) sheep, respectively in semi-intensive management system. Year and seasonal variation was observed for neonatal losses. Males had lower odds of survival as compared to females. Odds of survival were low if the lambs were born to dams of low body weight and in their first parity. It was observed that the lamb survival can be improved if due care of the lambs born with low birth weight (<2 kg) is taken. The heritability estimate was moderate in Magra sheep (0.17), indicating further scope for genetic improvement for lamb survival through selection. However, for Marwari sheep, the total heritability was 0.02, thus limiting the scope for selection. Arid region favoured the lamb survival. Hardiness of the Magra and Marwari sheep, their high lamb survival along with standard production potential is indicative of the good genetics of these sheep along with better management practices adopted at arid regional campus, thus reflecting better sheep welfare practices.ICAR-All India Network Programme on Neonatal Mortality in Farm Animal

Associations between polymorphisms of LAP3 and SIRT1 genes with clinical mastitis and milk production traits in Sahiwal and Karan Fries dairy cattle

Abstract Background Bovine mastitis continues to remain as the most challenging disease in dairy cattle, as a result improvement of selection methods has great economic relevance while a deeper understanding of the genetic mechanisms regulating milk production traits and mastitis is of general scientific interest. Objectives This study aimed to evaluate the association of SNPs of the LAP3 and SIRT1 genes with estimated breeding values (EBVs) of milk production traits and clinical mastitis in dairy cattle of Indian origin. Methods DNA samples from 263 animals (Sahiwal and Karan Fries cattle) were genotyped by PCR‐RFLP to assess their pattern of genetic variation. EBVs of milk production traits and phenotypic records of incidences of clinical mastitis were used for association analysis. Results A total of 9 SNPs were identified, including three (rs110932626: A>G, rs716493845: C>T and rs43702363: C>T) in intron 12, four (g.24904G>C, rs110839532: G>T, rs43702361: T>C and rs41255599: C>T) in exon 13 and within 3’UTR of LAP3 gene and two (rs110250233: G>A and rs42140046: C>G) in the promoter region of SIRT1 gene. Eight of these identified SNPs were chosen for subsequent genotyping and association analyses. Association analysis revealed that SNP rs41255599: C>T was significantly associated with lactation milk yield, 305‐day milk yield, 305‐day fat yield, 305‐day solid not fat yield, lactation length and incidence of clinical mastitis (p G and rs43702363: C>T showed significant association with 305‐day milk yield. Conclusion Overall, these findings provide evidence for association of the LAP3 gene with milk production traits and clinical mastitis in dairy cattle, indicating the potential role of LAP3 variants in these traits