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Black Bengal goats are an interesting genetic material to underpin the genetic mechanism of reproduction due to high prolificacy and sexual precocity. In the present study, novel SNPs in BMPR1B, BMP15 and GDF9 genes were genotyped to evaluate their association with the reproductive traits. PCR-RFLP and Tetra primer ARMS-PCR based protocols were developed for genotyping the six novel SNPs viz. T(-242)C in BMPR1B , G735A and C808G in BMP15 and C818T, A959C and G1189A in GDF9 . Linear mixed model for association of these SNPs with litter size and linear fix model for other traits were employed. The effect of season and parity was highly significant ( p ≤ 0.01) on litter size which varied with change in locus combination. However, there was no significant effect of genotype and year of birth on the litter size. Similarly, age at first heat, age at first service and age at first kidding were not affected by the year of birth as well as the genotype. Season of kidding did not affect the age at first heat and age at first service. However, significant ( p ≤ 0.05) association was observed between the season of kidding and the age at first kidding. The regression of age at sexual maturity on the age at first service and regression of age at first service on the age at first kidding was highly significant ( P ≤ 0.01). Further studies involving more number of breeds as well as animals may be fruitful for exploring the association of novel SNPs with caprine reproductive traits. [ABSTRACT FROM AUTHOR]

Reproductive traits are extremely important to the goat industry because moderate increase in litter size can lead to large profit. Traditional selection for improving litter size is difficult due to sex-limited nature and low heritability of the trait (5–10%). In addition, the lack of knowledge on the number of the genes controlling this trait and the possible gene interactions are the other limitations for this trait. Molecular genetics can overcome these limitations offering new opportunities for the improvement of reproductive traits, as it supplies tools to analyze genetic variability directly at the DNA level with the possibility of detecting the individual genes influencing the reproductive capability. For the last decade, molecular genetics has led to the discovery of individual genes or candidate genes with substantial effects on the reproductive trait viz. BMPR1B , GDF9 , BMP15 , FSHβ , FSHR , POU1F1 , PRLR , KiSS-1 , GPR54 , GH , INH , CART , GnRH , GnRHR , LHβ , BMP4 , KITLG , MT2 , CYP21 and AA-NAT . Despite the progress made in goat fecundity studies, it's hard to satisfy the actual application because the reproductive traits are complex quantitative traits involving multiple genes, loci and interactions. So it is important to analyze the combined effect of multiple genes or loci on reproductive traits. Little progress has been made on understanding interaction between genes, gene and environment, and genetic effect analysis. Thus the need of the hour is to identify more functional genes, clarify molecular mechanism of action and regulatory network and to resort to more holistic approaches like genomic selection which can tremendously accelerate the goat improvement. [ABSTRACT FROM AUTHOR]

Abstract: Genetic variation at 25 microsatellite loci, population structure, and genetic bottleneck hypothesis were examined in Marwari goats in the arid region of Rajasthan (India). The estimates of genetic variability such as effective number of alleles and gene diversities frequently observed in microsatellite markers revealed substantial genetic variation. The average polymorphism across the studied loci and the expected gene diversity in the population were 1.295 and 0.623±0.041, respectively. The population was observed to be significantly differentiated into groups, and showed a fairly high level of inbreeding (f =0.264±0.046) and global heterozygote deficit. The bottleneck analysis indicated the introduction of unique/rare alleles by the immigrants. The study revealed that Marwari goats need appropriate genetic management for their conservation and improvement under harsh climatic conditions of the arid zone. The information generated in this study may further be utilized for studying differentiation and relationships among different Indian goat breeds. [Copyright &y& Elsevier]

Abstract: Genetic variation at 23 microsatellite loci, population structure, and genetic bottleneck hypothesis were examined for Jamunapari goat population found in Etawah, Uttar Pradesh, India. Estimates of genetic variability such as effective number of alleles and gene diversities revealed substantial genetic variation frequently displayed by microsatellite markers. Number of alleles observed across the microsatellite loci varied from 2 to 10 with an overall mean of 4.913±1.905. Average polymorphism across the studied loci and expected gene diversity in the population were 1.066±0.510 and 0.528±0.237, respectively. Population was observed to be significantly differentiated into different groups, and showed fairly high level of inbreeding (f =0.189±0.049) and global heterozygote deficit. Bottleneck analysis indicated the introduction of unique/rare alleles by immigrants. [Copyright &y& Elsevier]