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Background: Neuropeptide Y (NPY), a 36-AA neurotransmitter involved in the control of appetite, feeding and energy homeostasis. The bovine NPY gene is located on chromosome 4 and consists of four exons. Earlier studies have reported that genes involved in feed intake regulation, energy production and energy regulation may affect different growth and production traits in cattle. Information associating NPY SNP to reproduction and production traits in dairy cattle is, however, limited. Hence, the present study was planned to explore SNPs in NPY gene and its possible association with reproduction and first lactation production traits in Sahiwal cattle. Methodology: DNA samples were isolated from blood that has collected from hundred and three Sahiwal cows. Three regions of NPY were amplified using designed primer pairs. The sequencing of the targeted regions was done in 103 Sahiwal cows. Least squares analysis of variance was carried out for unequal and non-orthogonal data using the technique described by Harvey (1990) to study effect of non-genetic factors. Significance of differences based on genotypes effect of growth, reproduction and production traits were tested by general linear models. Result: Sequence data analysis revealed two transversions in NPY gene. For these identified nucleotide variations, positions were A72073973C (intron 3) and C72068620A (intron 3). This is the first report of the presence of NPY gene polymorphism in purebred Bos indicus of Indian origin. For SNP A72073973C, performances of animals with homozygote AA genotype exhibited significantly higher milk production (P≤0.01) and growth performance (P≤0.05) than heterozygote genotype. Heterozygous genotype exhibited superior performance for the SNP C72068620A which was found to be significantly associated (P£0.05) with 18M wt, WFS, WFC, FCI and FL305DMY.

Background: Loss of genetic diversity is allied with adverse incidents such as inbreeding depression in fitness related traits, addiction of favorable alleles and enhances fluctuation on selection response. Therefore, the study aims to monitor population structure and avoid unfavorable effects of inbreeding for sustainable improvement in breeding programme.Methods: Pedigree information on 3449 animals born from 1955-2018 was analyzed. The effect on inbreeding on Age at first calving (AFC), Service period (SP), Daughter pregnancy rate (DPR), Calving interval (CI) and pregnancy rate was seen by regression analysis.Result: The pedigree completeness index (PCI) were found to be (%) 92.32, 80.26, 65.22, 49.43% and 32.54 respectively from first to fifth generations. The estimated average inbreeding rate was 2.30% and average genetic diversity loss was 2.64%. Study also revealed significant effect of inbreeding on (AFC, CI and SP) with slightly increasing trends. Hence, it is suggested that more precise pedigree recording and planned mating strategies should be adopted to avoid negative effect of inbreeding in future generation.

Background: A population is continuously facing the changing environment and its directly influencing the production of animal so to adopt these changes population must be flexible and have sufficient variability to overcome the adverse affects of environment. The evaluation of animals in terms of production performance traits along with impact of inbreeding coefficient is essential to formulate breeding and selection strategies for higher genetic improvement. Methods: Genealogy data of 6429 animals maintained at ICAR-NDRI, Karnal, India was analyzed by web-based POPREP application tool (http:// poprep.tzv.fal.de) and ENDOG V5.8 used to study the population structure and genetic diversity and regression model to study the effect of inbreeding on first lactation productive traits in Murrah buffaloes. Result: The result indicated that 91.91% of the individuals had known pedigree. The maximum generation traced was 13 with mean, full and equivalent complete generation as 5.93, 1.67 and 3.25 respectively. The average generation interval was 8.28 years and longer for the sire-son pathway and 2.16% was average inbreeding in whole population. The average genetic diversity loss was 2.10% indicated that the population has been stable with sufficient diversity. The study also revealed non significant effect of inbreeding on all first lactation traits. The low inbreeding was firstly due to introduction of new genetic variant and culling of animals avoiding mating of related ones and secondly due to incompleteness of pedigree in earlier years. This can be used as a base line information of phenomic needs to be generated before applying genomics tools in particular herd to be used as reference population in future for genomic selection.

Bull fertility is an important component of reproductive efficiency in dairy cattle. PPP1R11 is a potent candidate gene for bull fertility being involved in the pathway of spermatogenesis. Present investigation was carried out in twenty Karan Fries (KF) bull to identify SNPs of PPP1R11 gene and their association with conception rate. Genomic DNA was extracted from frozen semen straws by phenol-chloroform method. Primer pair targeted to exonic II region of PPP1R11 gene was designed using Primer 3.1 software. PCR reactions were carried out in thermal cycler after optimizing. The PCR product was checked on 1.5% horizontal agarose gel electrophoresis to verify the amplification of target region. Samples were sequenced and SNPs were identified using multiple alignment programme with respect to reference sequence and visual inspection of chromatograms. Sequencing results revealed only two SNPs [G28708846A, T28708860C] at exonic II region of PPP1R11 gene in KF bulls. Each bull was genotyped with respect to each of the two identified SNPs. Association of SNP genotype with conception rate was analyzed using least square ANOVA taking genotypes as fixed effect. The result indicated that, only one SNP [T28708860C] had significant (p>0.01) effect on conception rate. The bulls with TT genotype revealed significantly (p>0.01) highest conception rate (53.20±2.96%) followed by bulls with TC (43.12±2.39%) and the lowest in bulls with CC (34.59± 2.28%) genotypes. The results of present finding suggested that association of SNPs with conception rate after validation on large population might be useful in marker assisted selection for selection of bull with high fertility in future.