Anti-Müllerian hormone as an endocrine biomarker of reproductive longevity and assessment of single nucleotide polymorphisms in AMH gene of Bos indicus breeds of cattle.

Anti-Müllerian hormone (AMH) is a member of the TGF-ß superfamily produced by follicular granulosa cells in women and cattle and is considered an endocrine biomarker of ovarian follicular reserve. The study examined how age and parity influence serum AMH concentration and investigated the presence of single nucleotide polymorphisms in AMH gene in Bos indicus breeds viz Malnad Gidda Amritmahal and Hallikar. All five exons of AMH gene amplified by polymerase chain reaction were subjected to sanger sequencing and identified important SNP and its effects. We observed a highly significant relationship between parity and AMH concentration in Amritmahal cattle, whereas Malnad Gidda and Hallikar breeds did not show a significant difference. We identified one SNP located in exon 5 (rs21402788) with base change A>G, a non-synonymous mutation resulting in a change in amino acid Q>R and the protein product. It is concluded that AMH level could be considered as an indicator of the ovarian reserve and productive herd life (longevity) irrespective of age/parity, especially in B. indicus breeds of cattle.

Sperm Transcripts Associated With Odorant Binding and Olfactory Transduction Pathways Are Altered in Breeding Bulls Producing Poor-Quality Semen.

Spermatozoa carries a reservoir of mRNAs regulating sperm functions and fertilizing potential. Although it is well recognized that a considerable proportion of high genetic merit breeding bulls produce poor-quality semen, the transcriptomic alterations in spermatozoa from such bulls are not understood. In the present study, comparative high-throughput transcriptomic profiling of spermatozoa from good and poor-quality semen-producing bulls was carried out to identify the transcripts associated with semen quality. Using next-generation sequencing (NGS), we identified 11,632 transcripts in Holstein Friesian bull spermatozoa; after total hit normalization, a total of 544 transcripts were detected, of which 185 transcripts were common to both good and poor-quality semen, while 181 sperm transcripts were unique to good quality semen, and 178 transcripts were unique to poor-quality semen. Among the co-expressed transcripts, 31 were upregulated, while 108 were downregulated, and 46 were neutrally expressed in poor-quality semen. Bioinformatics analysis revealed that the dysregulated transcripts were predominantly involved in molecular function, such as olfactory receptor activity and odor binding, and in biological process, such as detection of chemical stimulus involved in sensory perception, sensory perception of smell, signal transduction, and signal synaptic transmission. Since a majority of the dysregulated transcripts were involved in the olfactory pathway (85% of enriched dysregulated genes were involved in this pathway), the expression of selected five transcripts associated with this pathway (OR2T11, OR10S1, ORIL3, OR5M11, and PRRX1) were validated using real-time qPCR, and it was found that their transcriptional abundance followed the same trend as observed in NGS; the sperm transcriptional abundance of OR2T11 and OR10S1 differed significantly (p < 0.05) between good and poor-quality semen. It is concluded that poor-quality semen showed altered expression of transcripts associated with olfactory receptors and pathways indicating the relationship between olfactory pathway and semen quality in bulls.

Luteinizing hormone beta gene polymorphism and its effect on semen quality traits and luteinizing hormone concentrations in Murrah buffalo bulls.

OBJECTIVE: Present investigation was aimed to study the Single Nucleotide Variants of the luteinizing hormone beta (LHß) gene and to analyze their association with the semen quality (fresh and post-thawed frozen semen) and luteinizing hormone (LH) concentrations in Murrah buffalo bulls. METHODS: Polymerase chain reaction-single stranded conformational polymorphism (PCR-SSCP) and Sanger sequencing method is used to study genetic variability in LHß gene. LH assay was carried out using enzyme-linked immunosorbent assay method. A fixed general linear model was used to analyze association of single nucleotide polymorphism (SNP) of LHß gene with semen quality in 109 and LH concentrations in 80 Murrah bulls. RESULTS: LHß gene was found to be polymorphic. Total six SNPs were identified in LHß gene g C356090A, g C356113T, g A356701G, g G355869A, g G356330C, and g G356606T. Single Stranded Conformational Polymorphism variants of pattern 2 of exon 1+pattern 2 of exon 2+pattern 1 of exon 3 had highly significant (p<0.01) effect on sperm concentration (million/mL), percent mass motility, acrosome integrity and membrane integrity in fresh and frozen semen whereas significant (p<0.05) effect was observed on percent live spermatozoa. SSCP variants of pattern 2 of exon 1+pattern 2 of exon 2+pattern 1 of exon 3 had highly significant (p<0.01) effect on luteinizing hormone concentrations too. CONCLUSION: The observed association between SSCP variants of LHß gene with semen quality parameters and LH concentrations indicated the possibilities of using LHß as a candidate gene for identification of markers for semen quality traits and LH concentrations in Murrah buffaloes.