Effect of COQ9 and STAT5A polymorphisms on reproductive performance in a Holstein cow herd in Mexico

Study of milk production genes and their association with production traits in Rathi cattle

The study aimed to identify polymorphism of LEP, and STAT5A milk-producing genes and their association with production traits in Rathi cattle. An overall 160 animals were selected from a population of Rathi cattle from Livestock Research Station, Rajasthan University of Veterinary and Animals Sciences, Bikaner (Rajasthan). The phenotypic information on total milk yield, peak yield and lactation length were recorded from the years 2012- 2018. Each animal’s milk sample (100 ml) was analysed for milk composition parameters. Genomic DNA was extracted from the whole blood sample through the spin column method and association analysis was done. The polymorphism have been observed in exon-3 (454 bp) of LEP gene, intron 9-10 (224 bp) and intron-15-exon-16 (379 bp) of STAT5A genes by PCR-SSCP and revealed two types of genotypic pattern. The STAT5A exon-7 (215 bp) also showed polymorphism with three genotypic patterns. The AB pattern of LEP exon-3 and AA pattern of intron 9-10 and intron-15-exon-16 of STAT5A genes showed a significant effect on total milk yield. The BB genotypic pattern of the STAT5A exon-7 gene showed a significant impact on peak yield. The AB pattern of LEP and STAT5A genes were associated with more milk fat % in the studied population of Rathi cattle. All these genes showed a significant effect on total solids. The association analysis of LEP and STAT5A genes with different milk production and milk composition traits illustrated the worth of these genes for marker-assisted selection of dairy cattle. Thus, the present study was designed to unmask the relevant genetic factors responsible for variation in milk performance traits.

Network analysis reveals different hub genes and molecular pathways for pig in vitro fertilized early embryos and parthenogenotes

Maternal-to-zygotic transition (MZT) occurs when maternal transcripts decay and zygotic genome is activated gradually at early stage of embryo development. Previously, single cell RNA-seq (scRNA-seq) has helped us to uncover the MZT-associated mRNA dynamics of in vitro produced pig early embryos. Here, to further investigate functional modules and hub genes associated with MZT process, the weighted gene-coexpression network analysis (WGCNA) was performed on our previously generated 45 scRNA-seq datasets. For the in vitro fertilized embryo (IVF) group, 5 significant modules were identified (midnightblue/black/red and blue/brown modules, positively correlated with 1-cell (IVF1) and 8-cell (IVF8), respectively), containing genes mainly enriched in signaling pathways such as Wnt, regulation of RNA transcription, fatty acid metabolic process, poly(A) RNA binding and lysosome. For the parthenogenetically activated embryo (PA) group, 9 significant modules were identified (black/purple/red, brown/turquoise/yellow, and magenta/blue/green modules, positively correlated with MII oocytes, 1-cell (PA1), and 8-cell (PA8), respectively), mainly enriched in extracellular exosome, poly(A) RNA binding, mitochondrion, transcription factor activity. Moreover, some of identified hub genes within 3 IVF and 9 PA significant modules, including ADCY2, DHX34, KDM4A, GDF10, ABCC10, PAFAH2, HEXIM2, COQ9, DCAF11, SGK1, ESRRB etc., have been reported to play vital roles in different biological processes. Our findings provide information and resources for subsequent in-depth study on the regulation and function of MZT in pig embryos.

Association between somatotropic axis gene polymorphisms and reproductive efficiency of bovine females: a review

Abstract Reproductive characteristics directly reflect on productive performance, as they determine the number of calves born annually and the interval between generations, thereby affecting the selection intensity. This allows for the determination of the most important economic variables that directly affect the production system. The present study is a literature review of somatotropic axis gene polymorphisms that are associated with reproductive functions in heifers and cows (Bos taurus taurus and Bos taurus indicus). The following characteristics were analyzed from the various studies reviewed: number of services per pregnancy (Nº services/ pregnancy), age at first calving (AFC), calving interval (CI), and period of service calving conception interval (CCI). The research was conducted during the period from 2011 to 2021, and associations were found among all indicators of reproductive efficiency evaluated in heifers and cows, with 27 single nucleotide polymorphisms (SNPs): 18 in GHR, 5 in IGF-I, and 4 in STAT5A. This study revealed the relationships between SNPs and the reproductive efficiency indicators and demonstrated that molecular genetic techniques enhance the animal selection process, resulting in more profitable systems that are sustainable in the long term.

Associação entre polimorfismos de genes do eixo somatotrópico e eficiência reprodutiva de fêmeas bovinas: revisão de literatura

Resumo Características reprodutivas refletem diretamente no desempenho produtivo visto que são capazes de determinar o número de bezerros nascidos anualmente, além de afetar o intervalo entre gerações e, consequentemente, a intensidade de seleção, fazendo com o que tais atributos sejam apontados como variáveis econômicas das mais importantes que afetam diretamente o sistema de produção. O presente estudo propõe realizar uma revisão de literatura de polimorfismos de genes do eixo somatotrópico associados a funções reprodutivas em novilhas e vacas (Bos taurus taurus e Bos taurus indicus), indicadas pelos índices: número de serviços por gestação (Nº serviços/gestação), idade ao primeiro parto (IPP), intervalo de partos (IP) e período de serviço, como também denominado de intervalo parto-concepção (IPC). As pesquisas encontradas durante o período de 2011 a 2021 demonstraram associações entre todos os indicadores de eficiência reprodutiva analisados de novilhas e vacas com 27 polimorfismos de nucleotídeo único (SNPs), sendo 18 em GHR, 5 em IGF-I e 4 em STAT5A. Dessa forma, este estudo mostrou relação entre os SNPs e os indicadores de eficiência reprodutiva, demonstrando que técnicas de genética molecular potencializam o processo de seleção dos animais, resultando em sistemas mais lucrativos e que se sustentam a longo prazo.