Gene expression profiles of Day 30 embryos from diet-restricted sows
Ontology highlight
ABSTRACT: In our previous sow study, two subpopulations of feed-restricted sows (60% of anticipated feed intake) were identified: ‘Restrict (Risk)’ that mobilized higher levels of body tissue stores (>40MJ ME day-1) compared to ‘Restrict (Non-Risk)’ sows (Patterson et al. Reprod. Fert. Deveopl., 2011, 23, 889-898) and although Risk sows maintain higher litter growth in the weaned litter, this was at the expense of lower embryonic weight in their subsequent litter compared with Non-Risk sows. To understand the underlying molecular mechanisms involved, we investigated the gene expression profiles of embryos from Risk and Non-Risk litters in this experiment. Two-condition experiment, Risk vs Non Risk. Biological replicates: 20 risk, 20non-risk, independently compared to reference (all the 80 samples pooled from ch 1).
Project description:In our previous sow study, two subpopulations of feed-restricted sows (60% of anticipated feed intake) were identified: ‘Restrict (Risk)’ that mobilized higher levels of body tissue stores (>40MJ ME day-1) compared to ‘Restrict (Non-Risk)’ sows (Patterson et al. Reprod. Fert. Deveopl., 2011, 23, 889-898) and although Risk sows maintain higher litter growth in the weaned litter, this was at the expense of lower embryonic weight in their subsequent litter compared with Non-Risk sows. To understand the underlying molecular mechanisms involved, we investigated the gene expression profiles of embryos from Risk and Non-Risk litters in this experiment.
Project description:The objective of modern pig breeding is to exhaust the genetic potential in reproduction performance of sows regarding to litter size and litter weight of piglets. During gestation period, umbilical cord contributes to placenta-fetal communication and plays an indispensable role in the intrauterine embryonic development. In this study, we attempted to analyze the molecular mechanism of reproductive declined in high-parity sows from the perspective of umbilical cord blood. Firstly, we analyzed the reproductive character data of sows, and then the histological analysis of umbilical cord phenotype was performed. Next, we evaluated the effect of umbilical cord blood exosomes (UCB-EXO) on angiogenesis. Moreover, the expression characteristics of miRNA in UCB-EXO of high-parity sows with poor reproductive performance (OS) and multiparous sows with excellent reproductive performance (MS) were analyzed. Results showed that the reproductive performance performed best at 3rd-7th and gradually decreased after 8th parities. Angiogenesis was repressed in OS piglets. Moreover, the Exo-MS exhibited pro-angiogenesis properties, with those of Exo-OS were diminished. With the increase of parities, the angiogenesis and immune function of sows decreased significantly, greatly limited the reproductive potential of sows. The data demonstrated that miRNAs of UCB-EXO played a central role in intrauterine development and suggested a novel possible explanation for reproductive potential, provides reference for increasing female reproductive efficiency.
Project description:To identify the molecular markers of early pregnancy in pigs, we compared global gene expression profiles of the maternal peripheral blood in pregnant sows with the non-pregnant sows. Peripheral blood sample was collected at 14 days after insemination from the submandibular vein of pregnant and non-pregnant sows respectively, and total RNA was isolated, purified and sent for microarray analysis. This study identified 127 up-regulated and 56 down-regulated genes (FC >= 1.5 and P < 0.05) in peripheral blood from pregnant sows versus non-pregnant sows. Of the differently expressed genes, nine (including LPAR3, RXFP4, GALP, CBR1, CBR2, GPX6, USP18, LHB and NR5A1) were found to exert function related to early pregnancy processes. Seven differentially expressed genes (CHGB, USP18, VWF, LPAR3, NR5A1, PPARD, BIN1) were selected to perform qRT-PCR in the same RNA samples.The expression profiles of these genes detected by qRT-PCR were consistent with those by microarray, which confirmed the reliability of our microarray data.
Project description:Previous results from a genome scan in a F2 Iberian by Meishan intercross showed several chromosome regions associated with litter size traits. In order to identify candidate genes underlying these QTL we have performed an ovary gene expression analysis during pregnancy. F2 sows were ranked by their estimated breeding values for prolificacy, the six sows with higher EBV (HIGH prolificacy) and the six with lower EBV (LOW prolificacy) were selected. Samples were hybridized to Affymetrix porcine expression microarrays. The statistical analysis with a mixed-model approach identified 221 differentially expressed probes, representing 189 genes. These genes were functionally annotated in order to identify the genetic pathways overrepresented. Among the most represented functional groups the first one was immune system response activation against external stimulus. The second group was made up of genes which regulate the maternal homeostasis by complement and coagulation cascades. The last group was involved on lipid and fatty acid enzymes of metabolic processes, which participate in steroidogenesis pathway. In order to identify powerful candidate genes for prolificacy, the second approach of this study was merging microarray data with position information of QTL affecting litter size, previously detected in the same experimental cross. According to this, we have identified 27 differentially expressed genes co-localized with QTL for litter size traits, which fulfill the biological, positional and functional criteria. Twelve ovary samples: six high prolific sows and low prolific sows, slaughtered after 30 days of pregnancy. Each sample is the average between right and left ovary from each sow.
Project description:Previous results from a genome scan in a F2 Iberian by Meishan intercross showed several chromosome regions associated with litter size traits. In order to identify candidate genes underlying these QTL we have performed an ovary gene expression analysis during pregnancy. F2 sows were ranked by their estimated breeding values for prolificacy, the six sows with higher EBV (HIGH prolificacy) and the six with lower EBV (LOW prolificacy) were selected. Samples were hybridized to Affymetrix porcine expression microarrays. The statistical analysis with a mixed-model approach identified 221 differentially expressed probes, representing 189 genes. These genes were functionally annotated in order to identify the genetic pathways overrepresented. Among the most represented functional groups the first one was immune system response activation against external stimulus. The second group was made up of genes which regulate the maternal homeostasis by complement and coagulation cascades. The last group was involved on lipid and fatty acid enzymes of metabolic processes, which participate in steroidogenesis pathway. In order to identify powerful candidate genes for prolificacy, the second approach of this study was merging microarray data with position information of QTL affecting litter size, previously detected in the same experimental cross. According to this, we have identified 27 differentially expressed genes co-localized with QTL for litter size traits, which fulfill the biological, positional and functional criteria.
Project description:Primiparous sows were randomly allocated to two treatments and were separated from piglets 8h daily from Day 21 of lactation companied with daily boar exposure for oestrus detection until weaning (Day 28). Gene expression of Day 9 embryos were compared between control sows (FE; sows artificially inseminated when in heat during lactation ) and Skip-a-Heat sows (SE; sows in heat during lactation and artificially inseminated on the following oestrus cycle). Stimulating lactational oestrus then two mating strategies were applied to primiparous sows; 1)FE; sows were in heat during lactation and received artificial insemination) and Skip-a-Heat sows (SE; sows were in heat during lactation and received artificial insemination at fallowing oestrus cycle).
Project description:Blood immune cells transcriptome can be used as a tool to investigate molecular mechanisms or identify biomarkers of several physiological processes. Factors such as reproductive status, age, or physical and mental states resulting from social and non-social environmental aspects can influence the activation and phenotype of immune cells. Here we describe the gene expression levels in peripheral blood mononuclear cells (PBMC) of multiparous sows of various parity ranks housed during gestation in a stable social group either in a conventional environment on a slatted concrete floor (C) or in an enriched environment with deep straw litter and a bigger space allowance (E).
Project description:Embryonic survival rate is an important factor for the fecundity of sows, and it is affected by endometrium secreting histotroph. A higher concentration of calcium ion has been observed in the uterus of the high prolific Erhualian sows (EH) compared with low prolific ones (EL), which suggests EH sows had a greater establishment and maintenance of pregnancy, and thus increase embryonic survival rate during peri-implantation period. In order to understand the mechanisms of endometrium secreting histotroph affecting embryonic survival rate during Erhualian peri-implantation period, the expression patterns of endometrial mRNA in the EH and EL on day 12 of gestation were analyzed using RNA sequencing technology. 164 differentially expressed genes (DEGs) were identified (Padj < 0.05, |log2(FC)| ≥ 1),including 46 upregulated and 118 downregulated genes in the EH group compared with EL group. Among these DEGs, 17 DEGs have been previously reported as DEGs in other pig breeds for litter size. Gene Ontology (GO) enrichment indicated that a subset of DEGs were involved in the calcium ion binding and cell adhesion. Solute carrier family 8 member A3 (SLC8A3) and solute carrier family 24 member 4 (SLC24A4) were upregulated genes (Padj < 0.05) in EH group and they were considered as key candidate genes expressed in endometrium to affect embryonic survival rate during peri-implantation period. The present results will aid in understanding the variation of litter size in Erhualian breed during peri-implantation period.
Project description:Prolificacy related traits are of great economical interest in the pig industry. microRNAs (miRNAs) are post-transcriptional regulators of gene expression important for reproductive processes. In pigs, the roles of ovarian miRNAs during gestation remain unknown although the ovaries are essential during gestation. It has been hypothesised that ovarian miRNAs could participate during the porcine gestation and, moreover, they could influence the prolificacy levels of sows. The miRNA expression profile was compared in the ovaries of pregnant Iberian x Meishan F2 sows displaying extreme phenotypes regarding prolificacy levels defined as the number of embryos (NE) attached to the uterus at 30-32 days of gestation. miR-146a-5p and miR-142-3p were differentially expressed between high (NE≥13) and low (NE≤11) prolificacy sows. In silico functional analyses of the predicted mRNA targets for these miRNAs revealed that miR-146a-5p targets were mainly involved in the immune system response important for the establishment of the maternal-foetal tolerance, implantation and maintenance of pregnancy. On the other hand, miR-142-3p targets participated in different biological processes that would contribute to the homeostasis maintenance to ensure a correct functional development of the ovaries. miRNAs associated with prolificacy levels could regulate negatively, by a novel post-transcriptional mechanism, their predicted mRNA targets, PPM1K, TLR1 and CPEB2 which have been reported as differentially expressed in the ovaries of pregnant sows regarding the prolificacy levels. Furthermore, among predicted mRNA targets for miRNAs associated with prolificacy, four genes, differentially expressed in the ovaries of pregnant sows regarding prolificacy levels, (LRRK1, BAT1, CPEB2, CCL8) are proposed to be good candidate genes for litter size due to their location within confidence intervals for prolificacy QTL described previously. Overall, it is suggested that the up-regulation of miR-146a-5p and miR-142-3p in the ovaries of pregnant sows could help in the establishment of a uterine environment, which would favor the embryonic development.
Project description:This study provide an opportunity to elucidate the genetic control of fetal implantation and improve our understanding of fetal implantation and gestation maintenance, thus make further improvement for litter size of pigs. Nine pregnant sows were slaughtered by electrical on day 13, day 18 and day 24 after insemination (the pregnant group, three sows every period). The non-pregnant sows were slaughtered on day 13 after inseminated (n=3).In pregnant sows, samples of the endometrium attachment sites and inter-sites were taken. Samples from the endometrium of the non-pregnant sows were taken from comparable locations.