Diversity and community pattern of sulfate-reducing bacteria in piglet gut.
ABSTRACT: Background:Among the gut microbiota, sulfate-reducing bacteria (SRB) is a kind of hydrogen-utilizing functional bacteria that plays an important role in intestinal hydrogen and sulfur metabolism. However, information is lacking regarding diversity and community structure of SRB in the gut of piglets. Middle cecum contents were collected from 6 Yorkshire and 6 Meishan piglets at postnatal days (PND) 14, 28 and 49. Piglets were weaned at PND28. Real-time quantitative PCR was performed to detect the number of SRB in the cecum based on dissimilatory sulfite reductase subunit A (dsrA) gene. Prior to real-time PCR, plasmid containing the dsrA gene was constructed and used as external standard to create a standard curve, from which the gene copies of dsrA were calculated. H2S concentration in the cecal contents was measured. Illumina PE250 sequencing of dsrA gene was used to investigate SRB diversity in cecum contents. Results:The qPCR results showed that the number of SRB at PND49 was significantly higher than that at PND28 in Meishan piglets. The concentration of H2S has no significant difference between piglet breeds and between different ages. The Illumina sequencing analysis revealed that the Chao1 richness index was significantly higher at PND49 than that at PND14 and PND28 in Yorkshire piglets. Based on dsrA gene similarities, Proteobacteria, Actinobacteria, and Firmicutes were identified at the phylum level, and most sequences were classified as Proteobacteria. At the genus level, most of sequences were classified as Desulfovibrio. At the species level, Desulfovibrio intestinalis was the predominant SRB in the piglet cecum. The relative abundance and the inferred absolute abundance of Faecalibacterium prausnitzii at PND49 were significantly higher than that at PND14 in Yorkshire piglets. Pig breeds did not affect the dsrA gene copies of SRB, diversity index and community pattern of SRB. Conclusions:Sulfate-reducing bacteria are widely colonized in the cecum of piglets and D. intestinalis is the dominant SRB. The age of piglets, but not the pig breeds affects the diversity and community pattern of SRB.
Project description:Nursing mother and breed can differently regulate early-life microbiota succession in pigs. However, it remains unclear whether they affect gastrointestinal microbiota and immune status, which are critical for early-life gut health. Here, an interspecific cross-fostering piglet model was employed by fostering neonatal Yorkshire and Meishan piglets to the same or another breed of sows. Jejunal and colonic microbiotas and mucosal immune parameters were analyzed at postnatal days 14 (preweaning) and 49 (postweaning). Nursing mother affected 10 genera in the colon and 3 minor genera in the jejunum. At day 14, Meishan sow-nursed piglets had lower Streptococcus suis and higher Cloacibacillus counts in the colonic digesta and larger amounts of interleukin 10 and Foxp3-positive cells in the colonic mucosa than did Yorkshire sow-nursed piglets. At day 49, nursing mother had no significant effects on cytokine expression. Breed effects were observed; Meishan piglets had lower relative abundances of Prevotella and lower gene expression of tumor necrosis factor alpha (TNF-?) than those of Yorkshire piglets at days 14 and 49. Collectively, nursing mother mainly affected preweaning colonic microbiota and immune status, while breed effects persisted after weaning. Piglets nursed by Meishan sows had different microbiota compositions and inflammatory cytokine profiles in the colon compared with those of piglets nursed by Yorkshire sows. These results highlight the different role of nursing mother and breed in affecting early gut microenvironment.IMPORTANCE Early-life gut microbiota and immune status are pivotal for postnatal growth. By using an interspecific cross-fostering piglet model, we find that change in nursing mother transiently reshapes preweaning colon microbiota and immune status, while breed shows persistent effects both pre- and postweaning. Piglets nursed by Meishan sows had lower Streptococcus suis counts and higher anti-inflammatory cytokine expression. These results highlight the significance of nursing mother in regulating early-life gut health.
Project description:The expression patterns in Meishan- and Yorkshire-derived endometrium during early (gestational day 15) and mid-gestation (gestational days 26 and 50) were investigated, respectively. Totally, 689 and 1649 annotated genes were identified to be differentially expressed in Meishan and Yorkshire endometrium during the three gestational stages, respectively. Hierarchical clustering analysis identified that, of the annotated differentially expressed genes (DEGs), 73 DEGs were unique to Meishan endometrium, 536 DEGs were unique to Yorkshire endometrium, and 228 DEGs were common in Meishan and Yorkshire endometriums. Subsequently, DEGs in each of the three types of expression patterns were grouped into four distinct categories according to the similarities in their temporal expression patterns. The expression patterns identified from the microarray analysis were validated by quantitative RT-PCR. The functional enrichment analysis revealed that the common DEGs were enriched in pathways of steroid metabolic process and regulation of retinoic acid receptor signaling. These unique DEGs in Meishan endometrium were involved in cell cycle and adherens junction. The DEGs unique to Yorkshire endometrium were associated with regulation of Rho protein signal transduction, maternal placenta development and cell proliferation. This study revealed the different gene expression patterns or pathways related to the endometrium remodeling in Meishan and Yorkshire pigs, respectively. These unique DEGs in either Meishan or Yorkshire endometriums may contribute to the divergence of the endometrium environment in the two pig breeds.
Project description:Time-dependent expression of functional proteins in fetal ovaries is important to understand the developmental process of the ovary. This study was carried out to enhance our understanding of the developmental process of porcine fetal ovaries and to better address the differences in fetal ovary development of local and foreign pigs. The objective of the present study is to test the expression of key proteins that regulate the growth and development of fetal ovaries in Meishan and Yorkshire porcine breeds by using proteomics technology. Six Meishan and 6 Yorkshire pregnant gilts were used in this experiment. Fetal ovaries were obtained from Yorkshire and Meishan gilts on days 55 and 90 of the gestation period. Using 2D-DIGE (two dimensional-difference in gel electrophoresis) analysis, the results showed that there are about 1551 and 1400 proteins in gilt fetal ovaries on days 55 and 90, respectively of the gestation. Using MALDI TOF-TOF MS analysis, 27 differentially expressed proteins were identified in the fetal ovaries of the 2 breeds on day 55 of gestation, and a total of 18 proteins were identified on day 90 of gestation. These differentially expressed proteins were involved in the regulation of biological processes (cell death, stress response, cytoskeletal proteins) and molecular functions (enzyme regulator activity). We also found that alpha-1-antitrypsin, actin, vimentin, and PP2A proteins promote the formation of primordial follicles in the ovaries of Yorkshire pigs on day 55 of gestation while low expression heat shock proteins and high expression alpha-fetoproteins (AFP) may promote Meishan fetal ovarian follicular development on day 90 of gestation. These findings provide a deeper understanding of how reduced expression of heat shock proteins and increased expression of AFP can significantly reduce the risk of reproductive disease in obese Meishan sows. Our study also shows how these proteins can increase the ovulation rate and may be responsible for the low reproductive efficiency reported in other obese breeds. The ovarian developmental potential was found to be greater in Meishan pigs than in Yorkshire pigs.
Project description:This study investigated the effect of feed supplementation in sows and/or their progeny with 2 sensory feed additives (FA1: limonene and cinnamaldehyde; FA2: menthol, carvone, and anethole) on sows' feed intake, body weight, fat deposition, and colostrum/milk composition, as well as piglets' feed intake growth and feed efficiency from birth to slaughter at postnatal day 160 (PND160). During the last third of gestation and the whole of lactation, sows were subjected to a control diet (C) or the same diet containing FA1 or FA2 at 0.1% of complete feed content. Colostrum/milk samples were taken at days 1, 14, and 28 of lactation for gas chromatography-mass spectrometry analyses. After weaning, the progeny was subjected to a control diet (C) or experimental diets with a sweetener (0.015%) but no other additive (S), or to diets with a sweetener and the additive FA1 (FA1S) or FA2 (FA2S). There was no effect of dietary treatment on sows' feed intake, body weight, or adiposity (P > 0.15 for all), but the sensory characteristics of their colostrum/milk were modified by the diet and diet*time interaction. Limonene concentrations were higher in FA1 samples from PND1 to PND28, whereas carvone and anethole concentrations were higher in FA2 samples from PND1 to PND28. The concentration of these 3 compounds increased with time in the respective groups where they were mostly detected. Menthol concentrations were higher in FA2 samples at PND14 and PND28, but there was no time effect. Overall, cinnamaldehyde was always below the detection range. Piglets born from FA1 and FA2 sows had higher body weight (P = 0.034 at PND160), average daily gain (ADG; P = 0.036 for PND0-160), and average daily feed intake (ADFI; P = 0.006 for PND28-160) than piglets born from C sows. Overall, piglets that were never exposed to FA or only after weaning had lower ADG (P = 0.030 for PND0-160) and ADFI (P = 0.016 for PND28-160) than piglets that were exposed to FA only via the maternal diet, the condition combining both pre- and post-natal exposure being intermediary. In conclusion, FA1 and FA2 provided to gestating and lactating sows increased the progeny's feed intake and growth, suggesting nutritional programming and/or sensory conditioning during the perinatal period. Addition of FA only in the progeny's diet was not beneficial.
Project description:BACKGROUND: Litter size in pigs is a major factor affecting the profitability in the pig industry. The peri-implantation window in pigs is characterized by the coordinated interactions between the maternal uterine endometrium and the rapidly elongating conceptuses and represents a period of time during which a large percentage of the developing conceptuses are lost. However, the gene expression and regulatory networks in the endometrium contributing to the establishment of the maternal: placental interface remain poorly understood. RESULTS: We characterized the endometrial gene expression profile during the peri-implantation stage of development by comparing two breeds that demonstrate very different reproductive efficiencies. We employed the porcine Affymetrix GeneChip® to assay the transcriptomic profiles of genes expressed in the uterine endometrium obtained from Meishan and Yorkshire gilts (n = 4 for each breed) on day 12 of gestation (M12 and Y12, respectively). Total of 17,076 probesets were identified as "present" in at least two arrays. A mixed model-based statistical analysis predicted a total of 2,656 (q < 0.1) transcripts as differentially expressed between Meishan and Yorkshire pigs. Eighteen differentially expressed transcripts of interest were validated by quantitative real-time PCR. Gene ontology (GO) annotation revealed that the known functions of the differentially expressed genes were involved in a series of important biological processes relevant to early pregnancy establishment in the pig. CONCLUSIONS: The results identified endometrial gene expression profiles of two breeds differing in litter size and identified candidate genes that are related to known physiological pathways related to reproductive prolificacy. These findings provide a deeper understanding of molecular pathways differing between two breeds at the critical peri-implantation stage of pregnancy, which can be utilized to better understand the events contributing to pregnancy establishment in the pig. Meishan and Yorkshire breeds endometirum were selected and RNA been extracted and hybridized to the Affymetrix microarray. A number of genes have been shown differently expressed on two breeds.
Project description:BACKGROUND:The Korean native pig (KNP) is generally thought to have come from northern China to the Korean peninsula approximately 2000 years ago. KNP pigs were at the brink of extinction in the 1980s, since then efforts have been made to restore the breed by bringing together the remaining stocks in South Korea. As a result, KNP was registered as a breed in 2006. To find additional breed-specific markers that are distinct among pig breeds, variations in O-linked N-acetylglucosamine transferase (OGT) were investigated. OGT is located on chromosome X and catalyzes the post-translational addition of a single O-linked-?-N-acetylglucosamine to target proteins. FINDINGS:Length polymorphism in the intron 20 of OGT was identified. The intron 20 of OGT from Duroc, Landrace, and Yorkshire breeds was 281-bp longer than that from either KNP or Chinese Meishan pigs. The difference between the Western pig breeds (BB genotype) and KNP or Meishan pigs (AA genotype) was due to an inserted 276-bp element and the 5-bp ACTTG. CONCLUSIONS:The polymorphism in OGT identified in this study may be used as an additional marker for determining the breed of origin among Meishan and the Western pig breeds. The length polymorphism suggests that the locus near OGT is not fixed in KNP. This marker would be relevant in determining the breed of origin in crossbred pigs between KNP pigs with known genotypes and the Western pig breeds with BB genotypes, thus confirming the contribution of the X chromosome from each breed.
Project description:Background:Reproductive performance of livestock is an economically important aspect of global food production. The Chinese Meishan pig is a prolific breed, with an average of three to five more piglets per litter than European breeds; however, the genetic basis for this difference is not well understood. Results:In this study, we investigated copy number variations (CNVs) of 32 Meishan pigs and 29 Duroc pigs by next-generation sequencing. A genome-wide analysis of 61 pigs revealed 12,668 copy number variable regions (CNVRs) that were further divided into three categories based on copy number (CN) of the whole population, i.e., gain (n?=?7,638), and loss (n?=?5,030) CNVRs. We then compared Meishan and Duroc pigs and identified 17.17?Mb of 6,387 CNVRs that only existing in Meishan pigs CNVRs that overlapped the reproduction-related gene encoding the aryl hydrocarbon receptor (AHR) gene. We found that normal AHR CN was more frequent than CN loss in four different pig breeds. An association analysis showed that AHR CN had a positive effect on litter size (P?<?0.05) and that a higher CN was associated with higher total number born (P?<?0.05), number born alive (P?<?0.05), number of weaned piglets, and birth weight. Conclusions:The present study provides comprehensive CNVRs for Meishan and Duroc pigs through large-scale population resequencing. Our results provide a supplement for the high-resolution map of copy number variation in the porcine genome and valuable information for the investigation of genomic structural variation underlying traits of interest in pig. In addition, the association results provide evidence for AHR as a candidate gene associated with reproductive traits that can be used as a genetic marker in pig breeding programs.
Project description:Children exposed to abuse or neglect show abnormal hippocampal development and similar findings have been reported in rodent models. Using brief daily separation (BDS), a mouse model of early life stress, we previously showed that exposure to BDS impairs hippocampal function in adulthood and perturbs synaptic maturation, synaptic pruning, axonal growth and myelination in the developing hippocampus. Given that microglia are involved in these developmental processes, we tested whether BDS impairs microglial activity in the hippocampus of 14 (during BDS) and 28-day old mice (one week after BDS). We found that BDS increased the density and altered the morphology of microglia in the hippocampus of 14-day old pups, effects that were no longer present on postnatal day (PND) 28. Despite the normal cell number and morphology seen at PND28, the molecular signature of hippocampal microglia, assessed using the NanoString immune panel, was altered at both ages. We showed that during normal hippocampal development, microglia undergo significant changes between PND14 and PND28, including reduced cell density, decreased ex vivo phagocytic activity, and an increase in the expression of genes involved in inflammation and cell migration. However, microglia harvested from the hippocampus of 28-day old BDS mice showed an increase in phagocytic activity and reduced expression of genes that normally increase across development. Promoter analysis indicated that alteration in the transcriptional activity of PU.1, Creb1, Sp1, and RelA accounted for most of the transcriptional changes seen during normal microglia development and for most of the BDS-induced changes at PND14 and PND28. These findings are the first to demonstrate that early life stress dysregulates microglial function in the developing hippocampus and to identify key transcription factors that are likely to mediate these changes.
Project description:Since CNVs play a vital role in genomic studies, it is an imperative need to develop a comprehensive, more accurate and higher resolution porcine CNV map with practical significance in follow-up CNV functional analyses To detect CNV of pigs, we performed high density aCGH data of diverse pig breeds in the framework of the pig draft genome sequence (Sscrofa10.2) 9 Chinese indigenous pig, one Chinese wild boar and 2 commercial pigs were detected using one pig of Duroc as reference. These 12 animals include 1 wild pig, 2 pigs each from Yorkshire and Landrace as the representatives of modern commercial breeds and 9 unrelated individuals selected from 6 Chinese indigenous breeds (2- Tibetan pig, 2- Diannan small-ear pig, 2-Meishan pig, 1- Min pig, 1-Daweizi pig, and 1-Rongchang pig).
Project description:BACKGROUND: Litter size in pigs is a major factor affecting the profitability in the pig industry. The peri-implantation window in pigs is characterized by the coordinated interactions between the maternal uterine endometrium and the rapidly elongating conceptuses and represents a period of time during which a large percentage of the developing conceptuses are lost. However, the gene expression and regulatory networks in the endometrium contributing to the establishment of the maternal: placental interface remain poorly understood. RESULTS: We characterized the endometrial gene expression profile during the peri-implantation stage of development by comparing two breeds that demonstrate very different reproductive efficiencies. We employed the porcine Affymetrix GeneChip® to assay the transcriptomic profiles of genes expressed in the uterine endometrium obtained from Meishan and Yorkshire gilts (n = 4 for each breed) on day 12 of gestation (M12 and Y12, respectively). Total of 17,076 probesets were identified as "present" in at least two arrays. A mixed model-based statistical analysis predicted a total of 2,656 (q < 0.1) transcripts as differentially expressed between Meishan and Yorkshire pigs. Eighteen differentially expressed transcripts of interest were validated by quantitative real-time PCR. Gene ontology (GO) annotation revealed that the known functions of the differentially expressed genes were involved in a series of important biological processes relevant to early pregnancy establishment in the pig. CONCLUSIONS: The results identified endometrial gene expression profiles of two breeds differing in litter size and identified candidate genes that are related to known physiological pathways related to reproductive prolificacy. These findings provide a deeper understanding of molecular pathways differing between two breeds at the critical peri-implantation stage of pregnancy, which can be utilized to better understand the events contributing to pregnancy establishment in the pig.