Meishan Sows Research Articles

Omentin expression in the ovarian follicles of Large White and Meishan sows during the oestrous cycle and in vitro effect of gonadotropins and steroids on its level: Role of ERK1/2 and PI3K signaling pathways.

Omentin (ITLN1) is a novel adipokine mainly expressed in the white adipose tissue. It plays a crucial role in the metabolic homeostasis and insulin sensitivity. Our last study documented that ITLN1 levels in the adipose tissue and plasma are lower in fat Meishan (MS) compared to normal weight Large White (LW) pigs. The aim of this study was to investigate transcript and protein concentrations of ITLN1 as well as its immunolocalisation in the ovarian follicles and examine the molecular mechanism involved in the regulation of its expression in response to gonadotropins (FSH, LH) and steroids (P4, T, E2). Ovarian follicles were collected from LW and MS sows on days 2-3, 10-12, and 14-16 of the oestrous. We found the elevated ITLN1 expression in the ovarian follicles and the increase of concentrations in follicular fluid (FF) of LW pigs vs MS pigs; in both breeds of pigs, the levels of ITLN1 increased with the oestrous progression. We noted ITLN1 signals in oocyte, granulosa and theca cells. Gonadotropins and steroids increased ITLN1 levels in the ovarian follicle cells of LW pigs, while in MS pigs, we observed only the stimulatory effect of LH and T. Both extracellular signal-regulated kinase (ERK1/2) and phosphatidylinositol 3'-kinase (PI3K) were involved in the regulation of ITLN1. Our study demonstrated the levels and regulation of ITLN1 in the porcine ovarian follicles through ERK1/2 and PI3K signaling pathways.

Multi-omics analysis reveals the dominant intestinal microbial strains and metabolites related to the reproductive performance in pregnant sows

Abstract Gut microbiome changed dramatically during pregnancy and played important roles in metabolic status and reproductive endocrinology in mammals. However, investigating the functional microbiota and metabolites to improve the reproductive performance and understanding the host–microbiota interaction are still arduous tasks. This study aims to reveal the dominant strains and metabolites that improve the reproductive performance. We analyzed the fecal microbiota composition and metabolic status of higher yield Chinese pig breed Meishan (MS) sows and lower yield but widespread raised hybrid pig breed Landrace × Yorkshire (L × Y) sows on days 28 and 100 of gestation. Results showed that MS sows had higher litter sizes and steroid hormone level but lower short-chain fatty acid level in feces. Fecal metabolomic analysis revealed that MS sows showed a different metabolic status compared with L × Y sows both at early and late pregnancy, which enriched with phenylpropanoid biosynthesis, bile secretion, steroid hormone biosynthesis, and plant secondary metabolite biosynthesis. In addition, 16S rDNA and internal transcribed spacer sequencing indicated that MS sows showed different structures of microbiota community and exhibited an increased bacterial α-diversity but non-differential fungal α-diversity than L × Y sows. Moreover, we found that the litter sizes and bacteria including Sphaerochaeta, Solibacillus, Oscillospira, Escherichia–Shigella, Prevotellaceae_UCG-001, dgA-11_gut_group, and Bacteroides, as well as fungi including Penicillium, Fusarium, Microascus, Elutherascus, and Heydenia both have positive association to the significant metabolites at the early pregnancy. Our findings revealed significant correlation between reproductive performance and gut microbiome and provided microbial and metabolic perspective to improve litter sizes and steroid hormones of sows.

38. Comparison of placenta metabolism at the end of gestation between Large White and Meishan sows

38. Comparison of placenta metabolism at the end of gestation between Large White and Meishan sows

Transcriptome analysis of miRNAs and mRNAs of medium-sized ovarian follicles of Duroc and Meishan sows

Litter size is an economically important trait in the swine industry. A high ovulation rate is a prerequisite for a large litter size. It differs among pig breeds with different genetic backgrounds. During the middle-late follicular stage, the medium-sized follicles (3–6.9 mm) of sows with a high ovulation rate can maintain their potential for development into ovulatory follicles. In this study, Meishan and Duroc sows were utilized as model animals due to their extreme litter size phenotypes. M2 follicles (5–6.9 mm) were collected on Day 4 of the follicular phase for high-throughput sequencing of small RNAs and mRNAs. Differentially expressed miRNAs (DEMs) and differentially expressed genes (DEGs) were analyzed. KEGG pathway and GO enrichment analyses were conducted to analyze the DEGs and the target genes of DEMs, resulting in the construction of a regulatory network of DEMs-DEGs. A total of 402 miRNAs were identified, with 8 upregulated and 3 downregulated miRNAs in the Meishan group. KEGG pathway analysis revealed significant enrichment of target genes of DEMs in pathway such as Apoptosis, GnRH signaling pathway, MAPK signaling pathway, and PI3K-Akt signaling pathway. GO enrichment analysis revealed 1930 significantly enriched GO terms. KEGG pathway analysis of the DEGs revealed 13 significantly enriched pathways, including those involved in complement and coagulation cascades, ECM-receptor interactions, and PI3K-Akt signaling pathway. A total of 642 GO terms were significantly enriched. Through Pearson correlation analysis, 67 DEM-DEG pairs were identified, and 62 DEGs were found to be regulated by 9 DEMs. This study provides valuable insights into the function of miRNAs and mRNAs in regulating the growth and development of follicles.

Multi-omics analysis reveals gut microbiota-ovary axis contributed to the follicular development difference between Meishan and Landrace × Yorkshire sows

BackgroundThe mechanism by which Meishan (MS) sows are superior to white crossbred sows in ovarian follicle development remains unclear. Given gut microbiota could regulate female ovarian function and reproductive capacity, this study aimed to determine the role of gut microbiota-ovary axis on follicular development in sows.MethodsWe compared the ovarian follicular development, gut microbiota, plasma metabolome, and follicular fluid metabolome between MS and Landrace × Yorkshire (L × Y) sows. A H2O2-induced cell apoptosis model was used to evaluate the effects of multi-omics identified metabolites on the apoptosis of porcine ovarian granulosa cells in vitro.ResultsCompared with L × Y sows, MS sows have greater ovary weight and improved follicular development, including the greater counts of large follicles of diameter ≥ 5 mm, secondary follicles, and antral follicles, but lesser atretic follicles. The ovarian granulosa cells in MS sows had alleviated apoptosis, which was indicated by the increased BCL-2, decreased caspases-3, and decreased cleaved caspases-3 than in L × Y sows. The ovarian follicular fluid of MS sows had higher concentrations of estradiol, progesterone, follicle-stimulating hormone, luteinizing hormone, and insulin like growth factor 1 than L × Y sows. Gut microbiota of MS sows formed a distinct cluster and had improved alpha diversity, including increased Shannon and decreased Simpson than those of L × Y sows. Corresponding to the enhanced function of carbohydrate metabolism and elevated short-chain fatty acids (SCFAs) in feces, the differential metabolites in plasma between MS and L × Y sows are also mainly enriched in pathways of fatty acid metabolism. There were significant correlations among SCFAs with follicular development, ovarian granulosa cells apoptosis, and follicular fluid hormones, respectively. Noteworthily, compared with L × Y sows, MS sows had higher follicular fluid SCFAs concentrations which could ameliorate H2O2-induced porcine granulosa cells apoptosis in vitro.ConclusionMS sows have more secondary and antral follicles, but fewer atretic follicles and apoptotic ovarian granulosa cells, as well as harbored a distinctive gut microbiota than L × Y sows. Gut microbiota may participate in regulating ovarian follicular development via SCFAs affecting granulosa cells apoptosis in sows.

Identification of circular RNAs in the ovarian follicles of Meishan and Duroc sows during the follicular phase

Circular RNAs (circRNAs) are a newly discovered class of endogenous non-coding RNAs that play an important role in growth and development by regulating gene expression and participating in a variety of biological processes. However, the role of circRNAs in porcine follicles remains unclear. Therefore, this study examined middle-sized ovarian follicles obtained from Meishan and Duroc sows at day 4 of the follicular phase. High-throughput RNA sequencing (RNA-seq) was utilized to construct circRNAs, and differential expression was identified. The findings were validated using reverse transcription PCR (RT-PCR) and DNA sequencing, GO and KEGG analyses were performed, and potential miRNA targets were identified. The RNA-seq identified a total of 15,866 circRNAs, with 244 differentially expressed in the Meishan relative to the Duroc (111 up-regulated and 133 down-regulated). The RT-PCR finding confirmed the RNA-seq results, and quantitative real-time PCR (qPCR) analysis examining a subset of the circRNAs showed that they are resistant to RNase R digestion. Bioinformatics analysis (GO and KEGG) showed that the host genes associated with the differentially expressed circRNAs are involved in reproduction and follicular development signaling pathways. Furthermore, many of the circRNAs were found to interact with miRNAs that are associated with follicular development. This study presents a new perspective for studying circRNAs and provides a valuable resource for further examination into the potential roles of circRNAs in porcine follicular development.

Adipokines expression profiles in both plasma and peri renal adipose tissue in Large White and Meishan sows: A possible involvement in the fattening and the onset of puberty

In pig, backfat deposition is strongly related to the growth and reproductive performance. However, the molecular regulatory mechanisms of adipose tissue are not clearly understood. Adipose tissue is now recognized as an important endocrine organ that secretes a variety of factors including adipokines. However, the regulation of expression pattern of these adipokines in both plasma and visceral white adipose tissue (WAT) in lean and fat pig is unclear. In the present study, we used two representative porcine breeds (Large White, LW; Meishan, MS) with contrasting backfat thickness and sexual maturity age. Using specific ELISA assays, we determined the plasma profile of eight adipokines, leptin, adiponectin, visfatin, apelin, chemerin, resistin, omentin and vaspin in LW and MS sows. By RT-qPCR and western-blot we also investigated the mRNA and protein levels of these adipokines and their cognate receptors (LEPR, ADIPOR1, ADIPOR2, CMKLR1, CCRL2, GPR1, APLNR, TLR4, ROR1, CAP1 and HSPA5) in the peri renal WAT, respectively. At both plasma and peri renal WAT level, we found that the amounts of leptin, chemerin, resistin and vaspin were higher whereas those of adiponectin and omentin were lower in MS than LW sows. Plasma and adipose tissue visfatin and apelin levels were not different between the two breeds. Moreover, we noted that the variations of peri renal WAT adipokines observed between MS and LW were similar at the protein and mRNA level except for chemerin and apelin suggesting post-transcriptional modifications for these two adipokines. Finally, among the eight adipokines studied, we showed that only the plasma concentrations of leptin and chemerin were positively and those of adiponectin, negatively associated with the thickness of fat and opposite correlation was found for the onset of puberty in both LW and MS animals. Taken together, these results support a potential involvement of adipokines in WAT regulation and its link with the onset of the puberty in sows.

Frameshift mutation in myostatin gene by zinc-finger nucleases results in a significant increase in muscle mass in Meishan sows

Myostatin (MSTN) is a negative regulator of skeletal muscle growth and development. A significant increase in skeletal muscle was observed in Mstn<sup>−/−</sup> mice compared with wild-type mice. So far, there has been no report on porcine MSTN mutations leading to skeletal muscle hypertrophy. In this report a MSTN frameshift mutation missing 11 nucleotides in exon 2 was introduced into Meishan pigs by zinc finger nuclease (ZFN) technology. ZFN-edited MSTN<sup>−/−</sup> Meishan pigs were successfully produced by a cloning method of somatic cell nucleus transfer. Results from slaughter experiments indicated that lean meat yield increased 16.53% in about 80 kg (10-months-old) MSTN<sup>−/−</sup> Meishan sows compared with their corresponding wild-type counterparts. The lean percentage of carcass from MSTN<sup>−/−</sup> sows was 61.20% vs 48.25% for MSTN<sup>+/−</sup> sows and 44.67% for wild-type sows. The fat of MSTN<sup>−/−</sup> sows was significantly lower than that of MSTN<sup>+/−</sup> and wild-type sows. The loin eye area of MSTN<sup>−/−</sup> Meishan sows (56.42 cm<sup>2</sup>) was greater than that of MSTN<sup>+/−</sup> (37.39 cm<sup>2</sup>) and wild-type (26.26 cm<sup>2</sup>) sows. The muscle fibre area of longissimus muscle in wild-type Meishan sows (1 946 μm<sup>2</sup>) was significantly greater than that of MSTN<sup>+/−</sup> (1 324 μm<sup>2</sup>) and MSTN<sup>−</sup><sup>/−</sup> (1 419 μm<sup>2</sup>) sows. Moreover the significantly increased skeletal muscle in these MSTN<sup>−/−</sup> Meishan sows was mainly due to the increase in the number of myofibres rather than to hypertrophy. Compared with wild-type Meishan sows, it was noted that myofibres had transformed from type I to IIB in MSTN<sup>−/−</sup> Meishan sows. Our present study demonstrated that frameshift mutation in MSTN by ZFN technology led to a significant increase in muscle mass and a significant decrease in fat content in Meishan sows.

Effect of MSTN Mutation on Growth and Carcass Performance in Duroc x Meishan Hybrid Population.

Simple SummaryMyostatin (MSTN) is a transcriptional growth factor that inhibits the development and growth of skeletal muscle. The MSTN-deficient animals display an increase in skeletal muscle mass known as double-muscling. Therefore, MSTN becomes an important target for improving lean meat production in livestock husbandry. There are many local pig breeds in China, but because of the slow growth, poor feed conversion, and low lean meat percentage and other unsatisfactory qualities, pure local breeds are rarely used on commercial farms. The objective of this study is to evaluate the effects of MSTN single allele mutation on carcass composition in Meishan crossbred pigs and demonstrate a way to increase lean meat yield while maintaining prolificacy and good meat quality of local pig crossbreeds. This has significant implications for the widespread use and conservation of local pig breeds in China.The Meishan pig is a traditional Chinese native breed, known for its excellent reproduction performance that is widely used in commercial pig production through two-way or three-way crossbreeding systems. However, the lean meat yield of Meishan crossbred pigs is still very low and cannot meet the market demand. To evaluate the lean meat yield of Meishan crossbred pigs, six wild-type Meishan sows were artificially inseminated by using the MSTN+/− Duroc boar semen in this experiment. Some reproductive performance-related traits of Meishan sows were recorded to ensure that semen from MSTN knockout Duroc boar did not affect offspring production, including total births, live births, sex, and litter weight. In total, 73 piglets were obtained and 63 were alive. Male to female ratio was close to 1: 1. because of factors such as disease, only 43 pigs were utilized, including 28 MSTN mutant pigs (MSTN+/−) and 15 MSTN homozygous pigs (MSTN+/+). We compared the growth performance and carcass performance of these full or half-sib populations and found that there were no differences between MSTN+/− and MSTN+/+ genotypes for live animal measures including average daily gain (ADG), body dimensions, or ultrasonic measurement of fat thickness when pigs were harvested after 120 days of feeding. Conversely, the MSTN+/− pigs had higher dressing percentage and lean meat percentage, lower level of carcass fat, larger longissimus muscle area, less percentage of skin and skeleton, thinner average backfat thickness, and lower intramuscular fat (IMF) content than MSTN+/+ pigs. In conclusion, the production of MSTN+/− mutant progeny from Meishan females resulted in improved carcass composition, providing a feasible solution to improve the lean meat yield of Chinese local fat-type pig breeds.

Protein expression profiles in Meishan and Duroc sows during mid-gestation reveal differences affecting uterine capacity, endometrial receptivity, and the maternal\u2013fetal Interface

BackgroundEmbryonic mortality is a major concern in the commercial swine industry and primarily occurs early in gestation, but also during mid-gestation (~ days 50–70). Previous reports demonstrated that the embryonic loss rate was significant lower in Meishan than in commercial breeds (including Duroc). Most studies have focused on embryonic mortality in early gestation, but little is known about embryonic loss during mid-gestation.ResultsIn this study, protein expression patterns in endometrial tissue from Meishan and Duroc sows were examined during mid-gestation. A total of 2170 proteins were identified in both breeds. After statistical analysis, 70 and 114 differentially expressed proteins (DEPs) were identified in Meishan and Duroc sows, respectively. Between Meishan and Duroc sows, 114 DEPs were detected at day 49, and 98 DEPs were detected at day 72. Functional enrichment analysis revealed differences in protein expression patterns in the two breeds. Around half of DEPs were more highly expressed in Duroc at day 49 (DUD49), relative to DUD72 and Meishan at day 49 (MSD49). Many DEPs appear to be involved in metabolic process such as arginine metabolism. Our results suggest that the differences in expression affect uterine capacity, endometrial matrix remodeling, and maternal-embryo cross-talk, and may be major factors influencing the differences in embryonic loss between Meishan and Duroc sows during mid-gestation.ConclusionsOur data showed differential protein expression pattern in endometrium between Meishan and Duroc sows and provides insight into the development process of endometrium. These findings could help us further uncover the molecular mechanism involved in prolificacy.

Maternal high-protein diet modulates hepatic growth axis in weaning piglets by reprogramming the IGFBP-3 gene

PurposeThe aim of this study was to investigate the effects of maternal high dietary protein intake on the hepatic growth axis in offspring.MethodsFourteen primiparous purebred Meishan sows were fed either a standard-protein (SP, n = 7) diet or a high-protein (HP, 150% of SP, n = 7) diet during pregnancy. Offspring (one male and one female per group, n = 14) on day 70 of the embryonic stage and on days 1, 35 and 180 after birth were selected, weighed and killed. Serum samples were analyzed for Tch, insulin and insulin-like growth factor-binding protein 3 (IGFBP-3) levels. Liver samples were analyzed for IGFBP-3 and IGF-I mRNA expression by qRT-PCR and for IGFBP-3, IGF1R and growth hormone receptor (GHR) protein expression by Western blotting. The underlying mechanism of IGFBP-3 regulation was determined by methylated DNA immunoprecipitation (MeDIP) and chromatin immunoprecipitation (ChIP).ResultsHigh-protein exposure resulted in significantly higher body and liver weights of piglets, and it increased their serum T3 and T4 levels at birth and/or at weaning. Furthermore, the IGFBP-3 protein content in the liver and serum was significantly reduced in the HP-exposed weaning piglets, whereas at the transcriptional level IGFBP-3 mRNA expression was downregulated in the livers of HP group piglets. Finally, DNA hypermethylation and higher enrichment of the histone repressive marks H3K27me3 and H3K9me3 were observed.ConclusionsTaken together, these results suggest that a maternal high-protein diet during gestation epigenetically reprograms IGFBP-3 gene expression to modulate the hepatic growth axis in weaning piglets.

Differential Effects of Breed and Nursing on Early-Life Colonic Microbiota and Immune Status as Revealed in a Cross-Fostering Piglet Model.

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-α) 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.

Crude fiber modulates the fecal microbiome and steroid hormones in pregnant Meishan sows

The beneficial effects of dietary fiber on the reproductive performance and welfare of sows have been discussed broadly, but few researches examined the causal changes and the association of gut microbiota and the steroid hormones, the main regulators of reproductive function. To shed light on this, thirty-six Meishan sows were allocated into 2.5% crude fiber (CF) group and 7.5% CF group respectively for an entire farrowing interval. On the 90th day of gestation, the saliva and fresh stool of sows were individually collected in the morning (06:00–07:00) for steroid hormones, short-chain fatty acids (SCFAs) and microbiome analysis. In addition, the parameter of pregnant behavioral and farrowing performance was recorded and evaluated. We observed that, as compared with the 2.5% CF treatment, 7.5% CF significantly increased the litter size (p = 0.01), reduced the stereotypic behaviors including sham chewing, rolling tongue and licking ground (p = 0.02, 0.04, 0.01) at later gestation stage, but increased lying time (p = 0.00). In coincide with this, 7.5% CF diet increased the salivary progesterone (p = 0.00), fecal estradiol and progesterone (p = 0.01, 0.02) level, fecal water and SCFAs content (p = 0.02, 0.03), decreased the salivary and fecal cortisol (p = 0.01, 0.00) level. Further, 7.5% CF diet increased the fecal microbiota richness (ACE, p = 0.04; Chao, p = 0.07) and diversity (Shannon, p = 0.01; Simpson, p = 0.04), the proportion of genus Ruminococcus, Butyrivibrio, Lactobacillus and Fibrobacter (p = 0.02, 0.05, 0.04, 0.00), whereas reduced the proportion of genus Clostridium, Streptococcus, Bacteroides and Escherichia-Shigella (p = 0.00, 0.00, 0.04, 0.04). These results indicate that, fibrous diet can regulate the steroid hormones secretion and modulate the gut with more cellulose-degrading and probiotic bacterium, but less opportunistic pathogens, and this may contribute to the improvement of reproductive performance and welfare in sows.

Identification of differentially expressed microRNAs in middle-size ovarian follicles of Meishan and Duroc sows

ABSTRACT This study aimed to investigate the roles of miRNA in the development of ovarian follicles in sows with high ovulation rate. The miRNA expression profiles in middle-size ovarian follicles between Meishan and Duroc sows were characterized by Affymetrix miRNA GeneChip. Seven differentially expressed miRNA were identified. KEGG pathways analyzed the predicted target genes of differentially expressed miRNA by using the DAVID website. The MAPK signaling pathway may affect the process of ovarian follicle development. Our study suggested that miR-21, [...]

New Insights into Porcine Milk N-Glycome and the Potential Relation with Offspring Gut Microbiome.

N-Glycans are an important source of milk oligosaccharides. In addition to free oligosaccharides found in milk, N-glycans can also be utilized by gut microbes. A potential for milk N-glycans to act as gut microbe regulators in suckling animals has attracted considerable attention; however, sow milk N-glycans and their potential effects upon the piglet's gut microbes in vivo remain unknown. In the present study, we profiled the milk N-glycans of Meishan and Yorkshire sows during lactation using UPLC and a mass spectrometry-based glycome method, and we explored the correlations between milk N-glycans and offspring gut microbiota. Twenty-two N-glycan structures were identified in sow milk, among which 36% (8 out of 22) were fucosylated, 41% (9 out of 22) were sialylated, and 14% (3 out of 22) were high mannosylated. An N-glycan with a NeuGc structure (namely PNO20, GlcNAc4-Man3-Gal2-Fuc-Neu5Gc) was identified in sow milk for the first time. No compositional differences between the two breeds or between different lactation times were found in porcine milk N-linked oligosaccharides (PNOs); however, the abundances of different structures within this class did vary. The relative abundances of fucosylated PNO3 (GlcNAc4-Man3-Fuc) and sialylated PNO18 (GlcNAc4-Man3-Gal2-NeuAc) increased during lactation, and Meishan sows demonstrated a higher ( P < 0.05) abundance of mannosylated PNO10 (GlcNAc2-Man6) and sialylated PNO17 (GlcNAc5-Man3-Gal-NeuAc) than Yorkshire sows. Apparent correlations between milk N-glycans and offspring gut microbial populations were found; for example, mannosylated PNO21 (GlcNAc2-Man9) was positively correlated with OTU706 ( Lactobacillus amylovorus) and OTU1380 ( Bacteroides uniformis). Overall, our results indicate that the milk N-glycome of Meishan and Yorkshire sows differs in N-glycome characteristics and that this is correlated to abundances of certain piglet gut microbes. These findings provide a reference for future elucidation of the involvement of gut microbes in milk N-glycan metabolism, which is important to the health both of large domestic animals and humans.

Asphyxia occurrence detection in sows during the farrowing phase by inter-birth interval evaluation

The occurrence of asphyxia in sows during parturition often results in stillbirths and low vitality piglets, thus significantly affecting pig production and animal welfare in terms of piglet mortality. The losses during farrowing can account to a significant loss in a litter, a whole litter or in extreme cases, the loss of the sow. The objective of this study was to develop an infrared depth image sensor-based monitoring system as a surveillance support system for stockmen during the farrowing phase of sows, in an effort to reduce piglet mortality associated with asphyxiation of piglets. Experiments were performed at Jurong Research farm of Nanjing Agricultural University, using a herd of 105 Meishan sows. Data was collected by monitoring the farrowing process of 15 sows housed in farrowing pens. The sows were monitored by video recording for labeling and depth images taken at 10 fpm for automatic system development. Data labeling was based on the timestamps of births of all the piglets in a litter and each piglet vitality score based on the number of times a piglet attempts to stand within the 1st minute after birth. Data labeling was performed 1 h before the start of parturition until 0.5 h after the end of parturition. The depth images were processed to segment the piglets, and a developed parametrized ellipse-fitting algorithm performed piglet detection by multi-ellipse fitting. Piglet count and count tracking were established by the number of fitted ellipses on the image-object shape. Each sequential increment in the piglet count was used to compute the inter-birth interval. The developed model attained a detection accuracy of 0.832 for no piglets and 0.801 for 14 piglets in a range of 0 to 14 piglets in a litter. In piglet counting and count tracking, the model achieved an average accuracy of 0.918 (R2) at an RMSE of 1.225 piglets. For the classification of an asphyxia event, the model indicated an accuracy of 0.863, specificity of 0.921, precision of 0.791, and a sensitivity of 0.723. The developed system can serve as part of Precision Livestock Farming automatic farrowing monitoring system with the aim of detecting the start of parturition, piglet count tracking, and asphyxia occurrence.

Proteomic analysis of adipose tissue during the last weeks of gestation in pure and crossbred Large White or Meishan fetuses gestated by sows of either breed

BackgroundThe degree of adipose tissue development at birth may influence neonatal survival and subsequent health outcomes. Despite their lower birth weights, piglets from Meishan sows (a fat breed with excellent maternal ability) have a higher survival rate than piglets from Large White sows (a lean breed). To identify the main pathways involved in subcutaneous adipose tissue maturation during the last month of gestation, we compared the proteome and the expression levels of some genes at d 90 and d 110 of gestation in purebred and crossbred Large White or Meishan fetuses gestated by sows of either breed.ResultsA total of 52 proteins in fetal subcutaneous adipose tissue were identified as differentially expressed over the course of gestation. Many proteins involved in energy metabolism were more abundant, whereas some proteins participating in cytoskeleton organization were reduced in abundance on d 110 compared with d 90. Irrespective of age, 24 proteins differed in abundance between fetal genotypes, and an interaction effect between fetal age and genotype was observed for 13 proteins. The abundance levels of proteins known to be responsive to nutrient levels such as aldolase and fatty acid binding proteins, as well as the expression levels of FASN, a key lipogenic enzyme, and MLXIPL, a pivotal transcriptional mediator of glucose-related stimulation of lipogenic genes, were elevated in the adipose tissue of pure and crossbred fetuses from Meishan sows. These data suggested that the adipose tissue of these fetuses had superior metabolic functionality, whatever their paternal genes. Conversely, proteins participating in redox homeostasis and apoptotic cell clearance had a lower abundance in Meishan than in Large White fetuses. Time-course differences in adipose tissue protein abundance were revealed between fetal genotypes for a few secreted proteins participating in responses to organic substances, such as alpha-2-HS-glycoprotein, transferrin and albumin.ConclusionsThese results underline the importance of not only fetal age but also maternal intrauterine environment in the regulation of several proteins in subcutaneous adipose tissue. These proteins may be used to estimate the maturity grade of piglet neonates.

The Changes of Fecal Steroid Hormones and Bacterial Composition in Different Gestation Stages of Meishan Sows

Currently, the importance of gut microbiota to the health of their host has been well discussed, yet the knowledge about the host hormonal effect on the gut microbiota is limited. In this study, a combination of the high-throughput 16S rRNA gene-based pyrosequencing and the Mass Spectrometry (MS)-based metabolomics techniques were used to investigate the stool microbial composition and microbial metabolites at different gestation day in Meishan sows. The results showed that, the stool steroid hormones including estradiol (E2), progesterone (P4) and cortisol (CORT) were increased at gestation day 90 (P<0.05), when compared to gestation day 30. In coincide with the changes of steroid hormones, the relative abundance of Burkholderiales and Selenomonadales of the stool microbiota at d90 of pregnancy was significantly increased than that of at d30 of pregnancy at the order level (P<0.05). However, no significant difference of the richness estimators (ACE and Chao), and the diversity indices (Shannon and Simpson) were found between the d30 and d90 of gestation. Further, the metabolomics profile revealed 13 metabolites changed greatly from the gestation day 30 to 90, including amino acid metabolic pathway, lipid and carbohydrate metabolic pathway (P<0.001). The results suggest that the interaction of the steroid hormones and the gut bacteria may account for the metabolic changes throughout the length of pregnancy.

Moderate Maternal Energy Restriction During Gestation in Pigs Attenuates Fetal Skeletal Muscle Development Through Changing Myogenic Gene Expression and Myofiber Characteristics.

Maternal undernutrition during gestation influences the development of the fetus, thereby increasing the risk of metabolic syndrome in adulthood. Skeletal muscle, one of the key insulin-responsive organs, is susceptible to maternal nutritional programming. This study aimed to evaluate the effect of moderate maternal energy restriction during gestation in pigs on basic events of fetal skeletal myogenesis. Primiparous, purebred Meishan sows were fed a control (normal energy intake) or a low-energy (LE) diet from mating to day 90 of gestation. Biochemical characteristics, myogenic gene expression, and myofiber characteristics were assessed in longissimus dorsi (LD) muscle of fetuses on days 55 and 90 of gestation. Fetal weights, myofiber density, and fetal umbilical vein serum triiodothyronine (T3) concentration decreased in LE group on both days 55 and 90 of gestation. The expression and activity of creatine kinase, the messenger RNA (mRNA) expression of myosin heavy chain ( MYH/ MyHC) genes ( MYH2 and MYH4), concentration of muscular DNA and protein, and protein expression of fast-MyHC isoforms were reduced in LD muscle of LE fetuses on day 55 or 90 of gestation. Meanwhile, myogenic gene expression was reduced in LE fetuses on day 55 or 90 of gestation, indicating the downregulation of myogenesis. Additionally, the exposure to LE diet led to increased isocitrate dehydrogenase activity and slow MyHC (MYH7) mRNA expression on day 90 of gestation, suggesting the elevation of oxidative muscle metabolism. These findings suggest that moderate energy restriction during gestation attenuates fetal skeletal muscle development in pigs, resulting in the delay of skeletal muscle differentiation and maturity.

P3013 Characterization of endometrium protein expression during mid-late gestation in Meishan and Duroc sows with iTRAQ analysis

P3013 Characterization of endometrium protein expression during mid-late gestation in Meishan and Duroc sows with iTRAQ analysis