Probiotic Lactobacillus rhamnosus GG improves insulin sensitivity and offspring survival via modulation of gut microbiota and serum metabolite in a sow model.

BACKGROUND: Sows commonly experience insulin resistance in late gestation and lactation, causing lower feed intake and milk production, which can lead to higher mortality rates in newborn piglets. The probiotic Lactobacillus rhamnosus GG (LGG) is known to improve insulin resistance. However, whether supplementing LGG can improve insulin sensitivity in sows and enhance lactation performance, particularly the early survival of offspring remains unclear. Hence, we explored the effects and mechanisms of supplementing LGG during late gestation and lactation on sow insulin sensitivity, lactation performance, and offspring survival. In total, 20 sows were randomly allocated to an LGG (n = 10) and control group (n = 10). RESULTS: In sows, LGG supplementation significantly improved insulin sensitivity during late gestation and lactation, increased feed intake, milk production and colostrum lactose levels in early lactation, and enhanced newborn piglet survival. Moreover, LGG treatment significantly reshaped the gut microbiota in sows, notably increasing microbiota diversity and enriching the relative abundance of insulin sensitivity-associated probiotics such as Lactobacillus, Bifidobacterium, and Bacteroides. Serum metabolite and amino acid profiling in late-gestation sows also revealed decreased branched-chain amino acid and kynurenine serum levels following LGG supplementation. Further analyses highlighted a correlation between mitigated insulin resistance in late pregnancy and lactation by LGG and gut microbiota reshaping and changes in serum amino acid metabolism. Furthermore, maternal LGG enhanced immunity in newborn piglets, reduced inflammation, and facilitated the establishment of a gut microbiota. CONCLUSIONS: We provide the first evidence that LGG mitigates insulin resistance in sows and enhances offspring survival by modulating the gut microbiota and amino acid metabolism.

A Gestational Pectin Diet Could Improve the Health of Multiparous Sows by Modulating the Gut Microbiota and Cytokine Level during Late Pregnancy.

This study aimed to investigate the effects of the dietary fiber pectin on the gut microbiota and health of parturient sows. A total of 30 parity 5-7, multiparous gestation sows (Large White × Landrace) were randomly assigned to two treatment groups after mating: Con (control, basic diet) and Pec (pectin, 3%). The sows received the two diets during gestation, and all sows were fed the same standard basic diet during lactation. The results of ß-diversity showed that the composition of the gut microbiota was different in the Con and Pec groups. Compared with the sows in the Con group, the Pec sows showed a higher abundance of the gut bacteria Clostridium and Romboutsia and a lower abundance of harmful bacteria (Micrococcaceae, Coriobacteriaceae, Dorea, Actinomyces). On the other hand, the SCFA plasma concentration was increased in the Pec group, while pro-inflammatory cytokine (IL-6, IL-1ß, and TNF-α) concentrations were decreased. In conclusion, the soluble dietary fiber pectin could improve the reproductive performance and health of sows by increasing the abundance of some commensal bacteria enhancing the metabolite SCFA levels and reducing the pro-inflammatory cytokine plasma levels.

Benefits of maternal pectin supplementation in gestation diet on vaginal microbiota of sows and intestinal health of newborn piglets.

Pectin is a proven prebiotic and widely used in human health products. This study aims to assess the impact of dietary pectin supplementation during gestation on sow vaginal microbiota and the offspring's intestinal composition. Thirty sows were randomly allocated to two groups and fed a standard diet (CON) or a standard diet supplemented with 3 g/kg pectin (PEC). Blood, feces, and vaginal swab samples from the sows and blood, intestines issue, and colonic content samples from the offspring were collected and analyzed. The results indicate that the relative abundance of vaginal Lactobacillus was notably enhanced in the PEC group and fecal ß-glucuronidase (ß-G) activity and plasma 17ß-estradiol (E2) concentration were also significantly increased in the PEC group. Newborn piglets were found to host different microbial communities as well. At the phylum level, Proteobacteria dominated in the CON group, and Firmicutes was predominant in the PEC group. Newborn piglets in the PEC group had a lower interleukin-6 (IL-6) concentration in their plasma. The expression of intestinal cytokines of offspring was improved as well. Villus height and villus height/crypt depth (V/C) in the PEC group were extremely higher than those in the CON group. In conclusion, dietary pectin supplementation can be of benefit to both sows and newborn piglets.

Improvement of insulin sensitivity by dietary fiber consumption during late pregnant sows is associated with gut microbiota regulation of tryptophan metabolism.

BACKGROUND: Dietary fiber (DF) consumption was reported to improve insulin sensitivity, change the tryptophan metabolism, and alter the gut microbiota. Herein, this study aimed to investigate the effects of DF consumption on insulin sensitivity, tryptophan metabolism, and gut microbiota composition in sows during late pregnancy, and explore the relationship between tryptophan metabolites and insulin sensitivity regulated by DF supplementation. RESULTS: Twelve sows were randomly assigned to two dietary treatment groups (six/group): the low-fiber (LF) group, which was fed a basal diet, and the high-fiber (HF) group, which was fed the basal diet supplemented with 22.60 g/kg inulin and 181.60 g/kg cellulose. During late pregnancy, meal test, glucose tolerance test, and insulin challenge test were used to investigate the insulin sensitivity of sows, using the percutaneous brachiocephalic vein catheterization technique. High DF consumption resulted in improved insulin sensitivity, especially during the second and third trimesters, and promoted serotonin production from tryptophan. Additionally, plasma serotonin concentration was positively correlated with the insulin sensitivity index during late pregnancy. Moreover, DF consumption elevated fecal short-chain fatty acid (SCFA) concentrations, altered fecal microbial diversity, and increased the abundances of Rikenellaceae_RC9_gut_group, Alloprevotella, Parabacteroides, Roseburia, and Sphaerochaeta, which were positively correlated to plasma serotonin concentration. CONCLUSIONS: DF consumption improved insulin sensitivity during late pregnancy in sows, which improved microbial diversity in fecal samples and increased fecal SCFA concentrations, resulting in a positive correlation with plasma serotonin level.

Standardized ileal digestibility of amino acids in Chinese fermented soybean meal from different sources fed to mid and late-gestating sows.

We determined apparent ileal digestibility (AID) and standardized ileal digestibility (SID) values of crude protein (CP) and amino acids (AA) in fermented soybean meal from five different sources (FSBM 1 to 5) in China when fed to mid and late-gestating sows. Twenty-four parity four sows (12 at 30 d in gestation and 12 at 80 d in gestation) were fitted with a T-cannula in the distal ileum and used in this experiment. Sows were randomly assigned to a replicated 6 × 3 Youden square design including six diets and three periods. Six diets were provided for sows in mid and late gestation, including a nitrogen-free diet and five test diets containing 26% FSBM from different sources. Results showed that there were differences in AID and SID of CP among the different FSBM samples, but no differences between sow physiological stages were observed. Specifically, when mid-gestating sows were fed FSBM 2, the AID of CP was the lowest, whereas FSBM 3 exhibited a greater AID of CP when compared to the other FSBM samples (P < 0.01). Furthermore, during late gestation, FSBM 3 consistently had greater SID of CP when compared to other FSBM samples (P < 0.01). The ileal digestibility of most AA varied with different FSBM samples. In both mid and late gestation, differences (P < 0.05) were observed for AID of lysine, tryptophan, histidine, and arginine across different FSBM samples. Similarly, the AID of dispensable AA (cysteine, glutamine, and serine) also exhibited differences (P < 0.05) across different FSBM samples in both mid and late-gestating sows. For mid-gestating sows, SID differences relating to lysine, phenylalanine, tryptophan, threonine, and arginine were observed among different diets (P < 0.05). In late-gestating sows, SID values for lysine, tryptophan, leucine, and arginine differed across diets (P < 0.05). Furthermore, the ileal digestibility of some dispensable AA was influenced by physiological stage, as evidenced by greater AID and SID values for glycine, glutamine, cysteine, and serine in late-gestating sows when compared to mid-gestating sows (P < 0.01). In summary, our study determined AA ileal digestibility of different FSBM fed to mid and late-gestating sows. We observed that the AA ileal digestibility differed among five FSBM samples, but the physiological stage of sows did not affect the ileal digestibility of CP and most AA. Additionally, when formulating diets for sows, it is crucial to consider the nutritional value differences of FSBM.

Fermented soybean meal (FSBM) is obtained from the microbial fermentation of soybean meal, which reduces anti-nutritional factor levels and enhances other nutrient content. Substituting soybean meal with FSBM in piglet and growing pig diets improves nutrient digestibility. However, its nutritional value for sows remains unclear. Therefore, five sources of FSBM were fed to sows in mid and late gestation to evaluate apparent ileal digestibility (AID) and standardized ileal digestibility (SID) values of amino acids (AA). We found that different FSBM samples impacted the SID value of AA when fed to gestating sows. Additionally, sow physiological stage influenced the SID of some dispensable AA. These findings provide valuable insights into the incorporation of FSBM into sow diets.

Zearalenone Decreases Food Intake by Disrupting the Gut-Liver-Hypothalamus Axis Signaling via Bile Acids.

Zearalenone (ZEN) is a mycotoxin that is harmful to humans and animals. In this study, female and male rats were exposed to ZEN, and the results showed that ZEN reduced the farnesoid X receptor (FXR) expression levels in the liver and disrupted the enterohepatic circulation of bile acids (BAs). A decrease in food intake induced by ZEN was negatively correlated with an increase in the level of total BAs. BA-targeted metabolomics revealed that ZEN increased glycochenodeoxycholic acid levels and decreased the ratio of conjugated BAs to unconjugated BAs, which further increased the hypothalamic FXR expression levels. Preventing the increase in total BA levels induced by ZEN via Lactobacillus rhamnosus GG intervention restored the appetite. In conclusion, ZEN disrupted the enterohepatic circulation of BAs to decrease the level of food intake. This study reveals a possible mechanism by which ZEN affects food intake and provides a new approach to decrease the toxic effects of ZEN.

Selenomethionine alleviates chronic heat stress-induced breast muscle injury and poor meat quality in broilers via relieving mitochondrial dysfunction and endoplasmic reticulum stress.

In the present study, the chronic heat stress (CHS) broiler model was developed to investigate the potential protection mechanism of organic selenium (selenomethionine, SeMet) on CHS-induced skeletal muscle growth retardation and poor meat quality. Four hundred Arbor Acres male broilers (680 ± 70 g, 21 d old) were grouped into 5 treatments with 8 replicates of 10 broilers per replicate. Broilers in the control group were raised in a thermoneutral environment (22 ± 2 °C) and fed with a basal diet. The other four treatments were exposed to hyperthermic conditions (33 ± 2 °C, 24 h in each day) and fed on the basal diet supplied with SeMet at 0.0, 0.2, 0.4, and 0.6 mg Se/kg, respectively, for 21 d. Results showed that CHS reduced (P < 0.05) the growth performance, decreased (P < 0.05) the breast muscle weight and impaired the meat quality of breast muscle in broilers. CHS induced protein metabolic disorder in breast muscle, which increased (P < 0.05) the expression of caspase 3, caspase 8, caspase 9 and ubiquitin proteasome system related genes, while decreased the protein expression of P-4EBP1. CHS also decreased the antioxidant capacity and induced mitochondrial stress and endoplasmic reticulum (ER) stress in breast muscle, which increased (P < 0.05) the ROS levels, decreased the concentration of ATP, increased the protein expression of HSP60 and CLPX, and increased (P < 0.05) the expression of ER stress biomarkers. Dietary SeMet supplementation linearly increased (P < 0.05) breast muscle Se concentration and exhibited protective effects via up-regulating the expression of the selenotranscriptome and several key selenoproteins, which increased (P < 0.05) body weight, improved meat quality, enhanced antioxidant capacity and mitigated mitochondrial stress and ER stress. What's more, SeMet suppressed protein degradation and improved protein biosynthesis though inhibiting the caspase and ubiquitin proteasome system and promoting the mTOR-4EBP1 pathway. In conclusion, dietary SeMet supplementation increases the expression of several key selenoproteins, alleviates mitochondrial dysfunction and ER stress, improves protein biosynthesis, suppresses protein degradation, thus increases the body weight and improves meat quality of broilers exposed to CHS.

Effects of maternal methyl donor intake during pregnancy on ileum methylation and function in an intrauterine growth restriction pig model.

BACKGROUND: Intrauterine growth retardation (IUGR) affects intestinal growth, morphology, and function, which leads to poor growth performance and high mortality. The present study explored whether maternal dietary methyl donor (MET) supplementation alleviates IUGR and enhances offspring's growth performance by improving intestinal growth, function, and DNA methylation of the ileum in a porcine IUGR model. METHODS: Forty multiparous sows were allocated to the control or MET diet groups from mating until delivery. After farrowing, 8 pairs of IUGR and normal birth weight piglets from 8 litters were selected for sampling before suckling colostrum. RESULTS: The results showed that maternal MET supplementation tended to decrease the IUGR incidence and increased the average weaning weight of piglets. Moreover, maternal MET supplementation significantly reduced the plasma concentrations of isoleucine, cysteine, urea, and total amino acids in sows and newborn piglets. It also increased lactase and sucrase activity in the jejunum of newborn piglets. MET addition resulted in lower ileal methionine synthase activity and increased betaine homocysteine S-methyltransferase activity in the ileum of newborn piglets. DNA methylation analysis of the ileum showed that MET supplementation increased the methylation level of DNA CpG sites in the ileum of newborn piglets. Down-regulated differentially methylated genes were enriched in folic acid binding, insulin receptor signaling pathway, and endothelial cell proliferation. In contrast, up-regulated methylated genes were enriched in growth hormone receptor signaling pathway and nitric oxide biosynthetic process. CONCLUSIONS: Maternal MET supplementation can reduce the incidence of IUGR and increase the weaning litter weight of piglets, which may be associated with better intestinal function and methylation status.

Revealing the mechanism of fiber promoting sow embryo implantation by altering the abundance of uterine fluid proteins: A proteomic perspective.

Many studies have shown that fiber in the diet plays an important role in improving the reproductive performance of sows, but there is rarely research on the impact of fiber on early embryo implantation. This study used 4D-Label free technology to identify and analyze the effect of the fiber composition in the diet on the protein in the early pregnancy uterine fluid (UF) of sows. The results indicate that ratio of insoluble fibers to soluble fibers (ISF/SF) 4.89 can increase the concentration of progesterone (PROG) and reduce tumor necrosis factorα (TNF-α) concentration in sow UF. In addition, through 4D-Label free, we identified a total of 4248 proteins, 38 proteins abundance upregulated and 283 proteins abundance downregulated in UF. Through enrichment analysis of these differential abundance proteins (DAPs), it was found that these differential proteins are mainly related to the docking of extracellular vesicles, vesicular transport, inflammatory response, and insulin resistance. Therefore, the results of this study reveal the possible mechanism by which fiber improves the reproductive performance of sows, laying a theoretical foundation for future research on the effects of diet on reproduction. SIGNIFICANCE: This study demonstrates the importance of dietary fiber for early embryo implantation in sows. The effect of dietary ISF/SF on early embryo implantation in sows was elucidated from a proteomic perspective through 4D-Label free technology. This study not only has significant implications for improving sow reproductive efficiency, but also provides important theoretical references for studying early miscarriage and reproductive nutrition in human pregnancy.

Microbial Mechanistic Insight into the Role of Yeast-Derived Postbiotics in Improving Sow Reproductive Performance in Late Gestation and Lactation Sows.

The purpose of this study is to investigate the effects of supplementing Yeast-derived postbiotics (Y-dP) to the diet of sows during late pregnancy and lactation on fecal microbiota and short-chain fatty acids (SCFA) in sows and their offspring weaned piglets, as well as the relationship between gut microbiota and SCFA, serum cytokines, and sow reproductive performance. A total of 150 sows were divided into three groups: control diet (CON), CON + Y-dP 1.25 g/kg, and CON + Y-dP 2 g/kg. The results showed that supplementing 0.125% Y-dP to the diet of sows can increase the content of isobutyric acid (IBA) in the feces of pregnant sows and reduce the content of butyric acid (BA) in the feces of weaned piglets (p < 0.05). The fecal microbiota of pregnant sows ß diversity reduced and piglet fecal microbiota ß diversity increased (p < 0.05). Y-dP significantly increased the abundance of Actinobacteria and Limosilactobacilli in the feces of pregnant sows (p < 0.05), as well as the abundance of Verrucomicrobiota, Bacteroidota, and Fusobacteriota in the feces of piglets (p < 0.05). The abundance of Bacteroidota in the feces of pregnant sows is positively correlated with propionic acid (PA) (r > 0.5, p < 0.05). The abundance of Prevotellaceae_NK3B31_group was positively correlated with Acetic acid (AA), PA, Valerate acid (VA), and total volatile fatty acid (TVFA) in the feces of pregnant sows (r > 0.5, p < 0.05), and Bacteroidota and Prevotellaceae_NK3B31_group were negatively correlated with the number of stillbirths (r < -0.5, p < 0.05). The abundance of Lactobacillus and Holdemanella in piglet feces was positively correlated with TVFA in feces and negatively correlated with IgA in serum (r > 0.5, p < 0.05). In conclusion, supplementing Y-dP to the diet of sows from late gestation to lactation can increase the chao1 index and α diversity of fecal microorganisms in sows during lactation, increase the abundance of Actinobacteria and Limosilactobacilli in the feces of sows during pregnancy, and increase the abundance of beneficial bacteria such as Bacteroidetes in piglet feces, thereby improving intestinal health. These findings provide a reference for the application of Y-dP in sow production and a theoretical basis for Y-dP to improve sow production performance.

Amino acid standardized ileal digestibility together with concentrations of digestible and metabolizable energy in Saccharomyces cerevisiae yeast and soybean meal for gestating sows.

The standardized ileal digestibility (SID) of amino acids (AAs) plus crude protein (CP), in addition to digestible energy (DE) and metabolizable energy (ME) concentrations, was assessed through two experiments on Saccharomyces cerevisiae yeast (SCY) combined with soybean meal (SBM) for gestating sows. SCY and SBM were subjected to experiment 1 for the determination of CP and AAs in terms of SID. Under a randomized complete block design, three dietary treatments were provided for a total of 24 Landrace × Yorkshire gestating sows (parity 2), with the distal ileum clipped by a T-cannula at gestational day 33 based on body weight (BW) (194.1 ±â€…7.1, 195.3 ±â€…8.5, and 195.3 ±â€…8.6 kg). SCY and SBM were used as the only source of nitrogen to prepare two semi-purified diets and a nitrogen-free diet was also utilized to examine CP plus AAs for basal ileal endogenous losses. The gestating sows were initially fed these diets for 5 d to allow for adaptation, and ileal digesta was collected 2 d later for analysis. CP and all AAs in SCY, except for Trp and Gly, showed significantly lower SID than those in SBM (P < 0.05). Among the essential AAs, the range of SID was 68.8% for Thr to 92.2% for Arg in dried yeast, and from 79.9% for Thr to 98.6% for Met in SBM. DE plus ME were measured via experiment 2 with a randomized complete block design on SCY and SBM. Eighteen day-35 Landrace × Yorkshire pregnant sows (parity 3) were allocated to three diets based on BW (233.3 ±â€…16.0, 233.4 ±â€…9.6, and 233.4 ±â€…10.3 kg). Three diets were adopted for the experiment, namely, a corn-based diet as well as two diets containing 20.2% SCY and 20.0% SBM samples. The full fecal collection method, comprising a 5-day adaptation period before a 5- to 6-d experimental period for quantitative urine and feces collection, was employed for metabolic trials. The DE and ME for SCY were remarkably decreased compared with those for SBM (3812 kcal/kg DM vs. 4264 kcal/kg DM and 3714 kcal/kg DM vs. 4157 kcal/kg DM), respectively (P < 0.05). No differences were observed in the apparent total tract digestibility (ATTD) of organic matter, CP, and gross energy between SCY and SBM, but ATTD was significantly reduced in SCY for acid detergent fiber, dry matter, and neutral detergent fiber by contrast with SBM (P < 0.05). In conclusion, most AAs and CP in SCY had lower SID, DE, and ME than SBM in this study. These findings can be applied to diet formulation with the aforementioned ingredients for sows.

Saccharomyces cerevisiae yeast (SCY) is commonly used as an additive in feed (<1% of the formulation), but there is a limited amount of available information about its function as a promising source of proteins for pig diets, and especially, the nutritive value of yeast protein for gestating sows remains to be clarified. Feeding stuff has different digestibility between growing and gestating pigs. Therefore, our study evaluated the standardized ileal digestibility of amino acids and crude protein together with metabolizable and digestible energy in SCY for gestating sows, to provide nutritional value parameters on its potential as an effective alternative to traditional protein ingredients such as soybean meal in sow diet formulations.

Maternal folic acid and vitamin B12 supplementation during medium to late gestation promotes fetal development via improving placental antioxidant capacity, angiogenesis and amino acid transport.

BACKGROUND: Folic acid and vitamin B12 (FV), being B vitamins, not only facilitate the remethylation of homocysteine (Hcy) but also contribute to embryonic development. This study aimed to assess the impact of FV supplementation during late pregnancy on sows' reproductive performance, amino acid metabolism, placental angiogenesis, and related parameters. Twenty primiparous sows at day 60 of gestation were randomly allocated to two groups: a basal diet (CON) group and a group receiving a basal diet supplemented with folic acid at 20 ppm and vitamin B12 at 125 ppb. RESULTS: The findings revealed that dietary FV supplementation significantly reduced the incidence of intrauterine growth retardation compared to the CON group (P < 0.05). Furthermore, it led to a decrease in the Hcy levels in umbilical cord serum (P < 0.05) and activation of the placental mechanistic target of rapamycin complex 1 (mTORC1) signaling pathway (P < 0.05). Additionally, FV supplementation lowered placental malondialdehyde levels (P < 0.05) and increased the expression of placental thioredoxin (P = 0.05). Moreover, maternal FV supplementation notably elevated placental vascular density (P < 0.05) and the expression of sodium-coupled neutral amino acid transporter 2 (SNAT2) (P < 0.05), as well as amino acid concentrations in umbilical cord blood (P < 0.05). CONCLUSION: Maternal FV supplementation during medium to late gestation reduced Hcy levels in umbilical cord blood and positively impacted fetal development. This improvement was closely associated with increased placental antioxidant capacity and vascular density, as well as activation of the placental mTORC1-SNAT2 signaling pathway. © 2023 Society of Chemical Industry.

Chromium propionate supplementation to energy- and protein-reduced diets reduces feed consumption but improves feed conversion ratio of yellow-feathered male broilers in the early period and improves meat quality.

Growth performance and carcass traits may be retarded by low nutrient density diets. Organic chromium propionate (CrProp) can improve growth, carcass traits, and meat quality in farmed lambs, white broilers, and fish. Limited data regarding CrProp's impacts on yellow-feathered broilers are available. Eight hundred yellow-feathered male broilers (1-day old) were randomly allocated to 4 dietary groups and reared for 56 d. The trial was a 2 (dietary nutrient density) ×2 (CrProp) factorial arrangement with 4 diets: regular nutrient diet and low nutrient density (LND, reduction in metabolizable energy by 81 kcal and crude protein by 0.43%) diet supplemented with or without 200 mg/kg CrProp. Broilers were euthanized at d 56 after blood collection. The results indicated that the LND diet led to greater average daily feed intake (ADFI) from d 1 to 42 and feed conversion ratio (FCR) from d 22 to 42 (P < 0.05). Supplementation of CrProp improved body weight (BW) from d 1 to 56, average daily gain (ADG), and FCR during d 1 to 42 but reduced ADFI during d 1 to 21, as well as lowered abdominal fat percentage (P < 0.05). Supplementation with CrProp to regular and LND diets reduced ADFI but improved FCR from d 1 to 21 (P < 0.05). The LND diet lowered total antioxidant capacity (T-AOC) concentration and total superoxide dismutase (T-SOD) activity in the jejunal mucosa. CrProp elevated T-AOC levels and glutathione peroxidase activity (GSH-Px, P < 0.05). Dietary CrProp upregulated (P < 0.05) the expression of fatty acid transporter (FABP1) gene and peptide transporter (Pept1) gene. CrProp administration increased jejunal FABP1 expression and lowered cooking loss of breast meat (P < 0.05) in the LND group while reducing shear force (P = 0.009) of broilers treated by regular diet. In summary, CrProp administration to the LND diet can improve growth performance in the starter period and meat quality on d 56, possibly through upregulated nutrient transporter gene expression in the jejunum and enhanced antioxidant capability.

Generation of Porcine Angiogenin 4-Expressing Pichia pastoris and Its Protection against Intestinal Inflammatory Injury.

Antimicrobial peptides have been extensively studied as potential alternatives to antibiotics. Porcine angiogenin 4 (pANG4) is a novel antimicrobial peptide in the angiogenin (ANG) family, which may have a regulatory effect on intestinal microflora. The object of present study is obtained pANG4 protein by heterologous expression, so as to explore the biological function of recombinant pANG4 (rpANG4). The pANG4 was expressed in Pichia pastoris (P. pastoris) and anti-inflammatory effects were investigated in intestinal porcine epithelial cell line-J2 (IPEC-J2) and mice. Purified rpANG4 had bacteriostatic activity and did not cause hemolysis or cytotoxicity at concentrations below 128 µg/mL. Purified rpANG4 increased the activity of IPEC-J2 and reduced apoptosis in vitro. rpANG4 reduced the pro-inflammatory gene expression and upregulated tight junction protein gene expression during inflammation. rpANG4 alleviated lipopolysaccharide (LPS)-induced liver and spleen damage, intestinal inflammation, jejunal apoptosis genes' expression, and improved immune function in an in vivo mice model. rpANG4 increased tight junction protein gene expression in jejunum, thereby improving the jejunum intestinal barrier function. In conclusion, rpANG4 had antibacterial activity, inhibited intestinal inflammation, improved intestinal barrier function, and alleviated liver and spleen damage. The current study contributes to the development of antibiotic substitutes and the improvement of animal health.

Bile acids metabolism in the gut-liver axis mediates liver injury during lactation.

AIMS: The obesity epidemic, especially in pregnant women, linked to a higher risk of liver diseases. Bile acids (BAs) are known to participate in liver metabolism, but this function during obesogenic reproductive process remains largely uncertain. The study aims to identify whether a high-fat diet (HFD) during pregnancy negatively disturbs liver metabolism and the potential role of BAs and gut microbiota (GM)in a sow model. MAIN METHODS: Reproductive (RP) or non-reproductive (NRP) sows were fed a 15 % HFD containing compound oil. Body condition, blood parameters, and BAs levels/profile during gestation and lactation were monitored. The tissues and colonic GM were collected after euthanasia at the end of lactation. HepG2 hepatocytes were used to test the effects of BAs on liver damage and the mechanism. KEY FINDINGS: Reproductive sows fed an HFD (HF-RP) experienced increased weight loss, and elevated plasma non-esterified fatty acid (NEFA) during lactation, consistent with exacerbated lipolysis, aggravating the risk of liver damage. HF-RP sows exhibited an enlarged BAs pool size and alterations in composition (higher levels of CDCA and LCA species) along with a drastic change in the GM (increased Firmicutes/Bacteroidetes ratio and declined Lactobacillus abundance). Furthermore, the liver FXR-SHP pathway, BAs synthesis and transport underwent adaptive regulation to sustain the BAs homeostasis and hepatic lipid metabolism. CDCA alleviated endoplasmic reticulum (ER) stress induced by palmitic acid via FXR pathway, in HepG2 cells. SIGNIFICANCE: Lactation BAs metabolism signal in gut-liver axis coordinated the risk of liver damage induced by exacerbated lipolysis in obesogenic pregnancy.

Partial Substitution of Whey Protein Concentrate with Spray-Dried Porcine Plasma or Soy Protein Isolate in Milk Replacer Differentially Modulates Ileal Morphology, Nutrient Digestion, Immunity and Intestinal Microbiota of Neonatal Piglets.

Appropriate protein sources are vital for the growth, development and health of neonates. Twenty-four 2-day-old piglets were randomly divided into three groups and fed isoenergetic and isonitrogenous diets. The experimental diets included a milk replacer with 17.70% whey protein concentrate (WPC group), a milk replacer with 6% spray-dried porcine plasma isonitrogenously substituting WPC (SDPP group), and a milk replacer with 5.13% soy protein isolate isonitrogenously substituting WPC (SPI group). Neonatal piglets were fed milk replacer from postnatal day 2 (PND 2) to day 20 (PND 20). The growth performance, intestinal morphology, activities of digestive enzymes, plasma biochemical parameters, immunity-related genes, short-chain fatty acids (SCFA) and intestinal microbiota in the colonic chyme were determined. The results showed that SDPP-fed piglets had higher final BW (p = 0.05), ADG (p = 0.05) and F/G (p = 0.07) compared with WPC- and SPI-fed piglets, and SDPP-fed piglets had a lower diarrhea index (p < 0.01) from PND 2 to PND 8. SDPP-fed piglets had an increased ileal villus height (p = 0.04) and ratio of villus height to crypt depth (VCR) (p = 0.02), and increased activities of sucrase (p < 0.01), lactase (p = 0.02) and trypsin (p = 0.08) in the jejunum, compared with WPC- and SPI-fed piglets. Furthermore, SPI-fed piglets had an increased mRNA expression of IL-6 (p < 0.01) and concentration of plasma urea (p = 0.08). The results from LEfSe analysis showed that SDPP-fed piglets had a higher abundance of beneficial Butyricicoccus compared with WPC- and SPI-fed piglets, in which higher abundances of pathogenic bacteria such as Marinifilaceae, Fusobacterium and Enterococcus were observed. Moreover, SDPP-fed piglets had an increased concentration of butyric acid (p = 0.08) in the colonic chyme compared with WPC- and SPI-fed piglets. These results suggest that neonatal piglets fed milk replacer with SDPP partially substituting WPC had improved growth performance and intestinal morphology and function, associated with higher digestive enzyme activity and fewer pathogenic bacteria.

Acute Endoplasmic Reticulum Stress Suppresses Hepatic Gluconeogenesis by Stimulating MAPK Phosphatase 3 Degradation.

Drug-induced liver injury (DILI) is a widespread and harmful disease, and is closely linked to acute endoplasmic reticulum (ER) stress. Previous reports have shown that acute ER stress can suppress hepatic gluconeogenesis and even leads to hypoglycemia. However, the mechanism is still unclear. MAPK phosphatase 3 (MKP-3) is a positive regulator for gluconeogenesis. Thus, this study was conducted to investigate the role of MKP-3 in the suppression of gluconeogenesis by acute ER stress, as well as the regulatory role of acute ER stress on the expression of MKP-3. Results showed that acute ER stress induced by tunicamycin significantly suppressed gluconeogenesis in both hepatocytes and mouse liver, reduced glucose production level in hepatocytes, and decreased fasting blood glucose level in mice. Additionally, the protein level of MKP-3 was reduced by acute ER stress in both hepatocytes and mouse liver. Mkp-3 deficiency eliminated the inhibitory effect of acute ER stress on gluconeogenesis in hepatocytes. Moreover, the reduction effect of acute ER stress on blood glucose level and hepatic glucose 6-phosphatase (G6pc) expression was not observed in the liver-specific Mkp-3 knockout mice. Furthermore, activation of protein kinase R-like ER kinase (PERK) decreased the MKP-3 protein level, while inactivation of PERK abolished the reduction effect of acute ER stress on the MKP-3 protein level in hepatocytes. Taken together, our study suggested that acute ER stress could suppress hepatic gluconeogenesis by stimulating MKP-3 degradation via PERK, at least partially. Thus, MKP-3 might be a therapeutic target for DILI-related hypoglycemia.

Effect of heating, microbial fermentation, and enzymatic hydrolysis of soybean meal on growth performance, nutrient digestibility, and intestinal microbiota of weaned piglets.

The macromolecular proteins, anti-nutritional factors, and allergens contained in soybean meal (SBM) have a negative impact on the growth of weaned piglets. The objective of this study was to investigate the effects of heating, microbial fermentation, and enzymatically hydrolyzed SBM on the growth performance, nutrient digestibility, serum biochemistry, intestinal morphology, volatile fatty acids, and microbiota of weaned piglets. After the preparation of soaked SBM (SSBM), enzymatically hydrolyzed SBM (ESBM), and microbial fermented and enzymatically hydrolyzed SBM (MESBM), 72 weaned piglets were randomly allocated to three groups for a 21-d trial. In the three groups, 17% of conventional SBM in basal corn-soybean meal diet was replaced by an equivalent amount of SSBM (control group), ESBM, or MESBM. The results showed that the contents of glycinin, ß-conglycinin, trypsin inhibitor, and proteins above 20 kDa were significantly decreased in ESBM and MESBM, compared with SSBM, and the surface of ESBM and MESBM had more pores and fragmented structure. In the second week and throughout the entire experimental period, the diarrhea index was reduced (P < 0.01) in ESBM and MESBM in contrast with SSBM. Furthermore, the inclusion of ESBM and MESBM in the diet improved the apparent total tract digestibility of dry matter and crude protein (P < 0.05), and increased the abundances of the genera Lactobacillus and Clostridium_sensu_stricto_1, respectively. Metagenomic sequencing further identified that members of six species of Proteobacteria, four species of Clostridiales, and three species of Negativiautes were enriched in the colon of piglets fed MESBM, while two bacterial species, Lachnoclostridium and Lactobacillus_points, were enriched in the colon of piglets fed ESBM. In conclusion, replacing SSBM with ESBM or MESBM in the diet decreased the diarrhea index, which could be associated with improved nutrient digestibility and microbial composition.

With the development of pig industry, liquid feeding is becoming more widely used. Therefore, this study explores that liquid-state fermentation through enzymatic hydrolysis and microbial fermentation reduces the level of antigenic protein in soybean meal (SBM). In the present study, dietary supplementation with enzymatically hydrolyzed SBM (ESBM) or microbial fermented and enzymatically hydrolyzed SBM (MESBM) effectively decreased diarrhea index, enhanced nutrient digestibility, and improved the composition and stability of intestinal flora in weaning piglets. Our study not only contributes to the efficient utilization of SBM, but also provides new insights into its application in liquid feeding for livestock farming.

Standardized ileal digestibility of amino acids in soybean meal fed to non-pregnant and pregnant sows.

BACKGROUND: Two studies were designed to determine standard ileal crude protein (CP) and amino acid (AA) digestibility of soybean meal (SBM) from different origins fed to non-pregnant and pregnant sows. Seven solvent-extracted SBMs from soybeans produced in the USA, Brazil, and China were selected. In Exp. 1, eight different diets were created: a nitrogen (N)-free diet and 7 experimental diets containing SBM from different origins as the only N source. Eight non-pregnant, multiparous sows were arranged in an 8 × 8 Latin square design (8 periods and 8 diets). In Exp. 2, the diet formula was the same as in Exp. 1. Eight gestating sows (parity 3) were assigned to 4 different diets in a replicated 4 × 3 Youden square design (three periods and four diets) in mid-gestation and again in late-gestation stages. RESULTS: When fed to non-pregnant and late-gestating sows, the standardized ileal digestibility (SID) of CP and most AAs from different SBM were not significantly different (P > 0.05). When fed to mid-gestating sows, the SID values for Arg, His, Lys, Phe, Cys, Gly, Ser, and Tyr in SBM 1 were lower than in SBM 4 and 5 (P < 0.05), whereas SID for Leu from SBM 5 was higher than in SBM 1 and 4 (P < 0.05). SID values for Ile, Ala, and Asp from SBM 4 were lower than in SBM 1 and 5 (P < 0.05). Sows had significantly greater SID values for Lys, Ala, and Asp during mid-gestation when compared with late-gestation stages (P < 0.05). Mid-gestating sows had greater SID value for Val and lower SID value for Tyr when compared with non-pregnant and late-gestating sows (P < 0.01), whereas non-pregnant sows had significantly greater SID value for Met when compared with gestating sows (P < 0.01). CONCLUSIONS: When fed to mid-gestating sows, the SID values for most AAs varied among SBM samples. The SID values for Lys, Met, Val, Ala, Asp, and Tyr in SBM were affected by sow gestation stages. Our findings provide a cornerstone for accurate SBM use in sow diets.

Selenomethionine alleviates environmental heat stress induced hepatic lipid accumulation and glycogen infiltration of broilers via maintaining mitochondrial and endoplasmic reticulum homeostasis.

With the increasing of global mean surface air temperature, heat stress (HS) induced by extreme high temperature has become a key factor restricting the poultry industry. Liver is the main metabolic organ of broilers, HS induces liver damage and metabolic disorders, which impairs the health of broilers and affects food safety. As an essential trace element for animals, selenium (Se) involves in the formation of antioxidant system, and its biological functions are generally mediated by selenoproteins. However, the mechanism of Se against HS induced liver damage and metabolic disorders in broilers is inadequate. Therefore, we developed the chronic heat stress (CHS) broiler model and investigated the potential protection mechanism of organic Se (selenomethionine, SeMet) on CHS induced liver damage and metabolic disorders. In present study, CHS caused liver oxidative damage, and induced hepatic lipid accumulation and glycogen infiltration of broilers, which are accompanied by mitochondrial dysfunction, abnormal mitochondrial tricarboxylic acid (TCA) cycle and endoplasmic reticulum (ER) stress. Dietary SeMet supplementation increased the hepatic Se concentration and exhibited protective effects via promoting the expression of selenotranscriptome and several key selenoproteins (GPX4, TXNRD2, SELENOK, SELENOM, SELENOS, SELENOT, GPX1, DIO1, SELENOH, SELENOU and SELENOW). These key selenoproteins synergistically improved the antioxidant capacity, and mitigated the mitochondrial dysfunction, abnormal mitochondrial TCA cycle and ER stress, thus recovered the hepatic triglyceride and glycogen concentration. What's more, SeMet supplementation suppressed lipid and glycogen biosynthesis and promoted lipid and glycogen breakdown in liver of broilers exposed to CHS though regulating the AMPK signals. Overall, our present study reveals a potential mechanism that Se alleviates environment HS induced liver damage and glycogen and lipid metabolism disorders in broilers, which provides a preventive and/or treatment measure for environment HS-dependent hepatic metabolic disorders in poultry industry.