Effects of Olive Cake on the Performance, Digestibility, Blood Parameters, and Intestinal Villi of Bísaro Pigs

Olive oil production generates by-products, such as olive cake (OC), which can be used in animal feed, reducing the environmental impact. This study assessed the effects of OC in pig diets on intestinal morphometry and blood parameters. Twenty-four Bísaro pigs were randomly assigned to three treatments: OC0 (control), OC15 (15% dehydrated OC), and OC25 (25% dehydrated OC) for 93 days. The apparent total tract digestibility (ATTD) of dry matter (DM), organic matter (OM), crude protein (CP), crude fat (CF), and fiber (NDF) was evaluated through total feces collection. No significant differences in average daily gain (ADG) or feed conversion ratio (FCR) were found (p > 0.05). However, average daily feed intake (ADFI) increased from 2.84 kg (control) to 3.46 kg (OC15) and 3.64 kg (OC25). OC inclusion increased the ADFI of CF (90.8 g to 171.5 g and 169.2 g) and NDF (586.8 g to 896.6 g and 1115.4 g). The ATTD of all parameters decreased with 25% OC. The digestible intake of DM, OM, and CP was unaffected, but CF intake was higher in OC-fed groups (p = 0.005). Histomorphometric analysis revealed no significant differences in villi size. Lymphocyte counts were higher in OC25 (p < 0.05). This study suggests that up to 15% OC inclusion is feasible without compromising the pigs' performance.

Effects of Fermented Soybean Hulls on Reproductive Performance, Blood Physiology and Immune Parameters Along with Fecal Microbiota in Sows

This study aims to investigate the effects of fermented soybean hulls (FSHS) on reproductive performance, plasma biochemical profiles, immune parameters, and fecal microbiota in sows. A total of 325 sows were randomized into five groups, each fed a diet with varying FSHS proportions: 0% (control), 2% (FSHS2), 4% (FSHS4), 6% (FSHS6), and 8% (FSHS8). Diets were prepared by replacing conventional soybean hulls with FSHS in equal amounts. The study lasted from day 30 to day 110 of gestation. The results indicated the following: (1) Reproductive Performance: The number of live piglets per litter, newborn litter weight, and individual piglet weight increased linearly with the increase in FSHS addition in the diet (PLinear < 0.05). A trend toward reduced farrowing duration was observed when FSHS was added to the diet (PLinear = 0.076). FSHS improved newborn weight and weight variation compared to the control when FSHS was added to the diet (PAnova < 0.05). Replacing soybean hulls with FSHS also increased fecal scores, enhancing fecal consistency and alleviating constipation (p < 0.01). (2) Plasma Biochemical Indicators: Plasma urea concentration on day 60 decreased linearly with increasing FSHS (PLinear < 0.05). Plasma total protein and aspartate aminotransferase (AST) activities showed quadratic effects (PQuadratic < 0.05) on day 60 and 90 of gestation, while alkaline phosphatase activity on day 90 showed a quadratic trend (PQuadratic = 0.082). (3) Hormone Levels: Plasma insulin and adrenaline levels exhibited quadratic effects on day 60 and 90 of gestation, respectively (PQuadratic < 0.05). (4) Immune Parameters: Plasma immunoglobulin G (IgG) and M (IgM) levels increased linearly with FSHS proportion on day 60 (PLinear < 0.05), but no significant changes were observed on day 90 (p > 0.05). (5) Fecal Microbiota: On day 90, the abundance of actinobacteriota increased quadratically with FSHS levels (PQuadratic < 0.05), while bacteroidota decreased linearly (PLinear < 0.05). During parturition, actinobacteriota abundance continued to increase linearly (PLinear < 0.05). Notably, the FSHS8 group had higher actinobacteriota abundance compared to the control group (p = 0.05). At the genus level, terrisporobacter showed a quadratic increase and then decrease (PQuadratic < 0.05), while ruminococcus showed a quadratic decrease and then increased (PQuadratic < 0.05). Both terrisporobacter in the FSHS2 and FSHS6 groups and ruminococcus in the FSHS8 group were more abundant compared to the control (p < 0.01). Conclusions: Dietary supplementation with FSHS increased fecal microbial diversity, alleviated the incidence of constipation, and ultimately improved sow reproductive performance. The recommended optimal addition of FSHS to the sow diet is 6%.

In vitro fermentation characteristics of different types of fiber-rich ingredients by pig fecal inoculum

BACKGROUND

Dietary fibers with varying physicochemical properties have different fermentation characteristics, which may differently impact host health. The present study aimed to determine the fermentation characteristics including gas production kinetics, short-chain fatty acids (SCFAs) production and microbial composition of different fibrous ingredients using in vitro fermentation by fecal microbiota.

RESULTS

Sugar beet pule (SBP), wheat bran (WB), dried corn distillers grains with solubles (DDGS), rice bran (RB) and alfalfa meal (AM) were selected to fermentation in vitro for 36 h. The results showed that SBP had the greatest gas production. SBP had the highest in vitro dry matter fermentability (IVDMF) and production of acetate, propionate and total SCFAs, followed by WB, which were all greater than DDGS, AM and RB. The alpha-diversity was higher in the DDGS, AM and RB groups than in the WB and SBP groups. Differences in microbial community composition were observed among groups. The relative abundance of Treponema was highest in WB group. RB group showed lower Prevotella abundance than other groups but had higher Succinivibrio abundance. Interestingly, the Lactobacillus reached the highest abundances in the DDGS group. Correlation analysis indicated that the relative abundance of Treponema and Prevotella was positively associated with the gas production, IVDMF and SCFAs, whereas norank_f_Muribaculaceae, Rikenellaceae_RC9_gut_group, Lysinibacillus and Succinivibrio were the opposite.

CONCLUSION

Collectively, WB and SBP were fermented rapidly by fecal microbiota compared to DDGS, AM and RB. Different fiber sources have different fiber compositions and fermentation properties that affect the microbial compositins and SCFAs production. © 2024 Society of Chemical Industry.

Modulation of pectin on intestinal barrier function via changes in microbial functional potential and bile acid metabolism

Weaning is one of the major factors that cause stress and intestinal infection in infants and in young animals due to an immature intestine and not fully developed immune functions. Pectin (PEC), a prebiotic polysaccharide, has attracted considerable attention in intestinal epithelial signaling and function via modulation of the microbial community. A total of 16 weaned piglets (21-d-old) were randomly assigned into two groups: control group and PEC group. Supplementation of 5% pectin improved intestinal mucosal barrier function by modulating the composition of the bile acid pool in piglets. Specifically, piglets in PEC group had less serum D-lactate content and alkaline phosphatase activity. In the ileum, dietary pectin increased the number of crypt PAS/AB-positive goblet cells and the mRNA expressions of MUC2, ZO-1, and Occludin. Piglets in PEC group displayed a decreased abundance of Enterococcus (2.71 vs. 65.92%), but the abundances of Lactobacillus (30.80 vs. 7.93%), Streptococcus (21.41 vs. 14.81%), and Clostridium_sensu_stricto_1 (28.34 vs. 0.01%) were increased. Elevated concentrations of bile acids especially hyocholic acid species (HCAs) including HCA, HDCA, and THDCA were also observed. Besides, correlation analysis revealed that dietary pectin supplementation may have beneficial effects through stimulation of the crosstalk between gut microbes and bile acid synthesis within the enterohepatic circulation. Thus, dietary pectin supplementation exhibited a further positive effect on the healthy growth and development of weaned piglets. These findings suggest pectin supplementation as the prebiotic is beneficial for gut health and improvement of weaned stress via regulating microbiota and bile acid metabolism.

Effects of Different Types of Dietary Fibers on Lipid Metabolism and Bile Acids in Weaned Piglets

The aim of this study was to investigate the effects of dietary fiber on the serum biochemistry, bile acid profile, and gut microbiota in piglets. Twenty-four pigs (initial body weight: 10.53 ± 1.23 kg) were randomly divided into three treatments with eight replicate pens of one pig per pen for 21 d. The dietary treatments consisted of the following: (1) a fiber-free diet (NS); (2) a fiber-free diet + 3% fructooligosaccharides (SI); (3) a fiber-free diet + 3% dietary fiber mixture (fructooligosaccharides, long-chain inulin, and microcrystalline cellulose at the ratio 1:1:1; MIX). The results showed that compared with the NS group, the 3% SI diet reduced the serum total cholesterol (TC) concentration of the piglets (p < 0.05). The metabolomics results showed that the 3% SI diet increased the level of taurohyocholic acid (THCA) and α-muricholic acid, and the 3% MIX diet increased the level of THCA and cholic acid (p < 0.05). The use of 3% SI or MIX decreased the glycodeoxycholic acid (GDCA) level in the bile of the piglets (p < 0.05). The correlation analysis shows that the GDCA was positively related to the TC. The 16S rRNA gene sequencing results showed that UCG-002 and Holdemanella were enriched in the SI group, while Bacteroides was enriched in the MIX group. The microbial function prediction indicated that SI supplementation tended to elevate the relative abundance of gut bacteria capable of expressing bile acid-metabolizing enzymes. To sum up, the regulatory effect of dietary fiber on lipid metabolism is related to bile acids in piglets. Compared with MIX, SI is more likely to regulate bile acids through the gut microbiota.

The impact of common pharmaceutical excipients on the gut microbiota

INTRODUCTION

Increasing attention is being afforded to understanding the bidirectional relationships that exist between oral medications and the gut microbiota, in an attempt to optimize pharmacokinetic performance and mitigate unwanted side effects. While a wealth of research has investigated the direct impact of active pharmaceutical ingredients (APIs) on the gut microbiota, the interactions between inactive pharmaceutical ingredients (i.e. excipients) and the gut microbiota are commonly overlooked, despite excipients typically representing over 90% of the final dosage form.

AREAS COVERED

Known excipient-gut microbiota interactions for various classes of inactive pharmaceutical ingredients, including solubilizing agents, binders, fillers, sweeteners, and color additives, are reviewed in detail.

EXPERT OPINION

Clear evidence indicates that orally administered pharmaceutical excipients directly interact with gut microbes and can either positively or negatively impact gut microbiota diversity and composition. However, these relationships and mechanisms are commonly overlooked during drug formulation, despite the potential for excipient-microbiota interactions to alter drug pharmacokinetics and interfere with host metabolic health. The insights derived from this review will inform pharmaceutical scientists with the necessary design considerations for mitigating potential adverse pharmacomicrobiomic interactions when formulating oral dosage forms, ultimately providing clear avenues for improving therapeutic safety and efficacy.

Metabolomic Characteristics of Cecum Contents in High-Fat-Diet-Induced Obese Mice Intervened with Different Fibers

The aim of this study was to demonstrate the effect of single or mixed fibers (arabinoxylan, β-glucan, xyloglucan, and inulin) on the metabolome of cecum content in mice with obesity caused by a high-fat diet. Twenty-eight six-week-old male mice were divided randomly into seven groups (n = 4/group), including a normal-diet group (CON), a high-fat-diet group (HFD), and groups with the same high-fat diet but supplemented with arabinoxylan (HFAX), arabinoxylan + β-glucan (HFAβ), arabinoxylan + xyloglucan (HFAG), xyloglucan (HFXG), and xyloglucan + inulin (HFXI). A total of 66 molecules were identified and quantified in cecum content by proton nuclear magnetic resonance (1 H-NMR). The metabolomic profiles combined with statistical analysis revealed compounds distinguishing the control group from those supplemented with fibers. In detail, a high-fat diet could significantly elevate the concentrations of acetone and methionine (p < 0.05) while decreasing the levels of methanol, arabinose, acetate, and 3-hydroxyphenylacetate (p < 0.05) in the cecum contents of mice. Compared to HFD, the supplementation caused higher levels of fumarate and hypoxanthine (p < 0.05) and lower levels of phenylacetate, acetate, fucose, formate, proline, betaine, and trimethylamine N-oxide (TMAO) (p < 0.05). An enrichment analysis highlighted that the pathways mainly altered were amino sugar metabolism, aspartate metabolism, and arginine and proline metabolism. In conclusion, non-starch polysaccharide (NSP) supplementation could change the metabolomic profiles of cecum contents in obese mice as a result of a high-fat diet. Moreover, mixed NSPs exhibited more beneficial effects than singular form on gut metabolism.

Time-course effects of different fiber-rich ingredients on energy values, microbiota composition and SCFA profile in growing pigs

This study was to investigate time-course effects of different types of dietary fiber on the energy values, fecal microbiota and short-chain fatty acid (SCFA) concentration in growing pigs. A total of 24 barrows (initial body weight, 19.8 ± 0.5 kg) were assigned to 4 dietary treatments based on body weight (BW) in a completely randomized design, including a basal diet (CON) and 3 fiber-rich diets replacing corn, soybean meal and soybean oil in the CON diet with 20% sugar beet pulp (SBP), defatted rice bran (DFRB) or soybean hull (SBH), respectively. Fresh feces were sampled on d 7, 14 and 21, followed by 5 d total feces and urine collections. The results showed that there were no differences in DE and ME between any of the fiber ingredients on d 7, 14 or 21. However, fiber inclusion decreased the DE and ME of the diet (P < 0.05) regardless of the time effect. Principal coordinate analysis (PCoA) revealed distinctly different microbial communities on the DFRB diet and SBH diet across different times (P < 0.05) and the fecal microbiota of the 4 diet groups demonstrated notably distinct clusters at each time point (P < 0.05). With adaptation time increased from 7 to 21 d, cellulose-degrading bacteria and SCFA-producing bacteria (e.g., Ruminococcaceae _UCG-014, Rikenellaceae _RC9_gut_group and Bifidobacterium) increased in the fiber inclusion diets, and pathogenic genera (e.g., Streptococcus and Selenomonas) were increased in the basal diet (P < 0.05). Furthermore, the gut microbiota of growing pigs adapted more easily and quickly to the SBP diet compared to the DFRB diet, as reflected by the concentration of propionate, butyrate, isovalerate and total SCFA which increased with time for growing pigs fed the DFRB diet (P < 0.05). Collectively, our results indicated at least 7 d adaptation was required to evaluate the energy values of fiber-rich ingredients, as the hindgut microbiota of growing pigs may need more time to adapt to a high fiber diet, especially for insoluble dietary fiber.

Effects of high-altitude hypoxic environment on colonic inflammation, intestinal barrier and gut microbiota in three-way crossbred commercial pigs

In recent years, the three-way crossbred commercial pigs are extensively cultured in Tibet. However, there have been few studies about the effect of high-altitude hypoxic environment on intestinal health of them. Therefore, we selected Tibetan pigs (TP) and the three-way crossbred commercial pigs (CP-H) living in the Tibet (3,500–3,700 m in altitude) as a positive control group and treatment group, respectively. The three-way crossbred commercial pigs (CP-L) living at altitudes 800–1,000 m sea level were selected as a negative control group. The colonic chyme, colonic mucosa, colonic tissue and serum samples were collected for the detection of gut microbiota and intestinal inflammation. The results showed that high-altitude hypoxic environment promoted the occurrence of colonic inflammation, disrupted the colonic barrier to some extent. And Hematoxylin–Eosin (HE) staining revealed that mild inflammatory cell infiltration was observed in colon of CP-H. 16S rRNA gene sequencing revealed that the microbial community composition of CP-H was changed compared with CP-L. Gut bacterial communities formed distinctly different clusters in principal coordinates analysis (PCoA) space, and Chao 1 index of CP-H was also decreased. At the genus level, Terrisporobacter showed greater enrichment in the CP-H than lower-altitude pigs. Colstridium-sensu-stricto-1 showed lower enrichment in the CP-H than lower-altitude pigs. However, the concentration of valeric acid in colonic chyme of CP-H was higher than CP-L and TP. Correlation analysis indicated that Terrisporobacter was positively associated with the relative mRNA expression level of IL-1β and the content of lipopolysaccharide (LPS), and was negatively correlated with the relative mRNA expression level of IL-10. The Streptococcus was positively associated with the concentrations of valerate. In summary, high-altitude hypoxic environment changed compositions of gut microbiota, promoted the occurrence of colonic inflammation, and disrupted intestinal barrier of the three-way crossbred commercial pigs.

Pectin supplementation ameliorates intestinal epithelial barrier function damage by modulating intestinal microbiota in lipopolysaccharide-challenged piglets

During weaning, infants and young animals are susceptible to severe enteric infections, thus inducing intestinal microbiota dysbiosis, intestinal inflammation, and impaired intestinal barrier function. Pectin (PEC), a prebiotic polysaccharide, enhances intestinal health with the potential for therapeutic effect on intestinal diseases. One 21-days study was conducted to investigate the protective effect of pectin against intestinal injury induced by intraperitoneal injection of Escherichia coli lipopolysaccharide (LPS) in a piglet model. A total of 24 piglets (6.77±0.92 kg BW; Duroc × Landrace × Large White; barrows; 21 d of age) were randomly assigned into three groups: control group, LPS-challenged group, and PEC + LPS group. Piglets were administrated with LPS or saline on d14 and d21 of the experiment. All piglets were slaughtered and intestinal samples were collected after 3 h administration on d21. Pectin supplementation ameliorated the LPS-induced inflammation response and damage to the ileal morphology. Meanwhile, pectin also improved intestinal mucin barrier function, increased the mRNA expression of MUC2, and improved intestinal mucus glycosylation. LPS challenge reduced the diversity of intestinal microbiota and enriched the relative abundance of Helicobacter. Pectin restored alpha diversity improved the structure of the gut microbiota by enriching anti-inflammatory bacteria and short-chain fatty acid (SCFA)-producing bacteria, and increased the concentrations of acetate. In addition, Spearman rank correlation analysis also revealed the potential relationship between intestinal microbiota and intestinal morphology, intestinal inflammation, and intestinal glycosylation in piglets. Taken together, these results indicate that pectin enhances intestinal integrity and barrier function by altering intestinal microbiota composition and their metabolites, which subsequently alleviates intestinal injury and finally improves the growth performance of piglets.

Baicalin Alleviates Short-Term Lincomycin-Induced Intestinal and Liver Injury and Inflammation in Infant Mice

The adverse effects of short-term megadose of antibiotics exposure on the gastrointestinal and liver tissue reactions in young children have been reported. Antibiotic-induced intestinal and liver reactions are usually unpredictable and present a poorly understood pathogenesis. It is, therefore, necessary to develop strategies for reducing the adverse effects of antibiotics. Studies on the harm and rescue measures of antibiotics from the perspective of the gut–liver system are lacking. Here, we demonstrate that lincomycin exposure reduced body weight, disrupted the composition of gut microbiota and intestinal morphology, triggered immune-mediated injury and inflammation, caused liver dysfunction, and affected lipid metabolism. However, baicalin administration attenuated the lincomycin-induced changes. Transcriptome analysis showed that baicalin improved immunity in mice, as evidenced by the decreased levels of intestinal inflammatory cytokines and expression of genes that regulate Th1, Th2, and Th17 cell differentiation, and inhibited mucin type O-glycan biosynthesis pathways. In addition, baicalin improved liver function by upregulating the expression of genes involved in bile acid secretion and lipid degradation, and downregulating genes involved in lipid synthesis in lincomycin-treated mice. Bile acids can regulate intestinal immunity and strengthen hepatoenteric circulation. In addition, baicalin also improved anti-inflammatory bacteria abundance (Blautia and Coprobacillus) and reduced pathogenic bacteria abundance (Proteobacteria, Klebsiella, and Citrobacter) in lincomycin-treated mice. Thus, baicalin can ameliorate antibiotic-induced injury and its associated complications such as liver disease.

Heat stress-induced mucosal barrier dysfunction is potentially associated with gut microbiota dysbiosis in pigs

Heat stress (HS) can be detrimental to the gut health of swine. Many negative outcomes induced by HS are increasingly recognized as including modulation of intestinal microbiota. In turn, the intestinal microbiota is a unique ecosystem playing a critical role in mediating the host stress response. Therefore, we aimed to characterize gut microbiota of pigs’ exposure to short-term HS, to explore a possible link between the intestinal microbiota and HS-related changes, including serum cytokines, oxidation status, and intestinal epithelial barrier function. Our findings showed that HS led to intestinal morphological and integrity changes (villus height, serum diamine oxidase [DAO], serum D-lactate and the relative expressions of tight junction proteins), reduction of serum cytokines (interleukin [IL]-8, IL-12, interferon-gamma [IFN-γ]), and antioxidant activity (higher glutathione [GSH] and malondialdehyde [MDA] content, and lower superoxide dismutase [SOD]). Also, 16S rRNA sequencing analysis revealed that although there was no difference in microbial α-diversity, some HS-associated composition differences were revealed in the ileum and cecum, which partly led to an imbalance in the production of short-chain fatty acids including propionate acid and valerate acid. Relevance networks revealed that HS-derived changes in bacterial genera and microbial metabolites, such as Chlamydia, Lactobacillus, Succinivibrio, Bifidobacterium, Lachnoclostridium, and propionic acid, were correlated with oxidative stress, intestinal barrier dysfunction, and inflammation in pigs. Collectively, our observations suggest that intestinal damage induced by HS is probably partly related to the gut microbiota dysbiosis, though the underlying mechanism remains to be fully elucidated.

Early-Life Nutrition Interventions Improved Growth Performance and Intestinal Health via the Gut Microbiota in Piglets

Intestinal infections in piglets are the main causes of morbidity before and after weaning. Studies have not explored approaches for combining pre-weaning and post-weaning nutritional strategies to sustain optimal gut health. The current study thus sought to explore the effects of early-life nutrition interventions through administration of synthetic milk on growth performance and gut health in piglets from 3 to 30 days of age. Twelve sows were randomly allocated to control group (CON) and early-life nutrition interventions group (ENI). Piglets were fed with the same creep diet from 7 days of age ad libitum. Piglets in the ENI group were provided with additional synthetic milk from Day 3 to Day 30. The results showed that early-life nutrition interventions improved growth performance, liver weight, spleen weight, and reduced diarrhea rate of piglets after weaning (P < 0.05). Early-life nutrition interventions significantly upregulated expression of ZO-1, Occludin, Claudin4, GALNT1, B3GNT6, and MUC2 in colonic mucosa at mRNA level (P < 0.05). Early-life nutrition interventions reduced activity of alkaline phosphatase (AKP) in serum and the content of lipopolysaccharides (LPS) in plasma (P < 0.05). The number of goblet cells and crypt depth of colon of piglets was significantly higher in piglets in the ENI group relative to that of piglets in the CON group (P < 0.05). The relative mRNA expression levels of MCP-1, TNF-α, IL-1β, and IL-8, and the protein expression levels of TNF-α, IL-6, and IL-8 in colonic mucosa of piglets in the ENI group were lower compared with those of piglets in the CON group (P < 0.05). Relative abundance of Lactobacillus in colonic chyme and mucosa of piglets in the ENI group was significantly higher relative to that of piglets in the CON group (P < 0.05). Correlation analysis indicated that abundance of Lactobacillus was positively correlated with the relative mRNA expression levels of ZO-1, Claudin4, and GALNT1, and it was negatively correlated with the level of MCP-1 in colonic chyme and mucosa. In summary, the findings of this study showed that early-life nutrition interventions improved growth performance, colonic barrier, and reduced inflammation in the colon by modulating composition of gut microbiota in piglets. Early-life nutrition intervention through supplemental synthetic milk is a feasible measure to improve the health and reduce the number of deaths of piglets.

Supplementing Glycerol to Inoculum Induces Changes in pH, SCFA Profiles, and Microbiota Composition in In-Vitro Batch Fermentation

Glycerol was generally added to the inoculum as a cryoprotectant. However, it was also a suitable substrate for microbial fermentation, which may produce more SCFAs, thereby decreased pH of the fermentation broth. This study investigated the effect of supplementing glycerol to inoculum on in vitro fermentation and whether an enhanced buffer capacity of medium could maintain the pH stability during in vitro batch fermentation, subsequently improving the accuracy of short chain fatty acids (SCFAs) determination, especially propionate. Two ileal digesta were fermented by pig fecal inoculum with or without glycerol (served as anti-frozen inoculum or frozen inoculum) in standard buffer or enhanced buffer solution (served as normal or modified medium). Along with the fermentation, adding glycerol decreased the pH of fermentation broth (p < 0.05). However, modified medium could alleviate the pH decrement compared with normal medium (p < 0.05). The concentration of total propionic acid production was much higher than that of other SCFAs in anti-frozen inoculum fermentation at 24 and 36 h, thereby increasing the variation (SD) of net production of propionate. The α-diversity analysis showed that adding glycerol decreased Chao1 and Shannon index under normal medium fermentation (p < 0.05) compared to modified medium (p < 0.05) along with fermentation. PCoA showed that all groups were clustered differently (p < 0.01). Adding glycerol improved the relative abundances of Firmicutes, Anaerovibrio, unclassified_f_Selenomonadaceae, and decreased the relative abundance of Proteobacteria (p < 0.05). The relative abundances of Firmicutes, such as Lactobacillus, Blautia and Eubacterium_Ruminantium_group in modified medium with frozen inoculum fermentation were higher than (p < 0.05) those in normal medium at 36 h of incubation. These results showed that adding glycerol in inoculum changed the fermentation patterns, regardless of substrate and medium, and suggested fermentation using frozen inoculum with modified medium could maintain stability of pH, improve the accuracy of SCFA determination, as well as maintain a balanced microbial community.

Gut microbiota mediates the effects of inulin on enhancing sulfomucin production and mucosal barrier function in a pig model

Dietary fibers (DFs) have many beneficial effects on intestinal health by ameliorating intestinal inflammation and modulating the microbial community composition, thereby affecting the barrier function. This study aims to characterize the gut microbiota of pigs fed with DFs, revealing a link between the intestinal microbiota and mucin chemotypes. Pigs (six per group) were randomly allotted to consume one of the following diets: control (CON) or a diet supplemented with 5% microcrystalline cellulose (MCC) or inulin (INU) for 72 days. We found that INU but not MCC enhanced the colonic barrier function by promoting the expression of ZO-1, Occludin and MUC2 and reducing the colonic crypt depth. INU increased sulfomucin production and mRNA levels of sulfotransferases Gal3ST1 and Gal3ST2. Goblet cells in the ileum were found to contain predominantly sialomucins while colonic goblet cells were dominated by sulfomucins with sialomucins absent. DF consumption increased the concentrations of short-chain fatty acids (SCFAs) of the ileum and colon compared to the CON diet. Moreover, the results of 16S rRNA gene sequencing analysis revealed that DFs significantly altered the composition of ileal and colonic mucosal microbiota. Network analysis indicated that INU-induced changes in bacterial genera and SCFAs, such as Akkermansia and butyrate, were significantly related with sulfomucins and the mucosal barrier function-gene in pigs. Collectively, these findings suggest that the intestinal mucosal microbiota and SCFAs induced by INU play a crucial role in modulating the chemotypes of mucin and the barrier function.

Effects of Multi-Bacteria Solid-State Fermented Diets with Different Crude Fiber Levels on Growth Performance, Nutrient Digestibility, and Microbial Flora of Finishing Pigs

Simple Summary

Dietary cellulase was found to be an important nutrient, and solid-state fermentation could improve the nutritional value of feed. To study the effects of multi-bacteria solid-state fermented diets and dietary crude fiber levels on finishing pigs, a total of 36 pigs were divided into four treatments: (1) pigs fed a basal diet containing 7.00% CF (HF), (2) pigs fed a basal multi-bacteria fermentation diet containing 7.00% CF (HFM), (3) pigs fed a basal diet containing 2.52% CF (LF), and (4) piglets fed a basal multi-bacteria fermentation diet containing 2.52% CF (LFM). The growth performance, nutrient digestibility and digestion amount, serum biochemical index, and fecal microflora were evaluated. Multi-bacteria solid-state fermentation had a positive effect on the nutrient digestion and serum biochemical indicators, which was contrary to high-fiber diets. Both high-fiber diets and multi-bacteria solid-state fermentation could optimize intestinal flora in finishing pigs.

Abstract

This study aimed to investigate the effects of multi-bacteria solid-state fermented diets with different crude fiber (CF) levels on growth performance, nutrient digestibility, and microbial flora of finishing pigs. The multi-bacteria solid-state fermented diets were made up of Lactobacillus amylovorus, Enterococcus faecalis, Bacillus subtilis, and Candida utilis. According to a 2 (factors) × 2 (levels) design, with the two factors being multi-bacteria solid-state fermentation (fed non-fermented diet or multi-bacteria fermentation) or CF levels (fed a basal diet containing 2.52% CF or 7.00% CF), a total of 36 finishing pigs (70.80 ± 5.75 kg) were divided into 4 treatments with 9 barrows per group: (1) pigs fed a diet containing 7.00% CF (HF), (2) pigs fed a multi-bacteria fermentation diet containing 7.00% CF (HFM), (3) pigs fed a diet containing 2.52% CF (LF), and (4) piglets fed a multi-bacteria fermentation diet containing 2.52% CF (LFM). This experiment lasted 28 days. The multi-bacteria solid-state fermented diet increased the backfat thickness (p < 0.05) and apparent total tract nutrient digestibility (ATTD) of CF, neutral detergent fiber (NDF), acid detergent fiber (ADF), crude protein (CP), 8 amino acids (Trp, Asp, Gly, Cys, Val, Met, Ile, and Leu), total essential amino acids (EAA), total non-essential amino acids (NEEA), and total amino acids (TAA) (p < 0.05). Multi-bacteria solid-state fermented diet increased serum concentrations of HDL-c, ABL, TP, and GLU, the serum enzyme activities of GSH-Px, T-AOC, SOD, and CAT (p < 0.05), the relative abundance of Lactobacillus, Oscillospira, and Coprococcus (p < 0.05), and the abundance of YAMINSYN3-PWY, PWY-7013, GOLPDLCAT-PWY, ARGORNPROST-PWY, and PWY-5022 pathways (p < 0.05). The multi-bacteria solid-state fermented diet reduced the digestion amount of CF, NDF, and ADF (p < 0.05), the serum concentrations of TC, TG, LDL-c, BUN, and MDA (p < 0.05), the relative abundance of Streptococcaceae (p < 0.05), and the abundance of PWY-6470, PWY0-862, HSERMETANA-PWY, LACTOSECAT-PWY, MET-SAM-PWY, PWY-6700, PWY-5347, PWY0-1061, and LACTOSECAT-PWY pathways (p < 0.05). The high-fiber diet increased average daily feed intake (p < 0.05), the serum concentrations of TC, TG, LDL-c, BUN, and MDA (p < 0.05), the relative abundance of Clostridiaceae_Clostridium and Coprococcus (p < 0.05), and the abundance of TCA-GLYOX-BYPASS, GLYCOLYSIS-TCA-GLYOX-BYPASS, and PWY-6906 pathways (p < 0.05). The high-fiber diet reduced chest circumference (p < 0.05) and ATTD of ether extract (EE), CF, NDF, ADF, Ca, CP, 18 amino acids (Trp, Thr, Val, Met, Ile, Leu, Phe, Lys, His, Arg Asp, Ser, Glu, Gly, Ala, Cys, Tyr, and Pro), EAA, NEAA, and TAA (p < 0.05). The high-fiber diet also reduced the serum concentrations of HDL-c, TP, ABL, and GLU, the serum enzyme activities of T-AOC, GSH-Px, SOD, and CAT (p < 0.05), and the relative abundance of Akkermansia and Oscillospira (p < 0.05). There was no significant effect of the interaction between multi-bacteria fermentation and dietary CF levels, except on the digestion amount of CF (p < 0.05). The 7.00% CF had a negative effect on the digestion of nutrients, but multi-bacteria solid-state fermentation diets could relieve this negative effect and increase backfat thickness. High-fiber diets and multi-bacteria solid-state fermentation improved the diversity and abundance of fecal microorganisms in finishing pigs.

Dietary inulin supplementation modulates the composition and activities of carbohydrate-metabolizing organisms in the cecal microbiota of broiler chickens

Inulin is a highly effective prebiotic and an attractive alternative to antibiotic growth promoters for increasing production and maintaining health in chickens. However, how inulin elicits its effects on members of the intestinal microbiota is unknown, even though their importance for energy metabolism and the health of chickens is well documented. A combination of 16S rRNA Illumina sequencing and transcriptomic analysis was used to investigate the effects of supplementing a corn-based basal diet with 1, 2, or 4% inulin or 400 ppm bacitracin on the composition, diversity and activities of carbohydrate-metabolizing organisms (CMOs) in the cecal microbiota of broiler chickens. We found that members of Bacteroides were the most abundant non-starch degrading CMOs, contributing 43.6–52.1% of total glycoside hydrolase genes and 34.6–47.1% activity to the meta-transcriptomes of chickens in the different dietary groups, although members of Parabacteroides, Prevotella, Alistipes, Clostridium, Barnesiella, Blastocystis, Faecalibacterium and others were also actively involved. Inulin and bacitracin inclusion in the basal diet did not change significantly the composition or diversity of these CMOs. Inulin supplementation at three levels promoted the activities of Bacteroides, Prevotella and Bifidobacterium, and 2% level appears to be the most optimal dosage for bifidobacterial activity.

Dietary Inulin Regulated Gut Microbiota and Improved Neonatal Health in a Pregnant Sow Model

This study aimed to investigate the relationship between maternal dietary fiber intake and piglet health. Multiparous sows were randomly assigned to two groups and fed diets without inulin (control group, n = 20) or 1.6% inulin (1.6IN group, n = 20). The results indicate that 1.6IN prevented the prolonged farrowing duration of sows (P < 0.05) and shortened the average piglet birth interval (P < 0.1). In addition, 1.6IN decreased the percentage of the piglet born weak and the percentage of the piglet with hyperthermia after birth (P < 0.01). Compared with the control group, the 1.6IN group had a lower concentration of urea nitrogen in the colostrum, and also prevented diarrhea, increased litter gain, survival rate, and average daily gain for suckling piglets (P < 0.05). Furthermore, 1.6IN decreased the relative abundance of Firmicutes, Cyanobacteria, and Streptococcus; increased the relative abundance of Bacteroidetes, Desulfovibrio, Paludibacter, CF231, and Prevotella. Overall, this study showed that maternal fiber nutrition during pregnancy regulated the health of offspring, and the response of the maternal intestinal microbes played an important role in intervening in the phenotype of sows and neonatal piglets.

Short-Term Lincomycin Exposure Depletion of Murine Microbiota Affects Short-Chain Fatty Acids and Intestinal Morphology and Immunity

Lincomycin, as one of the most commonly used antibiotics, may cause intestinal injury, enteritis and other side effects, but it remains unknown whether these effects are associated with microbial changes and the effects of different doses of lincomycin on infants. Here, 21-day old mice were exposed to 1 and 5 g/L lincomycin to explore the effects of lincomycin on the gut microbiota, metabolites and inflammation. Compared to the control mice, 1 g/L lincomycin exposure decreased the body weight gain of mice (p < 0.05). Both 1 and 5 g/L lincomycin exposure reduced the diversity and microbial composition of mice (p < 0.05). Furthermore, 1 and 5 g/L lincomycin reduced the relative concentrations of acetate, propionate, butyrate, valerate, isobutyric acid and isovaleric acid in the colon chyme of mice (p < 0.05). In addition, 5 g/L lincomycin exposure reduced the villus height, crypt depth, and relative expression of TLR2, TLR3, TLR4, IL-18, TNF-α, and p65 in the jejunum of mice (p < 0.05), while 1 g/L lincomycin exposure reduced the relative expression of TLR2, TLR3, TNF-α, and p65 (p < 0.05). Collectively, these results highlight the depletion effect of short-term lincomycin exposure on microbiota and the further regulatory effect on intestinal morphology and immunosuppression in infant mice.

Modulation of Pectin on Mucosal Innate Immune Function in Pigs Mediated by Gut Microbiota

The use of prebiotics to regulate gut microbiota is a promising strategy to improve gut health. Pectin (PEC) is a prebiotic carbohydrate that enhances the health of the gut by promoting the growth of beneficial microbes. These microbes produce metabolites that are known to improve mucosal immune responses. This study was conducted to better understand effects of PEC on the microbiome and mucosal immunity in pigs. Pigs were fed two diets, with or without 5% apple PEC, for 72 days. Effects of PEC on the microbiota, cytokine expression, short-chain fatty acids (SCFAs) concentration and barrier function were examined in the ileum and cecum of the pigs. An integrative analysis was used to determine interactions of PEC consumption with bacterial metabolites and microbiome composition and host mucosal responses. Consumption of PEC reduced expression of pro-inflammatory cytokines such as IFN-γ, IL-6, IL-8, IL-12 and IL-18, and the activation of the pro-inflammatory NF-κB signaling cascade. Expression of MUC2 and TFF and the sIgA content was upregulated in the mucosa of PEC-fed pigs. Network analysis revealed that PEC induced significant interactions between microbiome composition in the ileum and cecum on mucosal immune pathways. PEC-induced changes in bacterial genera and fermentation metabolites, such as Akkermansia, Faecalibacterium, Oscillibacter, Lawsonia and butyrate, correlated with the differentially expressed genes and cytokines in the mucosa. In summary, the results demonstrate the anti-inflammatory properties of PEC on mucosal immune status in the ileum and cecum effected through modulation of the host microbiome.

Astaxanthin (ATX) enhances the intestinal mucosal functions in immunodeficient mice

Increasing pressure of life may bring some disease risks and stress injuries, which may destroy the immune system and result in intestinal mucosal immune disorders. In this study, the effects of different doses of ATX (30 mg per kg b.w., 60 mg per kg b.w. and 120 mg per kg b.w.) on intestinal mucosal functions were explored in cyclophosphamide (Cy)-induced immunodeficient mice. The results showed that continuous intraperitoneal injection of 100 mg per kg b.w. Cy for three days led to a persistent decrease of body weight and a range of abnormalities in the intestine of C57BL/6 mice. However, administration of ATX at 60 and 120 mg per kg b.w. could effectively prevent intestinal mucosa from this damage, including reduced levels of oxidative stress (MDA, GSH and GSH-PX), increased intestinal morphological structural integrity, stimulative growth of goblet cells and mucous secretion, decreased development of Paneth cells and expression levels of antimicrobial peptides (AMPs) (Reg-3γ and lysozyme), increased IgA secretion, ameliorative main gut flora (especially total bacteria, Lactobacillus and Enterobacteriaceae spp. ) and its metabolites (acetic acid, propionic acid and butyric acid). These protective effects of ATX were better than those of control-β-carotene in general. Our results may provide a new protective measure to keep intestinal mucosal barriers, which is of great significance for maintaining immune function in the body.

Effects of Collection Durations on the Determination of Energy Values and Nutrient Digestibility of High-Fiber Diets in Growing Pigs by Total Fecal Collection Method

Simple Summary

The total fecal collection method is the gold standard to estimate the energy values and nutrient digestibility of the swine diet. However, there is no standard collection duration for animals that should be sampled in swine research using the total fecal collection method. Thus, this study aimed to investigate the effects of different collection durations (3-day, 5-day, or 7-day) on energy values and nutrient digestibility of high-fiber diets in growing pigs by time-based total fecal collection method. The results showed that the digestible energy (DE), metabolizable energy (ME), and apparent total tract digestibility (ATTD) of gross energy (GE) and most nutrients in diets decreased linearly as the collection duration increased from a 3-day to a 7-day collection. However, there were no differences in the ATTD of GE and nutrient between the 5-day and 7-day collection durations. In addition, the energy values and the ATTD of GE and nutrient of high-fiber ingredients (sugar beet pulp (SBP) or defatted rice bran (DFRB)) were also not affected by the collection durations. Therefore, the results of this research suggest that a 5-day collection duration is adequate to determine the energy values and the ATTD of nutrient in diets containing high-fiber ingredients for growing pigs by time-based total fecal collection method.

Abstract

This study was conducted to evaluate the effect of collection durations on the energy values and nutrient digestibility of high-fiber diets in growing pigs with a time-based total fecal collection method. A total of 24 barrows (body weight (BW): 31.1 ± 1.5 kg) were allotted to a completely randomized design with three diets. Diets included a corn–soybean meal (CSM) basal diet and two additional diets containing 20% sugar beet pulp (SBP) or defatted rice bran (DFRB) by replacing corn, soybean meal, and soybean oil in the CSM diet, respectively. Each diet was fed to eight barrows for a 7-day adaptation period followed by a 7-day total feces and urine collection period. The 7-day collection duration was divided into three collection phases, namely, phase 1 (days 8 to 11), phase 2 (days 11 to 13), and phase 3 (days 13 to 15). Then, similar portions of feces and urine from the different collection phases were composited into three additional samples (days 8 to 11, days 8 to 13, and days 8 to 15, respectively). The results showed that the digestible energy (DE), metabolizable energy (ME), and apparent total tract digestibility (ATTD) of gross energy (GE) and nutrient in experimental diets decreased linearly as the collection durations increased from a 3-day to a 7-day collection (p < 0.05). However, there were no differences in the energy values, GE, and nutrient digestibility of diets and of high-fiber ingredients between the 5-day and 7-day collection durations. In conclusion, this study suggests that a 5-day collection duration is adequate to determine the energy values and nutrient digestibility of high-fiber diets containing SBP or DFRB in growing pigs by the time-based total fecal collection method.

Bioregional Alterations in Gut Microbiome Contribute to the Plasma Metabolomic Changes in Pigs Fed with Inulin

Inulin (INU) is a non-digestible carbohydrate, known for its beneficial properties in metabolic disorders. However, whether and how gut microbiota in its regulation contributes to host metabolism has yet to be investigated. We conduct this study to examine the possible associations between the gut microbiota and circulating gut microbiota-host co-metabolites induced by inulin interventions. Plasma and intestinal site samples were collected from the pigs that have consumed inulin diet for 60 days. High-throughput sequencing was adopted for microbial composition, and the GC-TOF-MS-based metabolomics were used to characterize featured plasma metabolites upon inulin intervention. Integrated multi-omics analyses were carried out to establish microbiota-host interaction. Inulin consumption decreased the total cholesterol (p = 0.04) and glucose (p = 0.03) level in serum. Greater β-diversity was observed in the cecum and colon of inulin-fed versus that of control-fed pigs (p < 0.05). No differences were observed in the ileum. In the cecum, 18 genera were altered by inulin, followed by 17 in the colon and 6 in the ileum. Inulin increased propionate, and isobutyrate concentrations but decreased the ratio of acetate to propionate in the cecum, and increased total short fatty acids, valerate, and isobutyrate concentrations in the colon. Metabolomic analysis reveals that indole-3-propionic acid (IPA) was significantly higher, and the branched-chain amino acids (BCAA), L-valine, L-isoleucine, and L-leucine are significantly lower in the inulin groups. Mantel test and integrative analysis revealed associations between plasma metabolites (e.g., IPA, BCAA, L-tryptophan) and inulin-responsive cecal microbial genera. These results indicate that the inulin has regional effects on the intestine microbiome in pigs, with the most pronounced effects occurring in the cecum. Moreover, cecum microbiota plays a pivotal role in the modulation of circulating host metabolites upon inulin intervention.

What Is the Impact of Diet on Nutritional Diarrhea Associated with Gut Microbiota in Weaning Piglets: A System Review

Piglets experience severe growth challenges and diarrhea after weaning due to nutritional, social, psychological, environmental, and physiological changes. Among these changes, the nutritional factor plays a key role in postweaning health. Dietary protein, fibre, starch, and electrolyte levels are highly associated with postweaning nutrition diarrhea (PWND). In this review, we mainly discuss the high protein, fibre, resistant starch, and electrolyte imbalance in diets that induce PWND, with a focus on potential mechanisms in weaned piglets.

In Vitro Fermentation Characteristics for Different Ratios of Soluble to Insoluble Dietary Fiber by Fresh Fecal Microbiota from Growing Pigs

This study was conducted to explore the in vitro fermentation characteristics for different ratios of soluble to insoluble dietary fiber in pig fecal microbiota. The fermentation substrates consisted of inulin and a non-starch polysaccharide mixture and were divided into five groups according to different soluble dietary fiber (SDF) to insoluble dietary fiber (IDF) ratios (SDF 25, 50, 75, and 100%). With the increased SDF ratio, the total gas production increased, and the pH in the substrate decreased as the fermentation proceeded. The concentrations of lactic acid, formic acid, and acetic acid increased in the high SDF ratio group, whereas the concentrations of propionic acid and butyric acid increased in the low SDF ratio group. The genera Clostridium_sensu_stricto_1, Ruminococcaceae_NK4A214_group, Christensenellaceae_R-7_group, and Rikenellaceae_RC9_gut_group were enriched in the high SDF ratio group. Correlation analysis indicated that these differential bacteria had the potential to degrade polysaccharides. These results revealed that high SDF ratios could stimulate the proliferation of fibrolytic bacteria, which in turn degrade fibers to produce organic acids and monosaccharides. Collectively, these findings add to our understanding of the mechanisms responsible for interaction between SDF and intestinal microbiota and provide new ideas for the rational use of dietary fiber.

Effects of dietary pectin on the profile and transport of intestinal bile acids in young pigs

Pectin has been known to lower circulating cholesterol by interacting with bile acid (BA) metabolism. The current study was aimed to investigate intestinal BA transport at the molecular level in a pig model. Twelve young pigs (11.05 ± 0.11 kg) were randomly divided into 2 groups and fed corn-soybean meal diets with either 5% pectin or cornstarch for 72 d. In pigs fed with pectin, total cholesterol and low-density lipoprotein cholesterol (LDL-C) were lowered but high-density lipoprotein (HDL-C) was increased (P < 0.05). Serum triglycerides tended to be lower in the pectin-fed animals (P = 0.093), whereas no change was noted in serum total bile acid. Along the length of the intestine, the size and composition of BA pools vary. The ratio of primary, secondary, taurine-conjugated, and glycine-conjugated BAs in the ileal pool was about 46:15:9:30, whereas it was 28:61:1:11 in the cecum and 22:65:3:9 in the colon (P < 0.05). In the feces, lithocholic acid and ursodeoxycholic acid (UDCA) made up of over 97% of the total BA pool. Overall, the ileum had the greatest expression of farnesoid X receptor (FXR) and apical sodium-coupled bile acid transporter (ASBT) than the duodenum, jejunum, cecum, and colon (P < 0.05), whereas organic solute transporters α/β (OSTα/β) gene expression was peaked in the ileum and jejunum (P < 0.05). Expression multidrug resistance protein 2 (MRP2) gradually decreased towards the end of the intestine (P < 0.05). Greater expression of G protein-coupled bile acid receptor and multidrug resistance protein 3 (MRP3) was found in the cecum and colon (P < 0.05). In pigs fed with 5% pectin, only cecal UDCA (P = 0.097) and hyocholic acid (P = 0.088) showed a decreasing tendency. But FXR, ASBT, and MRP2 were upregulated in the ileum and FXR, OSTα/β, MRP2, and MRP3 in the cecum of PEC-fed pigs (P < 0.05). Liver enzymes involved in BA biosynthesis (CYP7A1, CYP27A1, bile acid-CoA synthase, and bile acid-CoA:amino acid N acyltransferase) were not affected by pectin consumption. In conclusion, the abundant distribution of BA transporters and the greater BA pool size suggests the ileum as the major site for intestinal BA reabsorption in pigs. In the ileum, pectin increased in-and-out BA transport on the apical membrane by increasing ASBT and MRP2, but it increased the overall BA transport in the cecum by increasing OSTα/β and MRP3.

A chemical derivatization based UHPLC-LTQ-Orbitrap mass spectrometry method for accurate quantification of short-chain fatty acids in bronchoalveolar lavage fluid of asthma mice

Recent studies have demonstrated the important role of short-chain fatty acids (SCFAs) in the maintenance of homeostasis of respiratory immunity. However, there is still no report focus on the determination of SCFAs level in bronchoalveolar lavage fluid (BALF), the most common sample used for screening biomarkers of the pulmonary diseases. Herein, an ultra-high-performance liquid chromatography with LTQ-Orbitrap mass spectrometer (UHPLC-LTQ-Orbitrap) oriented 3-nitrophenylhydrazine (3-NPH)-based derivatization method was developed for the quantification of SCFAs in BALF. To achieve accurate quantitation, d4-acetate was used as internal standard to compensate for the matrix effects. Method validation showed a good linearity (R² > 0.9992) with wide concentration range, and the intra-day and inter-day precision for determination of eight SCFAs in BALF samples was ≤ 14.79%. The quantitation accuracy, assessed by relative recoveries, ranged from 90% to 110% for target SCFAs at three concentration levels. Matrix effects ranged from 85% to 115%, and the lower limits of quantification of these targeted SCFAs were varied from 3 to 24 nmol/L. The SCFAs-targeted method was then applied to determine the changed levels in BALF samples from OVA-induced asthma mice and normal mice. In addition, the universality of our developed method was also demonstrated by determining the SCFAs concentrations in feces, serum and lung tissue samples from asthma and normal mice. These results indicate that 3-NPH derivatization based UHPLC-LTQ-Orbitrap provides accurate view of global SCFAs alternation in different samples, giving a support to deduce the origin of SCFAs in lung. The present study is of great importance for understanding the role of SCFAs in modulation of host metabolism and immunity.

Spatial Heterogeneity and Co-occurrence of Mucosal and Luminal Microbiome across Swine Intestinal Tract

Pigs are one of the most important economic livestock. Gut microbiota is not only critical to the health but also the production efficiency of pigs. Manipulating gut microbiota relies on the full view of gut microbiome and the understanding of drive forces shaping microbial communities. 16s rDNA sequencing was used to profile microbiota along the longitudinal and radical axes to obtain the topographical map of microbiome in different intestinal compartments in young pigs. Alpha and beta-diversities revealed distinct differences in microbial compositions between the distal ileum and cecum and colon, as well as between the lumen and mucosa. Firmicutes and Proteobacteria dominated in the ileum, constituting 95 and 80% of the luminal and mucosa-attached microbiome. Transitioning from the small intestine to the large intestine, luminal Bacteroidetes increased from 1.69 to 45.98% in the cecum and 40.09% in the colon, while mucosal Bacteroidetes raised from 9 to 35.36% and 27.96%. Concurrently, luminal Firmicutes and Proteobacteria and mucosal-attached Proteobacteria remarkably decreased. By co-occurrence network analyses, Prevotellaceae, Ruminococcaceae, Lachnospiraceae and Veillonellaceae were recognized as the central nodes of luminal microbial network, and Prevotellaceae and Enterobacteriaceae, Caulobacteraceae, Enterococcaceae, Xanthomonadaceae, Pseudomonadaceae were identified as mucosal central nodes. Co-abundance was uncovered among Prevotellaceae, Lachnospiraceae, and Veillonellaceae in the luminal and mucosal microbiome, while opportunistic pathogens from γ-Proteobacteria in the mucosa. Strong co-exclusion was shown between Enterobacteriaceae with Prevotellaceae-centered microbial groups in the lumen. Redundancy analysis found bile acids and short chain fatty acids explained 37.1 and 41% of variations in the luminal microbial composition, respectively. Primary bile acid, taurine- and glycine- conjugated bile acids were positively correlated with Lactobacillaceae, Enterobacteriaceae, Clostridiaceae_1, Peptostreptococcaceae, whereas secondary bile acids, acetate, propionate, butyrate, and valerate were positively correlated with Prevotellaceae, Acidaminococcaceae, Ruminococcaceae, Lachnospiraceae, Desulfovibronaceae, Veillonellaceae. Functional analyses demonstrated that Prevotella, Veillonellaceae, Lachnospiraceae, and Ruminococcaceae were positively correlated with gene functions related to amino acids, energy, cofactors and vitamins metabolism, which are indispensable for the hosts. These results suggested site specific colonization and co-occurrence of swine gut microbiome closely relate to the microenvironment in each niche. Interactions of core gut microbiome greatly contributed to metabolism and/or immunity in the swine intestine.

Functionality and nutritional aspects of microcrystalline cellulose in food

Microcrystalline cellulose (MCC) is among the most commonly used cellulose derivatives in the food industry. In order assess the recent advances of MCC in food product development and its associated nutraceutical implications, google scholar and database of journals subscribed by Jiangnan university, China were used to source literature. Recently published research articles that reported physicochemical properties of MCC for food application or potential application in food and nutraceutical functions were reviewed and major findings outlined. The selected literature reviewed demonstrated that the material has been extensively explored as a functional ingredient in food including meat products, emulsions, beverages, dairy products, bakery, confectionary and filling. The carbohydrate polymer also has many promising applications in functional and nutraceutical food industries. Though widely used as control for many dietary fiber investigations, MCC has been shown to provide positive effects on gastrointestinal physiology, and hypolipidemic effects, influencing the expression of enzymes involved in lipid metabolism. These techno-functional and nutraceutical properties of MCC are influenced by the physicochemical of the material, which are defined by the raw material source and processing conditions. Apart from these functional properties, this review also highlighted limitations and gaps regarding the application of material in food and nutritional realms. Functional, Nutritional and health claims of MCC.