Dietary butyrate, lauric acid and stearic acid improve gut morphology and epithelial cell turnover in weaned piglets

Odd-Chain Fatty Acid-Enriched Fats Improve Growth and Intestinal Morphology and Function in Milk Replacer-Fed Piglets

BACKGROUND

The intestinal development and nutritional needs of piglets after birth are similar to those of human infants.

OBJECTIVES

This study aimed to investigate the effect of different forms of odd-chain fatty acids (OCFAs) on the growth and intestinal morphology and function of milk replacer-fed piglets, as a model for human infants.

METHODS

Forty 7-d-old piglets from 8 sows were randomly assigned into 5 groups (n = 8, each from a different litter) and fed sow milk or milk replacers supplemented with different kinds of fats (control fats, docosahexaenoic acid algal oil-, OCFA algal oil-, and OCFA-enriched fats) for 21 d. One-way analysis of variance was performed to compare the milk replacer-fed piglet groups, and unpaired t test was used to compare sow milk- and milk replacer-fed piglets.

RESULTS

Milk replacers supplemented with OCFA-enriched fats increased the average daily gain (ADG), ratio of villus height to crypt depth, and protein expression of Ki67, phosphorylated (p)-mTOR, p-S6K1, Occludin, Claudin, and ZO-1 in the selected intestines of piglets and decreased the protein expression of p-ULK1, Parkin, and PINK1 to levels similar to those of the sow milk-fed group (P < 0.05).

CONCLUSION

Overall, milk replacers supplemented with OCFA-enriched fats improved the ADG and the intestinal morphology and function of piglets to levels comparable to those of the sow milk-fed piglets.

Dried Whole Black Soldier Fly Larvae Consumption Supports Gestation, Lactation, and Growth in Cats

This study evaluated the consumption of dried whole black soldier fly larvae (DBSFL) to meet the nutritional requirements of gestating and lactating cats and their kittens post-weaning. Queens (n = 8/treatment) were randomly assigned to a control diet or diets containing 20% DBSFL through gestation and lactation. Weaned kittens (n = 8/treatment) were maintained on their dams' diet for 10-weeks. There were no differences (p > 0.05) in the litter size, dietary intake, body weight, or fecal quality of the queens during the trial. The kittens receiving the DBSFL diet consumed more on an absolute or caloric basis than those fed the control diet at week 5 (p = 0.1) and week 10 (p = 0.03) and had higher body weights at weeks 6 through 10 (p < 0.05). The blood and urinalysis parameters were generally within normal ranges, with some variations observed between treatments that were not considered biologically significant. The dry matter, crude protein, and amino acid digestibility levels were higher in kittens fed the DBSFL diet (p = 0.05). These data are the first to demonstrate the safety and efficacy of DBSFL for the gestation and lactation of queens and for the growth of kittens, as well as its suitability in diets for cats of all life stages.

Dietary Iron Alleviates Dextran Sodium Sulfate-Induced Intestinal Injury by Regulating Regeneration of Intestinal Stem Cells in Weaned Mice

Iron deficiency is the most common comorbidity of inflammatory bowel disease (IBD), but the effect of iron supplementation on the repair processes of intestinal injury in weaned mice is unknown. This study aimed to evaluate the potential mechanism of dietary iron on intestinal injury and intestinal regeneration in the dextran sodium sulfate (DSS)-induced colitis of the weaned mouse model. The mice were fed either a control diet containing (45.00 mg/kg Fe) or iron supplemental (448.30 mg/kg Fe) diet for 14 days, followed by a 7-day oral administration of 2.5% DSS to all mice. The result showed that at day 0 of the recovery period (0 DRP), the impact of iron on the gut index and intestinal morphology was found to be more significant in weaned mice compared to adult mice. At 3 DRP, the iron diet alleviated inflammation-induced weight loss, shortening of colon length, thickening of the muscle layer, and disruption of gut morphology. At 0, 3, and 7 DRP, we found that an iron diet increased intestinal stem cell (ISC) viability and protected epithelial integrity. Furthermore, FeSO4 significantly enhanced organoid viability and increased mRNA expression of differentiation, ISC, and retinol metabolism-related marker genes in the organoids compared with the control group. Overall, this study demonstrates that the iron diet accelerates intestinal regeneration after intestinal injury in weaned mice by activating the retinol metabolic pathway to regulate the proliferation and differentiation of ISCs.

Modulation of Eimeria spp. parasite load on productivity parameters in lambs fed with babassu byproduct

This study investigated the modulation of Eimeria spp. parasite load and its impact on productivity parameters in lambs fed varying levels of babassu by-product (BBP). Twenty-four Dorper × Santa Inês lambs naturally infected with Eimeria spp. were divided into four groups and assigned to dietary treatments with increasing levels of BBP inclusion: Control group (0% BBP; n = 6), G1 (5% BBP; n = 6), G2 (10% BBP; n = 6), and G3 (15% BBP; n = 6). Fecal oocyst counts, dry matter intake (DMI), average daily gain (ADG), and apparent digestibility coefficients were monitored throughout the experiment. Results revealed that 9.5% BBP inclusion was associated with the lowest mean oocyst count per gram of feces, without compromising ADG. Nine Eimeria species were identified, with E. crandallis, E. parva and E. ovinoidalis being the most prevalent. Principal component analysis revealed a negative correlation between Eimeria spp. infection intensity and lamb performance, with higher BBP inclusion levels being associated with improved DMI, ADG, and digestibility. These findings suggest that dietary BBP at 9.5% inclusion effectively modulates Eimeria spp. parasite load in lambs while maintaining productivity. Although the exact mechanisms require further investigation, these results highlight BBP as a promising natural alternative for coccidiosis management in sheep production. This natural, sustainable approach offers a promising strategy for coccidiosis management in sheep, particularly in tropical and subtropical production systems.

Effects of dietary supplementation of myristic acid on jejunal mucosa-associated microbiota, mucosal immunity, and growth performance of nursery pigs

The objective of this study was to investigate the effects of myristic acid on jejunal mucosal microbiota, mucosal immunity, and growth performance of nursery pigs. Thirty-six pigs (6.6 ± 0.4 kg of body weight) were assigned to three treatments (n = 12) for 35 d in three phases: (NC) basal diet; (PC) NC + bacitracin; and (MA) NC + myristic acid compound. Pigs were euthanized to collect jejunal mucosa, jejunal tissues, and ileal digesta. The PC increased (p < 0.05) the relative abundance (RA) of Lactobacillus spp., and Bifidobacterium boum than the NC group. The MA increased (p < 0.05) RA of Bifidobacterium dentium and Megasphaera spp. than the NC group. The PC tended to decrease IL-8 (p = 0.053) and protein carbonyl (p = 0.075) whereas IgG (p = 0.051) and IL-8 (p = 0.090) in jejunal mucosa were decreased by the MA. The PC increased (p < 0.05) the villus height to crypt depth ratio than the NC group. Both bacitracin and myristic acid improved the intestinal health and growth performance of nursery pigs. Effects of bacitracin were rather immediate whereas the effects of myristic acid were obtained after a 3-week feeding.

Sustainable Nutritional Strategies for Gut Health in Weaned Pigs: The Role of Reduced Dietary Crude Protein, Organic Acids and Butyrate Production

Weaning in piglets presents significant physiological and immunological challenges, including gut dysbiosis and increased susceptibility to post-weaning diarrhoea (PWD). Abrupt dietary, environmental, and social changes during this period disrupt the intestinal barrier and microbiota, often necessitating antimicrobial use. Sustainable dietary strategies are critical to addressing these issues while reducing reliance on antimicrobials. Reducing dietary crude protein mitigates the availability of undigested proteins for pathogenic bacteria, lowering harmful by-products like ammonia and branched-chain fatty acids, which exacerbate dysbiosis. Organic acid supplementation improves gastric acidification, nutrient absorption, and microbial balance, while also serving as an energy-efficient alternative to traditional grain preservation methods. Increasing intestinal butyrate, a key short-chain fatty acid with anti-inflammatory and gut-protective properties, is particularly promising. Butyrate strengthens intestinal barrier integrity by upregulating tight junction proteins, reduces inflammation by modulating cytokine responses, and promotes anaerobic microbial stability. Exogenous butyrate supplementation via salts provides immediate benefits, while endogenous stimulation through prebiotics (e.g., resistant starch) and probiotics promotes sustained butyrate production. These interventions selectively enhance butyrate-producing bacteria such as Roseburia and Faecalibacterium prausnitzii, further stabilising the gut microbiota. Integrating these strategies can enhance gut integrity, microbial resilience, and immune responses in weaned piglets. Their combination offers a sustainable, antimicrobial-free approach to improving health and productivity in modern pig production systems.

Effects of xylo-oligosaccharide supplementation on the production performance, intestinal morphology, cecal short-chain fatty acid levels, and gut microbiota of laying hens

This study investigated the effects of xylo-oligosaccharide supplementation on the production performance, intestinal morphology, cecal short-chain fatty acid levels, and gut microbiota of laying hens. A total of 800 Lohmann pink layers, each 48 wk old, were randomly divided into 5 dietary treatment groups, namely XOS at 0 (CON), 100 (XOS1), 200 (XOS2), 300 (XOS3) and 400 (X0S4) mg/kg. The experimental period was 24 wk. The results revealed that the egg production rate and the number of eggs laid by each layer between 1 to 12 wk increased as the XOS concentration increased (Plinear < 0.05). The sand-shell egg percentage decreased significantly from 1 to 12 wk in the XOS1, XOS2, and XOS3 groups (PANOVA < 0.05). Compared with the CON group, the 4 XOS dosage groups presented significant increases in the villus height and the ratio of villus height to crypt depth in the jejunum (PANOVA < 0.05), whereas a linear decrease in jejunal crypt depth (Plinear < 0.05) was noted. In addition, XOS supplementation significantly increased the concentrations of butyric acid and isovaleric acid in the caeca (PANOVA < 0.05). High-throughput sequencing analysis of bacterial 16S rRNA revealed that dietary XOS supplementation influenced the cecal microbiota. The alpha diversity analysis indicated that the richness of cecal bacteria was greater in the laying hens fed XOS. The modulation of the cecal microbiota composition upon the addition of XOS was characterized by an increased abundance of Firmicutes and Bifidobacteriaceae, and decreased abundance of Bacteroidetes. At the genus level, dietary XOS supplementation resulted in decreases in the abundances of Bacteroides and Rikenellaceae_RC9_gut_group and an increase in the abundance of Lactobacillus. In conclusion, dietary XOS supplementation improved the production performance of laying hens by increasing the production of short-chain fatty acids and improving their intestinal morphology, which was achieved mainly through changes in the composition of the intestinal microbiota. The recommended level of XOS in the diet of laying hens is 200 mg/kg.

Effects of Hermetia illucens larvae meal and astaxanthin on intestinal histology and expression of tight junction proteins in weaned piglets

The weaning phase in piglets causes significant physiological stress, disrupts intestinal integrity and reduces productivity, necessitating strategies to improve intestinal health and nutrient absorption. While current research highlights the role of diet in mitigating these adverse effects, identifying effective dietary supplements remains a challenge. This study evaluated the effects of Hermetia illucens (HI) larvae meal and astaxanthin (AST) on the intestinal histology of weaned piglets. In a controlled experiment, 48 weaned piglets were divided into six groups and received varying levels of HI larval meal (2.5% and 5%) and AST in their diets. The methodology involved comprehensive histological examinations of the small intestine, assessing absorption area, villi elongation, crypt depth, goblet cells, enterocytes and expression of ileal tight junction (TJ) proteins. The study found that HI larval meal significantly improved nutrient absorption in the jejunum and ileum (p < 0.001), thereby enhancing feed conversion. AST supplementation increased the number of enterocytes (p < 0.001). Both HI larval meal and AST positively affected intestinal morphology and function, increasing muscularis muscle mass and villi elongation (p < 0.001 and p < 0.05, respectively). The 2.5% HI meal improved the villi length to crypt depth ratio and slightly increased the goblet cell count (both p < 0.05). Ki-67 antibody analysis showed increased cell proliferation in the duodenal and jejunal crypts, particularly with the 2.5% HI meal (p < 0.001). Insect meal did not affect TJ protein expression, indicating that it had no effect on intestinal permeability. These findings suggest that HI larval meal and AST can enhance the intestinal wellness and productivity of weaned piglets.

Lauric acid reduces apoptosis by inhibiting FOXO3a-signaling in deoxynivalenol-treated IPEC-J2 cells

Deoxynivalenol (DON) is the most common mycotoxin contaminant of food or feed worldwide and causes disease in animals. Lauric acid (LA) is a medium-chain fatty acid useful for barrier functions such as antimicrobial activity in the intestine of monogastric animals. However, the molecular mechanisms by which lauric acid exerts its effects on the deoxynivalenol-exposed small intestine have not been studied. We used an intestinal porcine epithelial cell line (IPEC-J2) as an in vitro model to explore the molecular mechanism of lauric acid in alleviating deoxynivalenol-induced damage. We found that lauric acid reversed deoxynivalenol-induced reduction in cell viability. Our quantitative real-time polymerase chain reaction results indicated that lauric acid alleviated deoxynivalenol-induced apoptosis through Annexin-V. Additionally, immunofluorescence and Western blotting showed that lauric acid attenuated deoxynivalenol-induced forkhead box O3 (FOXO3a) translocation into the nucleus. These results suggest that lauric acid attenuates forkhead box O3 translocation in the small intestine damaged by deoxynivalenol, thereby reducing apoptosis. In conclusion, this study found that lauric acid alleviates deoxynivalenol-induced damage in intestinal porcine epithelial cell line through various molecular mechanisms.

Nutrition strategies to control post-weaning diarrhea of piglets: From the perspective of feeds

Post-weaning diarrhea (PWD) is a globally significant threat to the swine industry. Historically, antibiotics as well as high doses of zinc oxide and copper sulfate have been commonly used to control PWD. However, the development of bacterial resistance and environmental pollution have created an interest in alternative strategies. In recent years, the research surrounding these alternative strategies and the mechanisms of piglet diarrhea has been continually updated. Mechanically, diarrhea in piglets is a result of an imbalance in intestinal fluid and electrolyte absorption and secretion. In general, enterotoxigenic Escherichia coli (ETEC) and diarrheal viruses are known to cause an imbalance in the absorption and secretion of intestinal fluids and electrolytes in piglets, resulting in diarrhea when Cl- secretion-driven fluid secretion surpasses absorptive capacity. From a perspective of feedstuffs, factors that contribute to imbalances in fluid absorption and secretion in the intestines of weaned piglets include high levels of crude protein (CP), stimulation by certain antigenic proteins, high acid-binding capacity (ABC), and contamination with deoxynivalenol (DON) in the diet. In response, efforts to reduce CP levels in diets, select feedstuffs with lower ABC values, and process feedstuffs using physical, chemical, and biological approaches are important strategies for alleviating PWD in piglets. Additionally, the diet supplementation with additives such as vitamins and natural products can also play a role in reducing the diarrhea incidence in weaned piglets. Here, we examine the mechanisms of absorption and secretion of intestinal fluids and electrolytes in piglets, summarize nutritional strategies to control PWD in piglets from the perspective of feeds, and provide new insights towards future research directions.

Dietary Resveratrol Ameliorates Hepatic Fatty Acid Metabolism and Jejunal Barrier in Offspring Induced by Maternal Oxidized Soybean Oil Challenge

Increasing evidence indicates that maternal exposure to oxidized soybean oil (OSO) causes damage to the mother and offspring. The antioxidant resveratrol (Res) has a variety of health benefits. However, the protective effect of Res on mitigating offspring damage after maternal exposure to OSO and its mechanism remains unclear. Therefore, this study aimed to investigate the effect of Res on hepatic fatty acid metabolism and the jejunal barrier in suckling piglets after maternal OSO exposure. A total of 18 sows in late gestation were randomly assigned to three treatments. The sows were fed with a fresh soybean oil (FSO) diet, an OSO diet, or the OSO diet supplemented with 300 mg/kg Res (OSO + Res), respectively. The results showed that maternal supplementation of Res restored the mRNA levels of genes related to fatty acid metabolism and increased the activities of catalase (CAT) and total superoxide dismutase (T-SOD) in suckling piglets' livers under the OSO challenge. Moreover, the OSO + Res group restored the mRNA levels of occludin and claudin 4 in suckling piglet jejunum compared with the results of the OSO challenges. In summary, supplementation with Res improves hepatic fatty acid metabolism and intestinal barrier function of suckling piglets after maternal OSO challenge during late gestation and lactation.

Chlorogenic acid protects against intestinal inflammation and injury by inactivating the mtDNA-cGAS-STING signaling pathway in broilers under necrotic enteritis challenge

This study aimed to determine the effects of chlorogenic acid (CGA) on the growth performance, intestinal health, immune response, and mitochondrial DNA (mtDNA)-cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway in broilers under necrotic enteritis (NE) challenge. The 180 one-day-old male Cobb 500 broilers with similar body weight of 44.59 ± 1.39 g were randomly allocated into 3 groups. The groups were control diet (Control group), control diet + NE challenge (NE group), and control diet + 500 mg/kg CGA + NE challenge (NE + CGA group), with 6 replicates per treatment. All broilers except the Control group were given sporulated coccidian oocysts (d 14) and Clostridium perfringens (d 19-21) by oral gavage. Our findings showed that CGA improved the growth performance and intestinal morphology in broilers under NE challenge. CGA supplementation elevated the barrier function in broilers under NE challenge, which reflected in the decreased serum concentrations of D-lactate and diamine oxidase, and upregulated jejunal protein expression of occludin. CGA supplementation also improved the immune function, which reflected in the increased concentrations and gene expressions of anti-inflammatory factors, and decreased concentrations and gene expressions of proinflammatory factors. CGA supplementation further enhanced intestinal cell proliferation and differentiation, which manifested in the increased number of goblet cells and positive cells of proliferating cell nuclear antigen on d 28 and 42. Furthermore, CGA supplementation decreased the mtDNA (d 42) and mitochondrial reactive oxygen species levels (d 28 and 42), and increased the mitochondrial membrane potential (d 42) and mitochondrial complex I (d 28 and 42) or III (d 28) activity. Broilers challenged with NE had upregulated jejunal protein expressions of cGAS, phospho-TANK-binding kinase 1, and phospho-interferon regulatory factor 7 compared with the Control group, which were downregulated after CGA supplementation. In conclusion, dietary supplementation CGA could protect against intestinal inflammation and injury by reducing the leakage of mtDNA and inactivating the cGAS-STING signaling pathway in broilers under NE challenge.

Paraprobiotic and postbiotic forms of Bacillus siamensis improved growth, immunity, liver and intestinal health in Lateolabrax maculatus fed soybean meal diet

Live commensal Bacillus siamensis LF4 showed reparative potentials against high SM-induced negative effects, but whether its paraprobiotic (heat-killed B. siamensis, HKBS) and postbiotic (cell-free supernatant, CFS) forms had reparative functions and potential mechanisms are not yet known. In this study, the reparative functions of HKBS and CFS were investigated by establishing an injured model of spotted seabass (Lateolabrax maculatus) treated with dietary high soybean meal (SM). The results showed that HKBS and CFS effectively mitigated growth suppression, immune deficiency, and liver injury induced by dietary high SM. Simultaneously, HKBS and CFS application positively shaped intestinal microbiota by increased the abundance of beneficial bacteria (Fusobacteria, Firmicutes, Bacteroidota, and Cetobacterium) and decreased harmful bacteria (Proteobacteria and Plesiomonasare). Additionally, HKBS and CFS improved SM-induced intestinal injury by restoring intestinal morphology, upregulating the expression of tight junction proteins, anti-inflammatory cytokines, antimicrobial peptides, downregulating the expression of pro-inflammatory cytokines and apoptotic proteins. Furthermore, HKBS and CFS intervention significantly activated TLR2, TLR5 and MyD88 signaling, and eventually inhibited p38 and NF-κB pathways. In conclusion, paraprobiotic (HKBS) and postbiotic (CFS) from B. siamensis LF4 can improve growth, immunity, repair liver and intestinal injury, and shape intestinal microbiota in L. maculatus fed high soybean meal diet, and TLRs/p38 MAPK/NF-κB signal pathways might be involved in those processes. These results will serve as a base for future application of paraprobiotics and postbiotics to prevent and repair SM-induced adverse effects in fish aquaculture.

Enhanced ileum function in weaned piglets via Laminaria digitata and alginate lyase dietary inclusion: A combined proteomics and metabolomics analysis

Laminaria digitata, a brown seaweed with prebiotic properties, can potentially enhance the resilience of weaned piglets to nutritional distress. However, their cell wall polysaccharides elude digestion by monogastric animals' endogenous enzymes. In vitro studies suggest alginate lyase's ability to degrade such polysaccharides. This study aimed to assess the impact of a 10% dietary inclusion of L. digitata and alginate lyase supplementation on the ileum proteome and metabolome, adopting a hypothesis-generating approach. Findings indicated that control piglets escalated glucose usage as an enteric energy source, as evidenced by the increased abundance of PKLR and PCK2 proteins and decreased tissue glucose concentration. Additionally, the inclusion of seaweed fostered a rise in proteins linked to enhanced enterocyte structural integrity (ACTBL2, CRMP1, FLII, EML2 and MYLK), elevated peptidase activity (NAALADL1 and CAPNS1), and heightened anti-inflammatory activity (C3), underscoring improved intestinal function. In addition, seaweed-fed piglets showed a reduced abundance of proteins related to apoptosis (ERN2) and proteolysis (DPP4). Alginate lyase supplementation appeared to amplify the initial effects of seaweed-only feeding, by boosting the number of differential proteins within the same pathways. This amplification is potentially due to increased intracellular nutrient availability, making a compelling case for further exploration of this dietary approach. SIGNIFICANCE: Pig production used to rely heavily on antibiotics and zinc oxide to deal with post-weaning stress in a cost-effective way. Their negative repercussions on public health and the environment have motivated heavy restrictions, and a consequent search for alternative feed ingredients/supplements. One of such alternatives is Laminaria digitata, a brown seaweed whose prebiotic components that can help weaned piglets deal with nutritional stress, by improving their gut health and immune status. However, their recalcitrant cell walls have antinutritional properties, for which alginate lyase supplementation is a possible solution. By evaluating ileal metabolism as influenced by dietary seaweed and enzyme supplementation, we aim at discovering how the weaned piglet adapts to them and what are their effects on this important segment of the digestive system.

Therapeutic potential of dietary phytochemicals from Drynaria quercifolia to modulate gut microbiome: an in silico approach

Drynaria quercifolia is one of the pioneer medicinal plants which exert many beneficial effects on humans. Fatty acids are hydrophobic ligands that act as membrane substrates, metabolic signalling molecules, and metabolic energy sources. It could enhance the mucus production in the intestine which maintain mucosal homeostasis. The inflammatory responses were also regulated by 5-HT receptors. Serotonin 2 A receptors are G-protein coupled receptors targeted by various types of ligands viz. antidepressants, antipsychotics and anti-migraine drugs. The interaction of mucin protein and fatty acid could increase the antimicrobial activity and anti-inflammatory activity of gut microbiome. In this study, dietary phytochemicals were extracted from D. quercifolia and characterized using GC-MS analysis. The result shows presence of 38 various compounds viz. decanoic acid, indole, and dodecanoic acid and etc., Among the all, dodecanoic acid showed good drug likeness and pharmaceutical properties. Target proteins viz. 3IFB (Intestinal fatty acid binding protein) and 7WC4 (5-hydroxytryptamine receptor 2 A) were docked with dodecanoic acid using Auto dock software. The fatty acids produced in the gut could interact with 3IFB and 7WC4 proteins to maintain intestinal integrity and improved gut-brain function respectively. Dodecanoic acid exhibits the highest binding energy with mutated 3IFB (-6.01) than native whereas 7WC4 native protein showed (-7.3 kal/mol) the highest affinity than mutated protein. Structural changes were predicted by using SOPMA and ProSA. Evaluation results indicate that 3IFB was having more stability, good quality, and enhanced affinity than 7WC4. Further, MD simulations were done for 3IFB to check the stability of protein-ligand complex using WebGro platform. The model was investigated by root mean square deviation and fluctuations. Therefore, dodecanoic acids have been considered as a potential agonists and offer opportunities for developing innovative medications for gastrointestinal diseases.Communicated by Ramaswamy H. Sarma.

A blend of medium-chain fatty acids, butyrate, organic acids, and a phenolic compound accelerates microbial maturation in newly weaned piglets

Inclusion of additive blends is a common dietary strategy to manage post-weaning diarrhea and performance in piglets. However, there is limited mechanistic data on how these additives improve outcomes during this period. To evaluate the effects of Presan FX (MCOA) on the intestinal microbiota and metabolome, diets with or without 0.2% MCOA were compared. Pigs fed MCOA showed improved whole-body metabolism 7 days post-weaning, with decreased (P < 0.05) creatine, creatinine and β-hydroxybutyrate. Alterations in bile-associated metabolites and cholic acid were also observed at the same time-point (P < 0.05), suggesting MCOA increased bile acid production and secretion. Increased cholic acid was accompanied by increased tryptophan metabolites including indole-3-propionic acid (IPA) in systemic circulation (P = 0.004). An accompanying tendency toward increased Lactobacillus sp. in the small intestine was observed (P = 0.05). Many lactobacilli have bile acid tolerance mechanisms and contribute to production of IPA, suggesting increased bile acid production resulted in increased abundance of lactobacilli capable of tryptophan fermentation. Tryptophan metabolism is associated with the mature pig microbiota and many tryptophan metabolites such as IPA are considered beneficial to gut barrier function. In conclusion, MCOA may help maintain tissue metabolism and aid in microbiota re-assembly through bile acid production and secretion.

Effect of Nanomaterials on Gut Microbiota

Nanomaterials are widely employed in everyday life, including food and engineering. Food additives on a nanoscale can enter the body via the digestive tract. The human gut microbiota is a dynamically balanced ecosystem composed of a multitude of microorganisms that play a crucial role in maintaining the proper physiological function of the digestive tract and the body's endocrine coordination. While the antibacterial capabilities of nanomaterials have received much interest in recent years, their impacts on gut microbiota ought to be cautioned about and explored. Nanomaterials exhibit good antibacterial capabilities in vitro. Animal studies have revealed that oral exposure to nanomaterials inhibits probiotic reproduction, stimulates the inflammatory response of the gut immune system, increases opportunistic infections, and changes the composition and structure of the gut microbiota. This article provides an overview of the impacts of nanomaterials, particularly titanium dioxide nanoparticles (TiO₂ NPs), on the gut microbiota. It advances nanomaterial safety research and offers a scientific foundation for the prevention, control, and treatment of illnesses associated with gut microbiota abnormalities.