Medium-chain fatty acids and monoglycerides as feed additives for pig production: towards gut health improvement and feed pathogen mitigation

Medium-chain fatty acids and monoglycerides: Nanoarchitectonics-based insights into molecular self-assembly, membrane interactions, and applications

Medium-chain fatty acids (FAs) and monoglycerides (MGs) with saturated 6- to 12‑carbon long tails are single-chain lipid amphiphiles that demonstrate significant application merits. Key examples include their antimicrobial activity against antibiotic-resistant bacteria and emerging viral threats as well as innovations in oral pharmaceutics and biorenewable chemical production. These diverse functionalities are enabled by FA and MG self-assembly and their interactions with biological membranes. However, an integrated viewpoint connecting interfacial science principles to the broader application scope remains lacking. The objective of this review is to cover the latest progress in medium-chain FA and MG research and to build connections between molecular self-assembly, membrane interactions, and applications. By taking a bottom-up nanoarchitectonics perspective, we first examine molecular self-assembly principles, including ionization properties and formation of colloidal nanostructures such as micelles and vesicles. We then discuss membrane interaction concepts and experimental findings that illustrate how medium-chain FAs and MGs distinctly interact with phospholipid membranes. Based on this foundation, we highlight cutting-edge applications in medicine, agriculture, drug delivery, and sustainability, linking these advances to interfacial science concepts. In addition, we emphasize the growing convergence of experimental, theoretical, and computational approaches and offer a forward-looking perspective on future research needs and application opportunities.

Effects of monoglyceride blend on performance and intestinal health status of piglets fed diets without growth promoters

The study aimed to evaluate the effects of supplementing monoglyceride blend in diets without growth promoters on performance, diarrhea occurrence, blood profile, intestinal morphology and pH, mRNA expression of nutrient transporters, inflammatory markers, antioxidant enzymes, and junction proteins in weaned piglets. Forty piglets were randomly allocated to five groups fed the following diets: control (C), or supplemented with 0.75 g/kg of a blend of fatty acids in powder form (PA), or with 3.00 g/kg of a blend of fatty acids in powder form (HPA), or with 0.50 g/kg of a blend of fatty acids in liquid form (LA), or with 2.00 g/kg of a blend of fatty acids in liquid form (HLA). The LA and PA diets reduced (P < 0.05) the occurrence of diarrhea. The pH of intestinal contents was reduced (P < 0.05) in piglets fed monoglycerides blend. Fecal E. coli count tended (0.05 ≤ P < 0.1) to be reduced in piglets receiving all supplemented diets. LA diet increased (P < 0.05) villus height in the duodenum, while others tended to increase it (0.05 ≤  P < 0.1). In the jejunum, all supplemented diets increased (P < 0.05) the goblet cell proportion. In the ileum, PA diet reduced (P < 0.05) crypt depth and increased (P < 0.05) villus: crypt ratio, and PA, HPA, and HLA diets increased (P < 0.05) goblet cell proportion. In the ileum, HPA and LA diets tended to reduce (0.05 ≤  P < 0.1) crypt depth and Peyer's patch. In the jejunum, LA and HLA diets increased (P < 0.05) the expression of Occludin and HPA increased the expression of Interleukin-10. In conclusion, the supplementation with a monoglyceride blend improves intestinal health and morphology, and local immune response in piglets fed diets without growth promoters.

Solvent-Free Microfluidic Fabrication of Antimicrobial Lipid Nanoparticles

Antimicrobial lipid nanoparticles composed of monoglycerides offer a promising strategy to inhibit membrane-enveloped viral and bacterial pathogens. However, previous efforts mainly focused on fabricating nanoparticles from long-chain monoglycerides, which lack intrinsic antimicrobial activity but contribute to nanoparticle stability and structural integrity. In contrast, shorter-chain monoglycerides often exhibit potent antimicrobial effects but do not self-assemble into colloidally stable nanoparticles and lose efficacy upon dilution. To overcome these limitations and incorporate antimicrobial monoglycerides into a stable nanoparticle configuration, we report a solvent-free microfluidic fabrication strategy that combines the functional characteristics of different monoglycerides to prepare interfacially active, monoglyceride-based nanoparticles with mixed compositions that display potent antibacterial activity. Unlike conventional microfluidic mixing methods that rely on volatile organic solvents, our approach utilizes pharmaceutical-grade materials and does not require organic solvent removal, hence eliminating the need for a dialysis step postfabrication. Dynamic light scattering (DLS) and zeta potential measurements verified that the fabricated nanoparticles had ∼250-350 nm diameters and exhibited high colloidal stability whereas the antibacterial activity of the nanoparticles against Staphylococcus aureus bacteria depended strongly on the nanoparticle composition. Nanoparticles composed of glycerol monooleate alone were inactive, while the inclusion of glycerol monolaurate slightly enhanced antibacterial activity. Surprisingly, the further addition of glycerol monobehenate or glycerol dibehenate─previously considered inactive structural components that are used to improve nanoparticle cohesion─boosted antibacterial potency by up to 270-fold. Biophysical experiments showed that nanoparticle compositions with greater antibacterial activity induced more pronounced membrane disruption, as observed in quartz crystal microbalance-dissipation and electrochemical impedance spectroscopy measurements. These findings demonstrate that combining different monoglycerides can significantly enhance the antibacterial activity of lipid-based nanoparticles and underscore the potential of membrane biophysics approaches to guide performance optimization, highlighting the capability to tune membrane-disruptive properties in physiologically relevant pH conditions.

Impacts of zinc caproate supplementation on growth performance, intestinal health, anti-inflammatory activity, and Zn homeostasis in weaned piglets challenged with Escherichia coli K88

BACKGROUND

Enterotoxigenic Escherichia coli (ETEC) is one of the primary causes of diarrhea in piglets, creating substantial economic losses in the swine farming industry worldwide. This study aimed to investigate the impacts of zinc caproate (ZnCA, C12H22O4Zn) on the intestinal health, growth performance, inflammatory status, and Zn homeostasis of weaned piglets challenged with ETEC K88. In total, 48 weaned piglets (Duroc × Landrace × Yorkshire, 7.78 ± 0.19 kg, 28 d) were selected for a 21-d experiment. Each experimental treatment consisted of 6 replicate pens with 2 piglets each. The treatment conditions were as follows: i) a basal diet (CON), ii) a basal diet + ETEC K88 (NC), iii) a basal diet + 2,500 mg/kg of Zn (provided as zinc oxide, ZnO) + ETEC K88 (PC), and iv) a basal diet + 1,600 mg/kg of Zn (provided as ZnCA) + ETEC K88 (ZnCA).

RESULTS

The addition of 1,600 mg/kg ZnCA to the diet of post-weaning piglets effectively enhanced growth performance and nutrient digestibility and reduced the incidence of diarrhea and inflammatory reactions caused by ETEC K88 infection. These therapeutic effects were comparable to those of pharmacological doses of ZnO. In terms of improving intestinal health and Zn homeostasis in post-weaning piglets challenged with ETEC K88, the effectiveness of 1,600 mg/kg ZnCA surpassed that of pharmacological doses of ZnO.

CONCLUSIONS

Overall, under the experimental conditions of this study, ZnCA exhibited the potential to reduce the pharmacological dosage of ZnO while improving intestinal health and Zn homeostasis in weaned piglets.

Antibiotics and Opportunities of Their Alternatives in Pig Production: Mechanisms Through Modulating Intestinal Microbiota on Intestinal Health and Growth

Antibiotics at subtherapeutic levels have been used in pig diets as antimicrobial growth promoters. However, concerns about antibiotic resistance have increased the demand for alternatives to these antimicrobial growth promoters. This review paper explores the mechanisms through which antimicrobial growth promoters and their alternatives exert their antimicrobial effects. Additionally, this systemic review also covers how modulation of intestinal microbiota by antimicrobial growth promoters or their alternatives affects intestinal health and, subsequently, growth of pigs. The mechanisms and effects of antimicrobial growth promoters and their alternatives on intestinal microbiota, intestinal health, and growth are diverse and inconsistent. Therefore, pig producers should carefully assess which alternative is the most effective for optimizing both profitability and the health status of pigs in their production system.

Neonatal and maternal dietary interventions driving microbiota and functionality in piglet gut compartments

Feed additives aiming to improve gastrointestinal health are frequently supplied to piglets after weaning (d28) but might be more effective when administered before weaning. In this period, feed additives can either be administered directly to neonates, or indirectly via sow's feed. It is yet unknown what the effect of the administration route is on gut functionality and health in the piglets. Therefore, we compared the effect of different dietary interventions on gut functionality after maternal administration (lactation feed) to the neonatal administration route (oral gavage). These feed interventions included medium chain fatty acids (MCFA), beta-glucans (BG), and galacto-oligosaccharides (GOS). For the maternal administration route, MCFA showed a significant difference in alpha diversity parameter, observed species at d1 and one differentially expressed gene (DEG), and 99 DEG at d31. Pathway enrichment analysis showed association to immune processes and metabolism. For BG, only 21 DEG were observed at d31, these DEGs were associated to signal transduction and sympathetic nerve pathway. For GOS, 816 DEG were observed for GOS at d1, and 77 at d31, where DEGs at d1 were associated to immune processes. For the neonatal administration route, MCFA showed 94 DEG and GOS 6 DEG. Where DEGs in MCFA were mainly associated to cell adhesion processes. When comparing the administration routes directly between treatment groups, we observed significant differences in alpha diversity parameters, observed species at d31 for MCFA, Shannon for GOS, as well as for beta diversity in GOS. For MCFA 515 DEG were observed, for BG 503 DEG, and for GOS 996 DEG. Where for MCFA most pathways were associated to immunological processes, BG showed more metabolism, and GOS mainly metabolism with a few immunological processes. The type of intervention and the administration route influence gut functionality of the piglets. MCFA administration led to a more differentially orchestrated response when comparing the neonatal and maternal administration route then the other two additives. This implies that for each nutritional intervention in early life of a pig the optimal route of administration needs to be determined.

Hermetia illucens larvae oil as an alternative lipid source: Effects on immune function, antioxidant activity, and inflammatory response in gilthead seabream juveniles

Hermetia illucens larvae oil (HIO) is a promising new ingredient that can potentially be an alternative lipid source in aquafeeds. To assess its viability in gilthead seabream juvenile diets, a 10-week feeding trial was performed, and the effects on antioxidant, immune, and inflammatory responses were evaluated. Four diets were formulated to include HIO at increasing levels: 0, 4, 7.9, and 9.5 %, replacing a vegetable oil mix at 0, 42 %, 84 %, and 100 %, respectively. At the end of the trial, no significant changes were detected in the plasma immune humoral parameters, except for a linear increase in plasma peroxidase activity. Hepatic lipid peroxidation (LPO) remained unchanged, while the activity of antioxidant enzymes showed a linear increase corresponding to the level of dietary HIO inclusion. Fish fed the HIO diets exhibited lower intestinal LPO, and no differences between groups were observed in the activity of the oxidative stress-related enzymes. Regarding the inflammation-related genes, the different diets did not affect interleukin-1β and transforming growth factor β expressions in the intestine. In contrast, upregulation of tumor necrosis factor α and interleukin-10 was observed, being higher in fish fed the diet with total vegetable oil replacement than the others. In conclusion, these findings suggest that Hermetia illucens larvae oil can be included at levels up to 7.9 % of gilthead seabream juvenile diets without compromising their immune, antioxidant, and inflammatory responses while enhancing intestinal LPO.

Dietary supplementation of blend of organic acids and monoglycerides alleviated diarrhea and systemic inflammation of weaned pigs experimentally infected with enterotoxigenic Escherichia coli F18

BACKGROUND

The emergence of antibiotic resistant microorganisms associated with conventional swine production practices has increased interest in acid-based compounds having antimicrobial properties and other biological functions as nutritional interventions. Despite the interest in organic acids and monoglycerides, few studies have examined the effects of the combination of these acid-based additives in weaned pigs under disease challenge conditions. Therefore, this study aimed to investigate the effects of dietary supplementation with blend of organic acids and/or medium-chain fatty acid monoglycerides on intestinal health and systemic immunity of weaned pigs experimentally infected with an enterotoxigenic Escherichia coli (ETEC) F18 at 4-week of age.

RESULTS

Dietary supplementation of organic acids, monoglycerides, or both organic acids and monoglycerides (combination) reduced (P < 0.05) the diarrhea frequency of ETEC F18-infected pigs throughout the experimental period (d -7 to 21 post-inoculation). This is consistent with the reduced (P < 0.05) proportion of β-hemolytic coliforms in feces observed for the organic acid and combination treatments on d 10 post-inoculation. Supplementation of organic acids, monoglycerides, or combination also reduced (P < 0.05) bacterial translocation in mesenteric lymph nodes on d 21 post-inoculation. Pigs fed with monoglycerides or combination had lower (P < 0.05) white blood cells on d 5 post-inoculation, and pigs fed the combination also had lower (P < 0.05) lymphocytes than pigs in control group. Monoglyceride supplementation increased (P < 0.05) white blood cells and neutrophils compared with control group on d 14 post-inoculation. However, supplementation with organic acid blend, monoglyceride blend, or combination did not affect growth performance in this experiment.

CONCLUSIONS

Supplementation with monoglycerides or organic acids alone or in combination improves the detrimental effects of ETEC F18 infection in weaned pigs, as indicated by reduced diarrhea, fecal shedding of β-hemolytic coliforms, and bacterial translocation, and thus enhancing disease resistance. Monoglycerides reduced the inflammatory response during peak infection, but their immunomodulatory and possible synergistic effects with organic acids need to be further investigated.

The Role of Nutrition Across Production Stages to Improve Sow Longevity

Modern hyperprolific sows are increasingly susceptible to health challenges. Their rapid growth rates predispose them to locomotor disorders, while high metabolic demands, reduced backfat thickness, and increased protein accretion heighten their vulnerability to heat stress and dystocia. Additionally, prolonged farrowing negatively affects the oxidative and inflammatory status of these females. Additionally, prevalent conditions such as gastric ulcers and cystitis raise ethical, welfare, and economic concerns. Despite the several studies related to sow nutrition, there are no studies which compile and extrapolate nutrition approaches from the rearing period and their impact on sows' health and longevity. Also, the aim of our review was to shed light on gaps that require further investigation. Controlling body condition scores is crucial for maximizing productivity in sows. During gestation, high-fiber diets help maintain optimal body condition and prevent constipation, particularly during the peripartum period. Antioxidants offer a range of beneficial effects during this critical phase. Additionally, probiotics and acidifiers can enhance gut health and lower the risk of genitourinary infections. On the day of farrowing, energy supplementation emerges as a promising strategy to reduce farrowing duration. Collectively, these strategies address major health challenges, enhancing welfare and promoting sow's longevity.

Feeding Sows with Multi-Species Probiotics During Late Pregnancy and the Lactating Period Influences IgA Concentration in Colostrum and Subsequently Increases the Survival Rate of Piglets in Porcine Epidemic Diarrhea Outbreak Herd

Porcine epidemic diarrhea (PED) virus is an important cause of diarrhea in sows and piglets [...].

Development of a water-dispersible antimicrobial lipid mixture to inhibit African swine fever virus and other enveloped viruses

Medium-chain antimicrobial lipids are promising antiviral agents to inhibit membrane-enveloped viruses such as African swine fever virus (ASFV) and influenza A virus (IAV) in livestock applications. However, current uses are limited to feed pathogen mitigation due to low aqueous solubility and the development of water-dispersible lipid formulations is needed for broader application usage. In this study, we report a water-dispersible antimicrobial lipid mixture of monoglycerides and lactylates that can inhibit ASFV and IAV and exhibits antiviral properties in drinking water and feed matrices. The lipid mixture reduced the viral infectivity of membrane-enveloped ASFV and IAV in aqueous solution in a dose-dependent manner but was inactive against non-enveloped encephalomyocarditis virus (EMCV). Additional ASFV experiments supported that the lipid mixture is virucidal, which was corroborated by polymerase chain reaction (PCR) experiments. Feed mitigation experiments demonstrated that the lipid mixture can also inhibit ASFV infectivity and affected the conformational properties of ASFV p72 structural protein in virus-spiked feed. Mechanistic experiments identified that the lipid mixture rapidly disrupted phospholipid membranes in a micelle-dependent manner, which aligns with the virological data while higher concentrations were needed for virucidal activity than for the onset of membrane disruption. These findings support that water-dispersible antimicrobial lipid mixtures can effectively inhibit ASFV and IAV and have practical advantages for drinking water applications compared to existing medium-chain antimicrobial lipid mitigant options that are formulated as dry powders or oils for in-feed applications.

Specialized Feed-Additive Blends of Short- and Medium-Chain Fatty Acids Improve Sow and Pig Performance During Nursery and Post-Weaning Phase

The present study investigates the impact of supplementing diets with a synergistic blend of short- and medium-chain fatty acids (SCFAs-MCFAs) during the peripartum and lactation phases on early microbial colonization and the subsequent growth performance of newborn pigs. The experiment involved 72 sows and their litters, with a follow-up on 528 weaned pigs. Sows were fed either a control diet or a diet supplemented with SCFAs-MCFAs and the pigs were monitored for their growth performance and microbial populations. Subsequently, selected weaned pigs were allotted to an SCFAs-MCFAs diet according to the maternal diet. Results showed that SCFAs-MCFAs supplementation led to reduced backfat loss in sows and improved pig weight and uniformity at weaning (p < 0.05). Additionally, suckling pigs exhibited significant shifts in gut microbiota, including increased lactic acid bacteria and reduced Streptococcus suis populations (p < 0.05). Although there was no influence of maternal diet on pig growth after weaning, there was a modulation on bacterial populations at 7 and 35 days post-weaning. Pigs fed SCFAs-MCFAs demonstrated improved feed efficiency with notable reductions in E. coli and Streptococcus suis counts. The findings suggest that maternal dietary supplementation with SCFAs-MCFAs can positively influence both sow and pig performance, offering a potential strategy to enhance productivity and health in the commercial swine production.

Influence of medium chain fatty acids on selected microbes and on in vitro ruminal fermentation of air-exposed corn silage

Several medium chain fatty acids and different chemical forms of these acids were evaluated in vitro as treatments of aerobically-exposed corn silage against spoilage and pathogenic microbes and for effects on rumen fermentation. Treatments were control (no additive), myristate (MY), laurate (LA), monolaurin (MLA), methyl ester laurate (MELA), a blend of mono-, di- and triglycerides of laurate (BLA), and monocaprylate (MC). After 24 h of aerobic incubation (37°C), yeast and mold growth were not influenced (P > 0.05) by treatments, while the net growth of lactic acid bacteria was decreased, albeit slightly, compared to that by untreated controls (P < 0.01) by all treatments of the air-exposed corn silage. Compared with controls, wild-type enterococci were decreased (P < 0.01) in MLA, MELA, and BLA. Staphylococcus aureus was reduced (P < 0.01) with MLA, MELA, BLA, and MC. Total aerobes showed reductions (P < 0.01) with MLA, BLA, and MC. Listeria monocytogenes numbers were reduced (P < 0.01) with MELA. Anaerobic incubation (24 h; 39°C) of ruminal fluid (10 mL) with 0.2 g air-exposed and MCFA-treated corn silage revealed higher hydrogen accumulations (P < 0.01) with MLA and MC over the control treatment. Methane was decreased (P < 0.01) solely by MLA. There was an increase (P < 0.01) of acetate with MELA and MC; of propionate with MELA or by BLA; and of butyrate with MLA, MELA, BLA, and MC. Total VFA, hexose fermented, and ammonia were increased (P < 0.01) with MELA, BLA, and MC. The acetate:propionate ratio was increased (P < 0.01) with MC. The results showed that treatment of air-exposed corn silage with esterified MCFA had no effect on yeasts and molds but prevented propagation or reduced populations of some unwanted and potentially desirable bacteria. Modest methane reduction was seen during in vitro incubation of rumen fluid suspensions with MLA-treated silage and ammonia accumulations were increased in esterified MCFA-treated silage. Little, if any, other detrimental effects on beneficial ruminal fermentation characteristics were observed.

Conversion of wine lees and waste activated sludge into caproate and heptanoate: Thermodynamic and microbiological insights

In this study, wine lees and waste activated sludge (WAS) were co-fermented for the first time in a 4:1 ratio (COD basis) at 20, 40, 70 and 100 gCOD/L, in batch at 37 °C and pH 7.0. The substrates were successfully converted to caproate (C6) and heptanoate (C7) with a high selectivity (40.2 % at 40 gCOD/L). The rapidly-growing chain-elongating microbiome was enriched inClostridiaceaeandOscillospiraceae, representing together 3.4-8.8 % of the community. Substrate concentrations higher than 40 gCOD/L negatively affected C6 and C7 selectivities and yields, probably due to microbial inhibition by high ethanol concentrations (15.82-22.93 g/L). At 70 and 100 gCOD/L, chain elongation shifted from ethanol-based to lactate-based, with a microbiome enriched in the lactic acid bacteriaRoseburia intestinalis(27.3 %) andEnterococcus hirae(13.8 %). The partial pressure of H2(pH2) was identified by thermodynamic analysis as a fundamental parameter for controlling ethanol oxidation and improving C6 and C7 selectivities.

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.

Effects of monoglycerides of short and medium chain fatty acids and cinnamaldehyde blend on the growth, survival, immune responses, and tolerance to hypoxic stress of Pacific white shrimp (Litopenaeus vannamei)

Free fatty acids have long been used as dietary supplements in aquaculture, but the application of monoglycerides has increased interest in more recent times. The study aimed to investigate the effects of dietary short- and medium-chain fatty acid monoglyceride and cinnamaldehyde (SMMG) on the growth performance, survival, immune responses, and tolerance to hypoxic stress of Pacific white shrimp (Litopenaeus vannamei). In Experiment 1, shrimp post-larvae were divided into 4 groups with 6 replicates and fed with diets supplemented with 0 (control), 0.3, 0.4, and 0.5% diet for 30 days. The final body weight and survival rate were determined. In Experiment 2, the juvenile shrimp from Experiment 1 were subjected to hypoxic stress conditions (dissolved oxygen level 2-2.5 mg/L) for 14 days, then the specific growth rate (SGR), survival rate, intestinal Vibrio spp. count, immune responses, and histopathological change of the hepatopancreas were analyzed. Following the 30-day feeding trial, the results revealed that the final body weight and survival of the 0.3-0.5% SMMG groups (2.81-3.06 g and 74.00-84.33%, respectively) were significantly higher than the control shrimp (1.96 g and 68.33%, respectively). In the hypoxic stress experiment, the survival rates of shrimp fed 0.4-0.5% SMMG (71.67-80.00%) were significantly higher than the control (51.67%). Although the SGR were not affected by SMMG supplementation, all immune parameters evaluated were significantly enhanced, and the intestinal Vibrio spp. counts were significantly decreased in the 0.4-0.5% SMMG-fed shrimp; the histopathological structure of the hepatopancreas was also improved in these shrimp compared to the control. Our findings indicated that SMMG as a feed additive has beneficial effects in improving shrimp health and increasing tolerance to hypoxic conditions.

Deciphering the reduction of antibiotic resistance genes (ARGs) during medium-chain fatty acids production from waste activated sludge: Driven by inhibition of ARGs transmission and shift of microbial community

Medium-chain fatty acids (MCFAs) production from waste activated sludge (WAS) by chain extension (CE) is a promising technology. However, the effects and mechanisms of CE process on the fate of antibiotic resistance genes (ARGs) remain unclear. In this study, the results showed that the removal efficiency of ARGs was 81.15 % in CE process, suggesting its efficacy in reducing environmental risks. Further, the observed decrease in mobile genetic elements (MGEs) indicated that CE process restricted the horizontal gene transfer (HGT). Complementing this, the increase in soluble organic matters and extracellular 16 S rDNA confirmed that MCFAs production caused bacterial damage. Decreased intracellular ARGs and increased extracellular ARGs further revealed that MCFAs production impaired ARGs hosts, thereby limiting the vertical gene transfer (VGT) of ARGs. Shift of microbial community combined with co-occurrence network analysis demonstrated that functional bacteria without host potential for ARGs were enriched, but potential ARGs and MGEs hosts decreased, showing the role of functional bacterial phylogeny and selection pressure of MCFAs in reducing ARGs. Finally, partial least squares path model was used to systematic verify the mechanism of ARGs removal in CE process, which was attributed to the inhibition of ARGs transmission (HGT and VGT) and shift of microbial community.

Medium-chain carboxylates production from plant waste: kinetic study and effect of an enriched microbiome

BACKGROUND

The need for addition of external electron donors such as ethanol or lactate impairs the economic viability of chain elongation (CE) processes for the production of medium-chain carboxylates (MCC). However, using feedstocks with inherent electron donors such as silages of waste biomass can improve the economics. Moreover, the use of an appropriate inoculum is critical to the overall efficiency of the CE process, as the production of a desired MCC can significantly be influenced by the presence or absence of specific microorganisms and their metabolic interactions. Beyond, it is necessary to generate data that can be used for reactor design, simulation and optimization of a given CE process. Such data can be obtained using appropriate mathematical models to predict the dynamics of the CE process.

RESULTS

In batch experiments using silages of sugar beet leaves, cassava leaves, and Elodea/wheat straw as substrates, caproate was the only MCC produced with maximum yields of 1.97, 3.48, and 0.88 g/kgVS, respectively. The MCC concentrations were accurately predicted with the modified Gompertz model. In a semi-continuous fermentation with ensiled sugar beet leaves as substrate and digestate from a biogas reactor as the sole inoculum, a prolonged lag phase of 7 days was observed for the production of MCC (C6-C8). The lag phase was significantly shortened by at least 4 days when an enriched inoculum was added to the system. With the enriched inoculum, an MCC yield of 93.67 g/kgVS and a productivity of 2.05 gMCC/L/d were achieved. Without the enriched inoculum, MCC yield and productivity were 43.30 g/kgVS and 0.95 gMCC/L/d, respectively. The higher MCC production was accompanied by higher relative abundances of Lachnospiraceae and Eubacteriaceae.

CONCLUSIONS

Ensiled waste biomass is a suitable substrate for MCC production using CE. For an enhanced production of MCC from ensiled sugar beet leaves, the use of an enriched inoculum is recommended for a fast process start and high production performance.

Dietary nutrition, intestinal microbiota dysbiosis and post-weaning diarrhea in piglets

Weaning is a critical transitional point in the life cycle of piglets. Early weaning can lead to post-weaning syndrome, destroy the intestinal barrier function and microbiota homeostasis, cause diarrhea and threaten the health of piglets. The nutritional components of milk and solid foods consumed by newborn animals can affect the diversity and structure of their intestinal microbiota, and regulate post-weaning diarrhea in piglets. Therefore, this paper reviews the effects and mechanisms of different nutrients, including protein, dietary fiber, dietary fatty acids and dietary electrolyte balance, on diarrhea and health of piglets by regulating intestinal function. Protein is an essential nutrient for the growth of piglets; however, excessive intake will cause many harmful effects, such as allergic reactions, intestinal barrier dysfunction and pathogenic growth, eventually aggravating piglet diarrhea. Dietary fiber is a nutrient that alleviates post-weaning diarrhea in piglets, which is related to its promotion of intestinal epithelial integrity, microbial homeostasis and the production of short-chain fatty acids. In addition, dietary fatty acids and dietary electrolyte balance can also facilitate the growth, function and health of piglets by regulating intestinal epithelial function, immune system and microbiota. Thus, a targeted control of dietary components to promote the establishment of a healthy bacterial community is a significant method for preventing nutritional diarrhea in weaned piglets.

A comprehensive review of medium chain monoglycerides on metabolic pathways, nutritional and functional properties, nanotechnology formulations and applications in food system

A large and growing body of literature has investigated the broad antibacterial spectrum and strong synergistic antimicrobial activity of medium chain monoglycerides (MCMs) have been widely investigated. Recently, more and more researches have focused on the regulation of MCMs on metabolic health and gut microbiota both in vivo and in vitro. The current review summarizes the digestion, absorption and metabolism of MCMs. Subsequently, it focuses on the functional and nutritional properties of MCMs, including the antibacterial and antiviral characteristics, the modulation of metabolic balance, the regulation of gut microbiota, and the improvement in intestinal health. Additionally, we discuss the most recent developments and application of MCMs using nanotechnologies in food industry, poultry and pharmaceutical industry. Additionally, we analyze recent application examples of MCMs and their nanotechnology formation used in food. The development of nanotechnology platforms facilitating molecular encapsulation and functional presentation contribute to the application of hydrophobic fatty acids and monoglycerides in food preservation and their antibacterial effectiveness. This study emphasizes the metabolic mechanisms and biological activity of MCMs by summarizing the prevailing state of knowledge on this topic, as well as providing insights into prospective techniques for developing the beneficial applications of MCMs to realize the industrialized production.

The application of omics technologies for understanding tropical plants-based bioactive compounds in ruminants: a review

Finding out how diet impacts health and metabolism while concentrating on the functional qualities and bioactive components of food is the crucial scientific objective of nutritional research. The complex relationship between metabolism and nutrition could be investigated with cutting-edge "omics" and bioinformatics techniques. This review paper provides an overview of the use of omics technologies in nutritional research, with a particular emphasis on the new applications of transcriptomics, proteomics, metabolomics, and genomes in functional and biological activity research on ruminant livestock and products in the tropical regions. A wealth of knowledge has been uncovered regarding the regulation and use of numerous physiological and pathological processes by gene, mRNA, protein, and metabolite expressions under various physiological situations and guidelines. In particular, the components of meat and milk were assessed using omics research utilizing the various methods of transcriptomics, proteomics, metabolomics, and genomes. The goal of this review is to use omics technologies-which have been steadily gaining popularity as technological tools-to develop new nutritional, genetic, and leadership strategies to improve animal products and their quality control. We also present an overview of the new applications of omics technologies in cattle production and employ nutriomics and foodomics technologies to investigate the microbes in the rumen ecology. Thus, the application of state-of-the-art omics technology may aid in our understanding of how species and/or breeds adapt, and the sustainability of tropical animal production, in the long run, is becoming increasingly important as a means of mitigating the consequences of climate change.

Butyric acid glycerides as substitutes for antibiotics as growth enhancers in the diet of nursery piglets

This study aimed to determine whether the addition of butyric acid glycerides as substitutes to conventional growth promoters can provide adequate zootechnical performance and intestinal health in healthy piglets in the nursery phase. We used 90 male piglets (average weight of 6.5 kg) subdivided into five treatments with six replicates per treatment. The treatments had the same basal diet: NC-negative control (without growth promoter), PC-positive control (with gentamicin, oral), PSB-protected sodium butyrate, FSB-free sodium butyrate, and TRI-tributyrin. In these animals, zootechnical performance was evaluated on days 1, 10, 20 and 39, microbiological analysis on days 14 and 39, hematocrit, blood biochemistry and intestinal histology, intestinal oxidation and antioxidation on day 39. The average daily weight gain was higher in the TRI group on days 21 to 39 in the nursery (P = 0.03), with more significant weight gain from 1 to 39 days (P = 0.05). There were higher leukocyte counts in the PC group than in the TRI group and higher lymphocyte counts in the PC treatment than in the NC or TRI groups. Escherichia coli counts were lower in the PC, followed by the PSB and TRI groups on day 39 (P = 0.01). Lower crypt depths were found in the TRI and FSB groups, followed by PC, than in the NC group (P = 0.01). Higher values for crypt villosity ratio were found in the FSB and TRI groups than in the NC group (P = 0.05). Lower lipid peroxidation was found in analyzes of serum oxidative status (LPO: P = 0.01), associated with greater activities of superoxide dismutase - SOD (P = 0.08), glutathione S-transferase - GST (P = 0.09) in PSB and TRI groups than in the NC group. In conclusion, the use of butyric acid in the form of tributyrin can be used as growth enhancers in piglets in the nursery phase.

The differential crosstalk of the skin-gut microbiome axis as a new emerging actor in systemic sclerosis

OBJECTIVES

We characterized the microbiota in SSc, focusing on the skin-oral-gut axis and the serum and faecal free fatty acid (FFA) profile.

METHODS

Twenty-five SSc patients with ACA or anti-Scl70 autoantibodies were enrolled. The microbiota of faecal, saliva and superficial epidermal samples was assessed through next-generation sequencing analysis. GC-MS was used to quantify faecal and serum FFAs. Gastrointestinal symptoms were investigated with the University of California Los Angeles Scleroderma Clinical Trial Consortium Gastrointestinal Tract Instrument (UCLA GIT-2.0) questionnaire.

RESULTS

The ACA+ and anti-Scl70+ groups displayed different cutaneous and faecal microbiota profiles. The classes of cutaneous Sphingobacteriia and Alphaproteobacteria, the faecal phylum Lentisphaerae, the levels of the classes Lentisphaeria and Opitutae, and the genus NA-Acidaminococcaceae were significantly higher in faecal samples from the ACA+ patients than in samples from the anti-Scl70+ patients. The cutaneous Sphingobacteria and the faecal Lentisphaerae were significantly correlated (rho = 0.42; P = 0.03). A significant increase in faecal propionic acid was observed in ACA+ patients. Moreover, all levels of faecal medium-chain FFAs and hexanoic acids were significantly higher in the ACA+ group than in the anti-Scl70+ group (P < 0.05 and P < 0.001, respectively). In the ACA+ group, the analysis of the serum FFA levels showed an increasing trend in valeric acid.

CONCLUSION

Different microbiota signatures and FFA profiles were found for the two groups of patients. Despite being in different body districts, the cutaneous Sphingobacteria and faecal Lentisphaerae appear interdependent.

Dietary monoglyceride supplementation to support intestinal integrity and host defenses in health-challenged weanling pigs

Frequent incidence of postweaning enterotoxigenic Escherichia coli (ETEC) diarrhea in the swine industry contributes to high mortality rates and associated economic losses. In this study, a combination of butyric, caprylic, and capric fatty acid monoglycerides was investigated to promote intestinal integrity and host defenses in weanling pigs infected with ETEC. A total of 160 pigs were allotted to treatment groups based on weight and sex. Throughout the 17-d study, three treatment groups were maintained: sham-inoculated pigs fed a control diet (uninfected control [UC], n = 40), ETEC-inoculated pigs fed the same control diet (infected control [IC], n = 60), and ETEC-inoculated pigs fed the control diet supplemented with monoglycerides included at 0.3% of the diet (infected supplemented [MG], n = 60). After a 7-d acclimation period, pigs were orally inoculated on each of three consecutive days with either 3 mL of a sham-control (saline) or live ETEC culture (3 × 109 colony-forming units/mL). The first day of inoculations was designated as 0 d postinoculation (DPI), and all study outcomes reference this time point. Fecal, tissue, and blood samples were collected from 48 individual pigs (UC, n = 12; IC, n = 18; MG, n = 18) on 5 and 10 DPI for analysis of dry matter (DM), bacterial enumeration, inflammatory markers, and intestinal permeability. ETEC-inoculated pigs in both the IC and MG groups exhibited clear signs of infection including lower (P < 0.05) gain:feed and fecal DM, indicative of excess water in the feces, and elevated (P < 0.05) rectal temperatures, total bacteria, total E. coli, and total F18 ETEC during the peak-infection period (5 DPI). Reduced (P < 0.05) expression of the occludin, tumor necrosis factor α, and vascular endothelial growth factor A genes was observed in both ETEC-inoculated groups at the 5 DPI time point. There were no meaningful differences between treatments for any of the outcomes measured at 10 DPI. Overall, all significant changes were the result of the ETEC infection, not monoglyceride supplementation.

Membrane-Disruptive Effects of Fatty Acid and Monoglyceride Mitigants on E. coli Bacteria-Derived Tethered Lipid Bilayers

We report electrochemical impedance spectroscopy measurements to characterize the membrane-disruptive properties of medium-chain fatty acid and monoglyceride mitigants interacting with tethered bilayer lipid membrane (tBLM) platforms composed of E. coli bacterial lipid extracts. The tested mitigants included capric acid (CA) and monocaprin (MC) with 10-carbon long hydrocarbon chains, and lauric acid (LA) and glycerol monolaurate (GML) with 12-carbon long hydrocarbon chains. All four mitigants disrupted E. coli tBLM platforms above their respective critical micelle concentration (CMC) values; however, there were marked differences in the extent of membrane disruption. In general, CA and MC caused larger changes in ionic permeability and structural damage, whereas the membrane-disruptive effects of LA and GML were appreciably smaller. Importantly, the distinct magnitudes of permeability changes agreed well with the known antibacterial activity levels of the different mitigants against E. coli, whereby CA and MC are inhibitory and LA and GML are non-inhibitory. Mechanistic insights obtained from the EIS data help to rationalize why CA and MC are more effective than LA and GML at disrupting E. coli membranes, and these measurement capabilities support the potential of utilizing bacterial lipid-derived tethered lipid bilayers for predictive assessment of antibacterial drug candidates and mitigants.

DHA and EPA inhibit porcine coronavirus replication by alleviating ER stress

IMPORTANCE

Porcine epidemic diarrhea caused by porcine coronaviruses remains a major threat to the global swine industry. Fatty acids are extensively involved in the whole life of the virus. In this study, we found that docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) significantly reduced the viral load of porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), and porcine delta coronavirus (PDCoV) and acted on the replication of the viruses rather than attachment and entry. We further confirmed that DHA and EPA inhibited PEDV replication by alleviating the endoplasmic reticulum stress. Meanwhile, DHA and EPA alleviate PEDV-induced inflammation and reactive oxygen species (ROS) levels and enhance the cellular antioxidant capacity. These data indicate that DHA and EPA have antiviral effects on porcine coronaviruses and provide a molecular basis for the development of new fatty acid-based therapies to control porcine coronavirus infection and transmission.

Tricaprylin, a medium-chain triglyceride, aggravates high-fat diet-induced fat deposition but improves intestinal health

Medium-chain triglycerides (MCTs) are absorbed and metabolized more rapidly than long-chain triglycerides (LCTs) and therefore are considered to have obesity-prevention potential in foods. The effect of adding tricaprylin, an MCT, to food on fat deposition and intestinal health is uncharted. In this study, mice were randomly divided into four groups and fed a normal diet (ND), ND with tricaprylin, a high-fat diet (HFD), or HFD with tricaprylin. Supplementation of 2% tricaprylin in HFD significantly increased the body weight, fat mass, liver weight, adipocyte size in adipose tissue and liver, and upregulated genes related to fat deposition. Metabolomic analysis of serum and adipose tissue revealed that tricaprylin significantly increased the contents of metabolites related to lipid metabolism, triglyceride storage, and fat deposition related signaling pathways. In vitro experiments and molecular docking analysis suggest that octanoic acid, a primary decomposition product of tricaprylin, may promote adipogenic differentiation of preadipocytes by acting as a PPARγ ligand to activate the expression of lipogenesis-related genes. Although supplementation with 2% tricaprylin in HFD cannot reduce fat deposition, it has a beneficial effect on intestinal health. Tricaprylin improved intestinal morphology, digestive enzyme activity, short-chain fatty acid concentration, and intestinal barrier function-related protein expression, while reducing inflammatory factor levels and the abundance of harmful intestinal microorganisms.

Glycerol Monolaurate Inhibits Wild-Type African Swine Fever Virus Infection in Porcine Macrophages

Naturally abundant antimicrobial lipids, such as fatty acids and monoglycerides, that disrupt membrane-enveloped viruses are promising mitigants to inhibit African swine fever virus (ASFV). Among mitigant candidates in this class, glycerol monolaurate (GML) has demonstrated particularly high antiviral activity against laboratory-adapted ASFV strains. However, there is an outstanding need to further determine the effects of GML on wild-type ASFV strains, which can have different virulence levels and sensitivities to membrane-disrupting compounds as compared to laboratory-adapted strains. Herein, we investigated the antiviral effects of GML on a highly virulent strain of a wild-type ASFV isolate (Armenia/07) in an in vitro porcine macrophage model. GML treatment caused a concentration-dependent reduction in viral infectivity, and there was a sharp transition between inactive and active GML concentrations. Low GML concentrations had negligible effect on viral infectivity, whereas sufficiently high GML concentrations caused a >99% decrease in viral infectivity. The concentration onset of antiviral activity matched the critical micelle concentration (CMC) value of GML, reinforcing that GML micelles play a critical role in enabling anti-ASFV activity. These findings validate that GML can potently inhibit wild-type ASFV infection of porcine macrophages and support a biophysical explanation to guide antimicrobial lipid performance optimization for pathogen mitigation applications.

Isolation of porcine reproductive and respiratory syndrome virus from feed ingredients and complete feed, with subsequent RT-qPCR analysis

We used virus isolation (VI) to determine tissue culture infectivity and reverse-transcription quantitative PCR (RT-qPCR) to determine the stability of porcine reproductive and respiratory syndrome virus 2 (PRRSV) strain P129 in solvent-extracted soybean meal (SBM), dried distillers grains with solubles (DDGS), complete swine feed (FEED), or medium (DMEM) at 4°C, 23°C, or 37°C for up to 3 d. Samples of each treatment were taken at regular intervals and processed. Supernatant was titrated and used to inoculate confluent MARC-145 cells to determine infectivity. RNA was extracted from each supernatant sample and tested by RT-qPCR to determine any change in detectable virus RNA across matrix type, temperature, and time. An interaction (p = 0.028) was observed for matrix × temperature × hour for live virus detected by VI. At 4°C, the concentration of infectious virus was greatest in DMEM, intermediate in SBM, and lowest in DDGS and FEED. DMEM also had the greatest concentration of infectious PRRSV at 23°C over time; a higher infectious virus concentration was maintained in SBM for longer than in DDGS or FEED. At 37°C, a greater concentration of infectious virus was sustained in DMEM than in the feedstuffs, with concentrations decreasing until 48 h post-inoculation. Only matrix type influenced the quantity of viral RNA detected by RT-qPCR (p = 0.032). More viral RNA was detected in the virus control than in DDGS; SBM and FEED were intermediate. By VI, we found that infectious virus could be harbored in SBM, DDGS, and FEED for a short time.

Evaluation of dynamic effects of dietary medium-chain monoglycerides on performance, intestinal development and gut microbiota of broilers in large-scale production

Medium-chain monoglycerides (MG) have been reported to affect the productive performance, gut microbiota and health of broiler chickens reared in ideal experimental conditions at home and abroad. However, the effects of MG on performance, intestinal development and gut microbiota of chickens in large-scale farms during different feed stages remain unknown. The present study was conducted on a modern farm with a total of 12,000 yellow feathered broiler chicks that were randomly allotted to 2 groups (1000 chicks/replicate, 6 replicates/group) for a 70-day trial. The control group (CON group) received a basal diet, and the treated group (MG group) was fed a basal diet containing 300 mg/kg mixed MG. The results revealed that dietary MG significantly (P < 0.05) increased the body weight and average feed intake, but notably reduced the feed conversion and mortality of chickens in large-scale production during the starter phase. The villus height of the duodenum in the MG group at 1, 2 and 7 wk of age increased notably, and the villus height to crypt depth ratio at 1, 2, 5 and 10 wk of age was improved. Dietary MG decreased the serum insulin content of chickens at 5, 7 and 10 wk of age, and decreased the serum lipopolysaccharide at 3 and 7 wk of age. The triglyceride level of chickens at 3, 5 and 10 wk of age and the low-density lipoprotein cholesterol level of chickens at 7 and 10 wk of age in the MG group decreased notably, while the high-density lipoprotein cholesterol increased significantly. Moreover, MG supplementation selectively increased the relative abundance of genus Bacteroides (family Bacteroidaceae) and Lachnospiraceae_NK4A136_group, but decreased the content of genus Rikenellaceae_RC9_gut_group, Collinsella and family Barnesiellaceae in the cecum of chickens at 3, 7 and 10 wk of age. Conclusively, these findings showed that dietary MG notably enhanced chicken performance, health and feed nutrient utilization at early ages by regulating gut microbiota, intestinal development and serum biochemical indices.

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.

Food additive glycerol monocaprylate modulated systemic inflammation and gut microbiota without stimulating metabolic dysfunction in high-fat diet fed mice

Recent findings imply that great consideration should be given to the potential health risks of food additives on gut microbiota. Glycerol monocaprylate (GMC) is a widely consumed food preservative and emulsifier. Our results indicated that GMC significantly ameliorated visceral fat accumulation and systemic inflammation in high-fat diet (HFD)-fed mice. Furthermore, GMC induced improvements on the composition and function of gut microbiota, resulting in increased beneficial gut bacteria (Bifidobacterium and Lactobacillus) and promoted production of short chain fatty acids. Notably, GMC-induced metabolic amelioration is closely related to the regulation in gut microbiota. Overall, our findings supported that unlike the emulsifiers previously reported to damage intestinal health, GMC performed the potential on attenuating HFD-induced metabolic disorders and gut microbiota dysbiosis, which also refined on the safety evaluation of GMC on gut microbiota. Our findings suggest that when evaluating the safety of food additives with regards to gut microbiota, it is important to take into account the specific characteristics of the additive in question, rather than simply relying on its classification.

Maternal supplementation with glycerol monolaurate improves the intestinal health of suckling piglets by inhibiting the NF-κB/MAPK pathways and improving oxidative stability

Glycerol monolaurate (GML) is a food safe emulsifier and a kind of MCFA monoglyceride that has been proven to confer positive benefits in improving animal health, production and feed digestibility as a feed additive. This study aims to evaluate whether supplementation of a sow diet with GML could affect the intestinal barrier function and antioxidant status of newborn piglets and to explore its regulatory mechanism. A total of 80 multiparous sows were divided into two groups, which were fed a basal diet or a basal diet supplemented with 0.1% GML. The results indicated that maternal supplementation with GML significantly increased fat, lactose and protein in sow colostrum, as well as fat and protein in sow 14-day milk (P < 0.05). The results showed that GML significantly reduced the concentrations of IL-12 in the duodenum, TNF-α, IL-1β and IL-12 in the jejunum, and IL-1β in the ileum of piglets (P < 0.05). Higher concentrations of T-AOC, T-SOD, GSH and GSH-Px and lower MDA in the intestine were observed in the GML group than in the control group. Correspondingly, the villi height, crypt depth and the ratio of villi height to crypt depth (V/C) in the jejunum and the V/C in the ileum in the GML group were significantly higher than those in the control group (P < 0.05). Moreover, the GML group displayed significantly increased protein abundance of zonula occludens (ZO)-1, occludin, and claudin-1 in the small intestine (P < 0.05), mRNA expression of mucins (MUCs) in the small intestine (MUC-1, MUC-3 and MUC-4), and mRNA expression of porcine beta defensins (pBDs) in the duodenum (pBD1 and pBD2), jejunum (pBD1, pBD2 and pBD129) (P < 0.05), and ileum (pBD2, pBD3 and pBD114) (P < 0.05). Further research showed that GML significantly reduced the phosphorylation of the NF-κB/MAPK pathways in the small intestine (P < 0.05). In addition, the results of 16S rDNA sequencing showed that maternal supplementation with GML altered the colonic microbiotic structure of piglets, and reduced the relative abundance of Escherichia shigella. In summary, a sow diet supplemented with GML enhanced the offspring's intestinal oxidative stability and barrier function and attenuated the offspring's intestinal inflammatory response, possibly by suppressing the activation of the NF-κB/MAPK pathways.

Effects of Different Combinations of Sodium Butyrate, Medium-Chain Fatty Acids and Omega-3 Polyunsaturated Fatty Acids on the Reproductive Performance of Sows and Biochemical Parameters, Oxidative Status and Intestinal Health of Their Offspring

The aim of the study was to investigate the comparative effects of different combinations of sodium butyrate (SB), medium-chain fatty acids (MCFAs), and omega-3 polyunsaturated fatty acids (n-3 PUFAs) on the reproductive performances of sows, as well as on the biochemical parameters, oxidative statuses, and intestinal health of the sucking piglets. A total of 30 sows were randomly allocated to five treatments: (1) control diet (CON); (2) CON with 1 g/kg of coated SB and 7.75 g/kg of coated MCFAs (SM); (3) CON with 1 g/kg of coated SB and 68.2 g/kg of coated n-3 PUFAs (SP); (4) CON with 7.75 g/kg of coated MCFAs and 68.2 g/kg of coated n-3 PUFAs (MP); (5) CON with 1 g/kg of coated SB, 7.75 g/kg of coated MCFAs and 68.2 g/kg of coated n-3 PUFA (SMP). The results showed that sows fed the SP, MP, and SMP diets had shorter weaning-to-estrus intervals than those fed the CON diet (p < 0.01). The piglets in the SM, SP, and MP groups showed higher increases in the plasma catalase and glutathione peroxidase activities than those of the CON group (p < 0.01). The diarrhea incidence of piglets in the SM, SP and SMP groups was lower than that of piglets in the CON group (p < 0.01). Additionally, the addition of SM, SP, MP, and SMP to the sow diets increased the contents of immunoglobulin A, immunoglobulin G, fat, and proteins in the colostrum (p < 0.01), as well as the plasma total superoxide dismutase activities (p < 0.01) in the suckling piglets, whereas it decreased the mRNA expressions of tumor necrosis factor-α, interleukin-1β, and toll-like receptor 4 in the jejunum mucosa of the piglets. The relative abundances of Prevotella, Coprococcus, and Blautia in the colonic digesta of the piglets were increased in the SM group (p < 0.05), and the relative abundances of Faecalibacterium increased in the SMP group (p < 0.05), compared with the CON group. The relative abundances of Collinsella, Blautia, and Bulleidia in the MP group were higher than those in the CON group (p < 0.05). Collectively, dietary combinations of fatty acids with different chain lengths have positive effects on the growth performances and intestinal health of suckling piglets.

Medium chain fatty acid supplementation improves animal metabolic and immune status during the transition period: A study on dairy cattle

The transition period is the stage of the high incidence of metabolic and infectious diseases in dairy cows. Improving transition dairy cows' health is crucial for the industry. This study aimed to determine the effects of dietary supplementation medium-chain fatty acids (MCFAs) on immune function, metabolic status, performance of transition dairy cows. Twenty multiparous Holstein cows randomly assigned to two treatments at 35 d before calving. 1) CON (fed the basal 2) MCFA treatment (basal diet was supplemented at an additional 20 g MCFAs mixture every day) until 70 d after calving. The results showed that the serum amyloid A myeloperoxidase concentrations in the blood of cows in MCFA treatment significantly decreased during the early lactation (from 1 d to 28 d after calving) 0.03, 0.04, respectively) compared with the CON, while the tumor necrosis factor concentration was significantly decreased at 56 d after calving (P = 0.02). In addition, the concentration of insulin in the pre-calving (from 21 d before calving to calving) blood of cows in MCFA treatment was significantly decreased (P = 0.04), and concentration of triglyceride also showed a downward trend at 28 d after calving 0.07). Meanwhile, MCFAs supplementation significantly decreased the concentrations of lithocholic acid, hyodeoxycholic acid, and hyocholic acid in the blood at 1 d calving (P = 0.02, < 0.01, < 0.01, respectively), and the level of hyocholic acid taurocholic acid concentrations (P < 0.01, = 0.01, respectively) decreased dramatically at 14 d after calving. However, compared with the CON, the pre-calving dry matter intake and the early lactation milk yield in MCFA treatment were significantly decreased (P = 0.05, 0.02, respectively). In conclusion, MCFAs supplementation transition diet could improve the immune function and metabolic status of dairy cows, and the health of transition cows might be beneficial from the endocrine status.

In vitro and in vivo antiviral activity of monolaurin against Seneca Valley virus

Introduction

Surveillance of the Seneca Valley virus (SVV) shows a disproportionately higher incidence on Chinese pig farms. Currently, there are no vaccines or drugs to treat SVV infection effectively and effective treatment options are urgently needed.

Methods

In this study, we evaluated the antiviral activity of the following medium-chain fatty acids (MCFAs) or triglycerides (MCTs) against SVV: caprylic acid, caprylic monoglyceride, capric monoglyceride, and monolaurin.

Results

In vitro experiments showed that monolaurin inhibited viral replication by up to 80%, while in vivo studies showed that monolaurin reduced clinical manifestations, viral load, and organ damage in SVV-infected piglets. Monolaurin significantly reduced the release of inflammatory cytokines and promoted the release of interferon-γ, which enhanced the viral clearance activity of this type of MCFA.

Discussion

Therefore, monolaurin is a potentially effective candidate for the treatment of SVV infection in pigs.

Dietary supplementation with full-fat Hermetia illucens larvae and multi-probiotics, as a substitute for antibiotics, improves the growth performance, gut health, and antioxidative capacity of weaned pigs

BACKGROUND

Dietary supplementation of full-fat black soldier fly larvae (BSFL full-fat meal; alone or in combination with multi-probiotics) was tested as an alternative to dietary antibiotics in weaning piglets. We also tested the effects of these diets on growth performance, nutrient digestibility coefficients, immune status, oxidative stress, intestinal histomorphology, and rectal microbial modulations in weaned pigs. A total of 80 piglets [(Landrace × Large White) × Duroc] of both sexes (a ratio of gilts and barrows; 1:1), were randomly allotted to four diet groups: positive control (PC) diet supplemented with 0.02% amoxicillin; negative control (NC) diet without supplement addition; BSFL12 diet (NC + 12% BSFL full-fat meal); and BSFL + Pro diet (BSFL full-fat meal + 0.1% multi-probiotics, including Bacillus subtilis, B. licheniformis, and Saccharomyces cerevisiae). All groups had five replicates, with four piglets per replicate.

RESULTS

Dietary BSFL + Pro improved the overall average daily gain (P = 0.013), and gain-to-feed ratio (P = 0.032). The BSFL12 and BSFL + Pro diets improved nutrient digestibility and increased the serum levels of immunoglobulin A and glutathione peroxidase, while reducing the levels of pro-inflammatory cytokines. The spleen weight was higher and caecal pH was lower in pigs fed the BSFL + Pro diet than in those fed the NC diet (P = 0.011 and P = 0.021, respectively). Pigs fed the BSFL diets had longer duodenal villi, a higher villus height-to-crypt depth ratio (P = 0.004), and shorter crypt depth (P = 0.017) than those fed NC. The BSFL + Pro diet also increased faecal Lactobacillus spp. count (P = 0.008) and reduced Escherichia coli (P = 0.021) counts compared with that seen with PC and NC diets, respectively.

CONCLUSIONS

Dietary supplementation with BSFL or BSFL + multi-probiotics can improve the growth performance and intestinal health of pigs and may be an effective strategy to replace antibiotics for weaned pigs.

In vitro investigation of monoglycerides and zinc glycinate: anti-inflammatory and epithelial barrier function

The objectives of this study were to investigate the in vitro immune-modulatory effects of monoglycerides and zinc glycinate with porcine alveolar macrophages (PAM) and their impact on epithelial barrier integrity using the intestinal porcine enterocyte cell line (IPEC-J2). Cell viability was assessed using a Vybrant MTT assay to determine the appropriate dose range of monoglyceride blend (C4, C8, and C10) and zinc glycinate. In experiment 1, IPEC-J2 cells (5 × 105 cells/mL) were seeded and treated with each compound (monoglycerides: 0, 25, 100, 250, 500, and 1,000 µg/mL; zinc glycinate: 0, 2, 5, 12.5, 25, and 50 µg/mL). Transepithelial electrical resistance (TEER) was measured by Ohm's law method at 0 h (before treatment) and at 24, 48, and 72 h posttreatment. In experiment 2, PAM were collected from 6 clinically healthy piglets (7 wk of age) and seeded at 106 cells/mL. After incubation, the cells were treated with each compound and/or lipopolysaccharide (LPS). The experimental design was a 2 × 6 factorial arrangement with 2 doses of LPS (0 or 1 μg/mL) and 6 doses of each compound (monoglycerides: 0, 50, 100, 250, 500, and 1,000 µg/mL; zinc glycinate: 0, 25, 50, 100, 250, and 500 µg/mL). Cell supernatants were collected to analyze the concentrations of tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β) by enzyme-linked immunosorbent assay kits. Data were analyzed by ANOVA using PROC MIXED of SAS with a randomized complete block design. IPEC-J2 cells treated with 250 or 1,000 μg/mL of monoglycerides, or 5 μg/mL of zinc glycinate had increased (P < 0.05) TEER values at 48 or 72 h posttreatment, compared with control. The LPS challenge increased (P < 0.05) the production of TNF-α and IL-1β from PAM. In the non-challenge group, 50 or 100 μg/mL of monoglycerides stimulated (P < 0.05) TNF-α and IL-1β production from PAMs. Treatment with 25 or 100 μg/mL of zinc glycinate also enhanced (P < 0.05) TNF-α production from PAM. In LPS-treated PAM, 1,000 μg/mL of monoglycerides increased (P < 0.05) IL-1β production, while zinc glycinate suppressed (P < 0.0001) the secretion of TNF-α and IL-1β at the doses of 100, 250, and 500 μg/mL. In conclusion, the results of this in vitro study indicate that monoglycerides positively affect the barrier function of the epithelium, while zinc glycinate may have strong immune regulatory benefits. Future animal studies will be required to verify their impacts on animal gut health, systemic immunity, and growth performance.

Protective effect of phytogenic plus short and medium-chain fatty acids-based additives in enterotoxigenic Escherichia coli challenged piglets

Post Weaning Diarrhea (PWD) is the most important multifactorial gastroenteric disease of the weaning in pig livestock. Phytogenic (PHY) natural extracts are largely studied as alternatives to antibiotic treatments in combating the global concern of the antimicrobial resistance. The aim of this study was to evaluate the protective effect of innovative phytogenic premix with or without short and medium chain fatty acids (SCFA and MCFA) in O138 Escherichia coli challenged piglets. Twenty-seven weaned piglets were allotted into four groups fed different diets according to the following dietary treatments: CTRL (n = 13) group fed basal diet, PHY1 (n = 7) fed the basal diet supplemented with 0.2% of phytogenic premix, PHY2 (n = 7) fed the basal diet supplemented with 0.2% of phytogenic premix added with 2000 ppm of SCFA and MCFA. After 6 days of experimental diet feeding, animals were challenged (day 0) with 2 × 10⁹ CFU of E. coli and CTRL group was divided at day 0 into positive (challenged CTRL + ; n = 6) and negative control group (unchallenged CTRL-; n = 7). Body weights were recorded at -14, -6, 0, 4 and 7 days and the feed intake was recorded daily. E. coli shedding was monitored for 4 days post-challenge by plate counting. Fecal consistency was registered daily by a four-point scale (0-3; diarrhea > 1) during the post-challenge period. Tissue samples were obtained for gene expression and histological evaluations at day 7 from four animals per group. Lower average feed intake was observed in CTRL + compared to PHY2 and CTRL during the post-challenge period. Infected groups showed higher E. coli shedding compared to CTRL- during the 4 days post-challenge (p < 0.01). PHY2 showed lower frequency of diarrhea compared to PHY1 and CTRL + from 5 to 7 days post-challenge. No significant alterations among groups were observed in histopathological evaluation. Duodenum expression of occludin tended to be lower in challenged groups compared to CTRL- at 7 days post-challenge (p = 0.066). In conclusion, dietary supplementation of PHY plus SCFA and MCFA revealed encouraging results for diarrhea prevention and growth performance in weaned piglets.

Improvements in Performance of Nursery Pigs Provided with Supplemental Oil Derived from Black Soldier Fly (Hermetia illucens) Larvae

The current study evaluated the impact of increasing levels of supplemental black soldier fly larvae (BSFL) oil, a novel and sustainable feed ingredient, on growth performance and blood chemistry indices in nursery pigs. Pigs were weaned at 21 days of age (n = 192; body weight = 6.9 ± 0.15 kg) and randomly allotted within sex and body weight to 1 of 4 dietary treatments, using 48 pens (4 pigs/pen). Treatments contained 0, 2, 4, or 6% supplemental BSFL oil, replacing equivalent quantities of corn oil. A 3-phase feeding program was used with 14, 11, and 15 days for phase 1 to 3, respectively. Supplementation of BSFL oil linearly (p ≤ 0.052) improved pig body weight and daily gain throughout the study and overall. No differences were observed in feed intake; however, feed efficiency was linearly improved with BSFL oil supplementation for phase 1 and 2 (p < 0.05). Serum cholesterol increased linearly (p = 0.002) and platelet count tended to increase linearly (p = 0.082) with increasing BSFL oil. No other differences were detected in blood chemistry and all results were within normal ranges. In conclusion, BSFL oil is a valuable, energy-dense feed ingredient that can promote growth performance of nursery pigs.

Ca:Mg ratio, medium-chain fatty acids, and the gut microbiome

BACKGROUND & AIMS

Ketogenic medium-chain fatty acids (MCFAs) with profound health benefits are commonly found in dairy products, palm kernel oil and coconut oil. We hypothesize that magnesium (Mg) supplementation leads to enhanced gut microbial production of MCFAs and, in turn, increased circulating MCFAs levels.

METHODS

We tested this hypothesis in the Personalized Prevention of Colorectal Cancer Trial (PPCCT) (NCT01105169), a double-blind 2 × 2 factorial randomized controlled trial enrolling 240 participants. Six 24-h dietary recalls were performed for all participants at the baseline and during the intervention period. Based on the baseline 24-h dietary recalls, the Mg treatment used a personalized dose of Mg supplementation that would reduce the calcium (Ca): Mg intake ratio to around 2.3. We measured plasma MCFAs, sugars, ketone bodies and tricarboxylic acid cycle (TCA cycle) metabolites using the Metabolon's global Precision Metabolomics™ LC-MS platform. Whole-genome shotgun metagenomics (WGS) sequencing was performed to assess microbiota in stool samples, rectal swabs, and rectal biopsies.

RESULTS

Personalized Mg treatment (mean dose 205.58 mg/day with a range from 77.25 to 389.55 mg/day) significantly increased the plasma levels of C7:0, C8:0, and combined C7:0 and C8:0 by 18.45%, 25.28%, and 24.20%, respectively, compared to 14.15%, 10.12%, and 12.62% decreases in the placebo arm. The effects remain significant after adjusting for age, sex, race and baseline level (P = 0.0126, P = 0.0162, and P = 0.0031, respectively) and FDR correction at 0.05 (q = 0.0324 for both C7:0 and C8:0). Mg treatment significantly reduced the plasma level of sucrose compared to the placebo arm (P = 0.0036 for multivariable-adjusted and P = 0.0216 for additional FDR correction model) whereas alterations in daily intakes of sucrose, fructose, glucose, maltose and C8:0 from baseline to the end of trial did not differ between two arms. Mediation analysis showed that combined C7:0 and C8:0 partially mediated the effects of Mg treatment on total and individual ketone bodies (P for indirect effect = 0.0045, 0.0043, and 0.03, respectively). The changes in plasma levels of C7:0 and C8:0 were significantly and positively correlated with the alterations in stool microbiome α diversity (r = 0.51, p = 0.0023 and r = 0.34, p = 0.0497, respectively) as well as in stool abundance for the signatures of MCFAs-related microbiota with acyl-ACP thioesterase gene producing C7:0 (r = 0.46, p = 0.0067) and C8:0 (r = 0.49, p = 0.003), respectively, following Mg treatment.

CONCLUSIONS

Optimizing Ca:Mg intake ratios to around 2.3 through 12-week personalized Mg supplementation leads to increased circulating levels of MCFAs (i.e. C7:0 and C8:0), which is attributed to enhanced production from gut microbial fermentation and, maybe, sucrose consumption.

Antimicrobial monoglycerides for swine and poultry applications

The development of natural, broadly acting antimicrobial solutions to combat viral and bacterial pathogens is a high priority for the livestock industry. Herein, we cover the latest progress in utilizing lipid-based monoglycerides as feed additives to address some of the biggest challenges in animal agriculture. The current industry needs for effective antimicrobial strategies are introduced before discussing why medium-chain monoglycerides are a promising solution due to attractive molecular features and biological functions. We then critically analyze recent application examples in which case monoglycerides demonstrated superior activity to prevent feed transmission of viruses in swine and to mitigate bacterial infections in poultry along with gut microbiome modulation capabilities. Future innovation strategies are also suggested to expand the range of application possibilities and to enable new monoglyceride delivery options.

Effects of formic acid and glycerol monolaurate on weanling pig growth performance, fecal consistency, fecal microbiota, and serum immunity

A total of 350 weanling pigs (DNA 400 × 200; initially, 5.67 ± 0.06 kg BW) were used in a 42-day study with 5 pigs per pen and 14 replicate pens per treatment. At weaning, pigs were allotted to pens in a completely randomized design and pens of pigs were randomly assigned to one of five dietary treatments: 1) negative control (CON; standard nursery diet containing only 150 ppm Zn from trace mineral premix and no acidifier); 2) control diet with 3,000 ppm added zinc from ZnO included in phase 1 and 2,000 ppm added zinc from ZnO included in phase 2 (ZnO); 3) control diet with 0.70% formic acid (FA; Amasil NA; BASF, Florham, NJ); 4) control diet with 0.18% glycerol monolaurate (GML; Natural Biologics GML, Natural Biologics, Newfield, NY); and 5) control diet with a 1.0% blend of formic acid and glycerol monolaurate (FORMI; FORMI 3G, ADDCON GmbH, Bitterfeld-Wolfen, Germany). Pigs were fed treatment diets from d 0 to d 28 and were then fed a common diet from d 28 to d 42. From days 0 to 7, pigs fed ZnO or FORMI had increased (P = 0.03) ADG compared to pigs fed CON, with no difference in feed intake (P > 0.05). Overall, pigs fed GML had reduced (P < 0.0001) ADG compared with those fed the CON, ZnO, or FORMI diets. Fecal DM was evaluated from days 7 to 28 and there was a treatment × day interaction (P = 0.04). Pigs fed GML had a lower fecal DM % on day 7, but a higher fecal DM % on days 14 and 21; however, no differences in fecal DM were observed on day 28. Fresh fecal samples were collected from the same randomly selected pig on days 0 and 14 (70 pigs total;14 pigs per treatment) for analysis of fecal microbial populations using 16S rDNA sequencing. Dietary treatment did not significantly impact fecal microbiota at the phyla level, but pigs fed ZnO had an increased relative abundance (P < 0.01) of the family Clostridiaceae. A blood sample was also collected from one pig per pen on days 0 and 14 for analysis of serum IgA, IgG, and TNF-α. There was no evidence that dietary treatment effected IgA, IgG, or TNF-α concentrations. The effect of sampling day was significant (P < 0.05), where circulating IgA and TNF-α was increased and IgG was decreased from days 0 to 14. In summary, there is potential for a blend of formic acid and GML to improve growth performance immediately post-weaning without negatively impacting fecal consistency. Formic acid and GML alone or in combination did not impact fecal microbial populations or serum immune parameters.

From Farm to Fork: Streptococcus suis as a Model for the Development of Novel Phage-Based Biocontrol Agents

Bacterial infections of livestock threaten the sustainability of agriculture and public health through production losses and contamination of food products. While prophylactic and therapeutic application of antibiotics has been successful in managing such infections, the evolution and spread of antibiotic-resistant strains along the food chain and in the environment necessitates the development of alternative or adjunct preventive and/or therapeutic strategies. Additionally, the growing consumer preference for "greener" antibiotic-free food products has reinforced the need for novel and safer approaches to controlling bacterial infections. The use of bacteriophages (phages), which can target and kill bacteria, are increasingly considered as a suitable measure to reduce bacterial infections and contamination in the food industry. This review primarily elaborates on the recent veterinary applications of phages and discusses their merits and limitations. Furthermore, using Streptococcus suis as a model, we describe the prevalence of prophages and the anti-viral defence arsenal in the genome of the pathogen as a means to define the genetic building blocks that are available for the (synthetic) development of phage-based treatments. The data and approach described herein may provide a framework for the development of therapeutics against an array of bacterial pathogens.

Simultaneous medium chain fatty acids production and process carbon emissions reduction in a continuous-flow reactor: Re-understanding of carbon flow distribution

Due to its wide application and high value, the production of medium chain fatty acids (MCFAs) from waste biomass has become one of the worldwide research hotspots. Increasing the carbon element participation from short-chain fatty acids to the form of MCFAs is also conductive to reduce the release of biogas from biological treatment process, because carbon is in the form of MCFAs instead of biogas which directly contribute to process carbon emissions reduction. However, many barriers limiting MCFAs production and application remain to be resolved. Aiming continuous MCFAs production from lactate-rich waste biomass, this study optimized the operation conditions and clarified the main limiting factors and possible mechanisms. The maximum caproic acid concentration of 2.757 g/L were obtained at the Upflow Velocity (ULV) of 1.15 m/h and pH 4.9-5.1. Caproiciproducens, Pseudoramibacter, norank_f_Eubacteriaceae, and Oscillibacter were identified to be the dominant microbial genus responsible for MCFAs production from lactate. The reduction of carbon emissions calculation was also studied in the present processes.