Background Weaning-induced diarrhoea and growth retardation in piglets are associated with impaired intestinal barrier function and decreased levels of colonic short-chain fatty acids(SCFAs).Although SCFA supplementat...Background Weaning-induced diarrhoea and growth retardation in piglets are associated with impaired intestinal barrier function and decreased levels of colonic short-chain fatty acids(SCFAs).Although SCFA supplementation has been proposed to mitigate these issues,the efficacy and optimal dosage of sodium isobutyrate remain unclear.Results We investigated the effects of sodium isobutyrate supplementation(500,1,000,2,000,and 4,000 mg/kg diet)on weaned piglets(Duroc×Landrace×Yorkshire,28 d of age;n=8).After a 28-d feeding trial,supplementation at 500–2,000 mg/kg significantly improved average daily gain and feed efficiency and reduced diarrhoea frequency,with maximal benefits observed at 1,000 mg/kg(P<0.0001).Additionally,500–1,000 mg/kg sodium isobutyrate supplementation increased the apparent digestibility of crude protein,organic matter,and crude fibre(P<0.05).Serum biochemical parameters were unaffected,although secretory immunoglobulin A(SIgA)levels significantly increased upon supplementation with 500–1,000 mg/kg(P<0.05).16S rRNA gene sequencing indicated that sodium isobutyrate increased the abundance of beneficial colonic microbiota.The 1,000 mg/kg group presented the most pronounced effect,with a significant increase of the relative abundance of Prevotella and the greatest improvement in SCFA concentrations(P<0.05).Metabolomics revealed elevated levels of colonic indole-3-lactic acid and 3-hydroxybutyrate upon supplementation with 1,000 mg/kg(P<0.05).Transcriptomic analyses indicated activation of protein digestion and absorption pathways,and PI3K-Akt signalling,marked by TSG-6 upregulation and the suppression of ISG15 and DDIT4 expression(P<0.05).Supplementation with 1,000 mg/kg was associated with improved intestinal barrier-related markers,including reduced serum D-lactate,diamine oxidase,and lipopolysaccharide levels,increased tight junction protein expression;activation of G protein-coupled receptors;and inhibition of TLR4/MyD88/NF-κB signalling(P<0.05),suggesting enhanced barrier function.Conclusions In conclusion,dietary supplementation with 1,000 mg/kg sodium isobutyrate was associated with improved intestinal morphology,reduced serum permeability,increased expression of tight junction proteins,and enhanced immune function in weaned piglets,suggesting enhanced colonic barrier function and providing dosage guidance and mechanistic insights for future applications.展开更多
Background Isoacids are the product of branched-chain amino acid fermentation and are naturally producedin the hindgut by microbial fermentation. In ruminants, supplementation of isoacids as a feed additive improvesfi...Background Isoacids are the product of branched-chain amino acid fermentation and are naturally producedin the hindgut by microbial fermentation. In ruminants, supplementation of isoacids as a feed additive improvesfiber utilization, with a positive impact on animal productivity. However, information on how isoacids impact nutrientdigestibility in swine is limited. The objective of this experiment was to determine the optimal inclusion levelof an isoacid blend product based on apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD)of nutrients and fermentation products in the ileal digesta and feces of growing pigs fed a corn-soybean meal diet.Methods Twelve ileal cannulated pigs (20.9 ± 0.6 kg) were used in a 5-period crossover design with 6 diets and 2replicate pigs in each period. Dietary treatments consisted of increasing levels (0%, 0.5%, 0.75%, 1%, 1.25%, and 1.5%)of an isoacid blend (isobutyrate, isovalerate, and 2-methyl butyrate, 1:1:1) added to a corn-soybean meal basal diet.Each experimental period consisted of 14 d: 10 d for acclimatization to the diets, 2 d for fecal collection, and 2 dfor digesta collection.Results Isoacids supplementation quadratically improved the AID of hemicellulose (P < 0.05) and tended to improvethe AID of crude fiber (P < 0.1). The AID of most indispensable amino acids (except Met + Cys, Trp, and Val) as wellas the ATTD of crude protein, gross energy, neutral detergent fiber, and hemicellulose improved or tended to improvelinear or quadratically (P < 0.05 or P < 0.1). In addition, the ATTD values of Arg, His, Ile, Leu, Met + Cys, Phe, Thr, and Valincreased quadratically (P < 0.05). Collectively, 1% of isoacids inclusion resulted in the greatest response. Furthermore,isoacids supplementation tended to increase (P = 0.071, quadratically) the concentration of ammonia and decreased(P < 0.05) the concentrations of acetic acid and total volatile fatty acids with a tendency to decrease (P = 0.064) isovalericacid in the ileal digesta. In fecal samples, the proportion of acetic acid decreased (P < 0.05) quadratically, whereas the proportionsof propionic, valeric, and caproic acids tended to increase linearly and/or quadratically (P < 0.1).Conclusions Isoacids supplementation at 1% in swine diets can improve nutrient digestibility, particularly aminoacids and fiber at the ileal level and ATTD of crude protein, gross energy, and hemicellulose.展开更多
This study assessed the effects of reducing hydraulic retention times （HRTs） from 21 days to 10.5 days when anaerobically co-digesting pig manure and food waste. Continuously stirred tank reactors of 3.75 L working ...This study assessed the effects of reducing hydraulic retention times （HRTs） from 21 days to 10.5 days when anaerobically co-digesting pig manure and food waste. Continuously stirred tank reactors of 3.75 L working volume were operated in triplicate at 42℃. Digester HRT was progressively decreased from 21 to 15 days to 10.5 days, with an associated increase in organic loading rate （OLR） from 3.1 kg volatile solids （VS）·m^-3.day^-1 to 5.1 kg VS·m^3.day-1 to 7.25 kg VS.m^-3·day^-1. Reducing HRT from 21 days to 15 days caused a decrease in specific methane yields and VS removal rates. Operation at a HRT of 10.5 days initially resulted in the accumulation of isobutyric acid in each reactor. High throughput 16S rRNA gene sequencing revealed that this increase coincided with a shift in acidogenic bacterial populations, which most likely resulted in the increased isobutyric acid concentrations. This may in turn have caused the increase in relative abundance of Clocamonaceae bacteria, which syntrophically degrade non-acetate volatile fatty acids （VFAs） into H2 and CO2. This, along with the increase in abundance of other syntrophic VFA oxidizers, such as Spiorchatetes, suggests that VFA oxidation plays a role in digester operation at low HRTs. Reducing the HRT to below 21 days compromised the ability of the anaerobic digestion system to reduce enteric indicator organism counts below regulatory limits.展开更多
基金The National Natural Science Foundation of China(32302759,32372924)the CAST Youth Talent Support Project-Special Program for Doctoral Students(156-O-230-0000375-5)。
文摘Background Weaning-induced diarrhoea and growth retardation in piglets are associated with impaired intestinal barrier function and decreased levels of colonic short-chain fatty acids(SCFAs).Although SCFA supplementation has been proposed to mitigate these issues,the efficacy and optimal dosage of sodium isobutyrate remain unclear.Results We investigated the effects of sodium isobutyrate supplementation(500,1,000,2,000,and 4,000 mg/kg diet)on weaned piglets(Duroc×Landrace×Yorkshire,28 d of age;n=8).After a 28-d feeding trial,supplementation at 500–2,000 mg/kg significantly improved average daily gain and feed efficiency and reduced diarrhoea frequency,with maximal benefits observed at 1,000 mg/kg(P<0.0001).Additionally,500–1,000 mg/kg sodium isobutyrate supplementation increased the apparent digestibility of crude protein,organic matter,and crude fibre(P<0.05).Serum biochemical parameters were unaffected,although secretory immunoglobulin A(SIgA)levels significantly increased upon supplementation with 500–1,000 mg/kg(P<0.05).16S rRNA gene sequencing indicated that sodium isobutyrate increased the abundance of beneficial colonic microbiota.The 1,000 mg/kg group presented the most pronounced effect,with a significant increase of the relative abundance of Prevotella and the greatest improvement in SCFA concentrations(P<0.05).Metabolomics revealed elevated levels of colonic indole-3-lactic acid and 3-hydroxybutyrate upon supplementation with 1,000 mg/kg(P<0.05).Transcriptomic analyses indicated activation of protein digestion and absorption pathways,and PI3K-Akt signalling,marked by TSG-6 upregulation and the suppression of ISG15 and DDIT4 expression(P<0.05).Supplementation with 1,000 mg/kg was associated with improved intestinal barrier-related markers,including reduced serum D-lactate,diamine oxidase,and lipopolysaccharide levels,increased tight junction protein expression;activation of G protein-coupled receptors;and inhibition of TLR4/MyD88/NF-κB signalling(P<0.05),suggesting enhanced barrier function.Conclusions In conclusion,dietary supplementation with 1,000 mg/kg sodium isobutyrate was associated with improved intestinal morphology,reduced serum permeability,increased expression of tight junction proteins,and enhanced immune function in weaned piglets,suggesting enhanced colonic barrier function and providing dosage guidance and mechanistic insights for future applications.
基金financially supported by Zinpro Corporation(grant number:SA2300029,2022–2025).
文摘Background Isoacids are the product of branched-chain amino acid fermentation and are naturally producedin the hindgut by microbial fermentation. In ruminants, supplementation of isoacids as a feed additive improvesfiber utilization, with a positive impact on animal productivity. However, information on how isoacids impact nutrientdigestibility in swine is limited. The objective of this experiment was to determine the optimal inclusion levelof an isoacid blend product based on apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD)of nutrients and fermentation products in the ileal digesta and feces of growing pigs fed a corn-soybean meal diet.Methods Twelve ileal cannulated pigs (20.9 ± 0.6 kg) were used in a 5-period crossover design with 6 diets and 2replicate pigs in each period. Dietary treatments consisted of increasing levels (0%, 0.5%, 0.75%, 1%, 1.25%, and 1.5%)of an isoacid blend (isobutyrate, isovalerate, and 2-methyl butyrate, 1:1:1) added to a corn-soybean meal basal diet.Each experimental period consisted of 14 d: 10 d for acclimatization to the diets, 2 d for fecal collection, and 2 dfor digesta collection.Results Isoacids supplementation quadratically improved the AID of hemicellulose (P < 0.05) and tended to improvethe AID of crude fiber (P < 0.1). The AID of most indispensable amino acids (except Met + Cys, Trp, and Val) as wellas the ATTD of crude protein, gross energy, neutral detergent fiber, and hemicellulose improved or tended to improvelinear or quadratically (P < 0.05 or P < 0.1). In addition, the ATTD values of Arg, His, Ile, Leu, Met + Cys, Phe, Thr, and Valincreased quadratically (P < 0.05). Collectively, 1% of isoacids inclusion resulted in the greatest response. Furthermore,isoacids supplementation tended to increase (P = 0.071, quadratically) the concentration of ammonia and decreased(P < 0.05) the concentrations of acetic acid and total volatile fatty acids with a tendency to decrease (P = 0.064) isovalericacid in the ileal digesta. In fecal samples, the proportion of acetic acid decreased (P < 0.05) quadratically, whereas the proportionsof propionic, valeric, and caproic acids tended to increase linearly and/or quadratically (P < 0.1).Conclusions Isoacids supplementation at 1% in swine diets can improve nutrient digestibility, particularly aminoacids and fiber at the ileal level and ATTD of crude protein, gross energy, and hemicellulose.
文摘This study assessed the effects of reducing hydraulic retention times （HRTs） from 21 days to 10.5 days when anaerobically co-digesting pig manure and food waste. Continuously stirred tank reactors of 3.75 L working volume were operated in triplicate at 42℃. Digester HRT was progressively decreased from 21 to 15 days to 10.5 days, with an associated increase in organic loading rate （OLR） from 3.1 kg volatile solids （VS）·m^-3.day^-1 to 5.1 kg VS·m^3.day-1 to 7.25 kg VS.m^-3·day^-1. Reducing HRT from 21 days to 15 days caused a decrease in specific methane yields and VS removal rates. Operation at a HRT of 10.5 days initially resulted in the accumulation of isobutyric acid in each reactor. High throughput 16S rRNA gene sequencing revealed that this increase coincided with a shift in acidogenic bacterial populations, which most likely resulted in the increased isobutyric acid concentrations. This may in turn have caused the increase in relative abundance of Clocamonaceae bacteria, which syntrophically degrade non-acetate volatile fatty acids （VFAs） into H2 and CO2. This, along with the increase in abundance of other syntrophic VFA oxidizers, such as Spiorchatetes, suggests that VFA oxidation plays a role in digester operation at low HRTs. Reducing the HRT to below 21 days compromised the ability of the anaerobic digestion system to reduce enteric indicator organism counts below regulatory limits.
