All-trans retinoic acid alleviates transmissible gastroenteritis virus-induced intestinal inflammation and barrier dysfunction in weaned piglets

Background Transmissible gastroenteritis virus(TGEV)is one of the main pathogens causing severe diarrhea of pig-lets.The pathogenesis of TGEV is closely related to intestinal inflammation.All-trans retinoic acid(ATRA)is the main active metabolite of vitamin A,which has immunomodulatory and anti-inflammatory properties.However,it is unclear whether ATRA can alleviate TGEV-induced intestinal inflammation and barrier dysfunction in piglets.This study aimed to investigate the effects of ATRA on growth performance,diarrhea,intestinal inflammation and intesti-nal barrier integrity of TGEV-challenged piglets.Methods In a 19-d study,32 weaned piglets were randomly divided into 4 treatments:Control group(basal diet),TGEV group(basal diet+TGEV challenge),TGEV+ATRA5 group(basal diet+5 mg/d ATRA+TGEV challenge)and TGEV+ATRA15 group(basal diet+15 mg/d ATRA+TGEV challenge).On d 14,piglets were orally administered TGEV or the sterile medium.Results Feeding piglets with 5 and 15 mg/d ATRA alleviated the growth inhibition and diarrhea induced by TGEV(P<0.05).Feeding piglets with 5 and 15 mg/d ATRA also inhibited the increase of serum diamine oxidase(DAO)activ-ity and the decrease of occludin and claudin-1 protein levels in jejunal mucosa induced by TGEV,and maintained intestinal barrier integrity(P<0.05).Meanwhile,5 mg/d ATRA feeding increased the sucrase activity and the expres-sions of nutrient transporter related genes(GLUT2 and SLC7A1)in jejunal mucosa of TGEV-challenged piglets(P<0.05).Furthermore,5 mg/d ATRA feeding attenuated TGEV-induced intestinal inflammatory response by inhibit-ing the release of interleukin(IL)-1β,IL-8 and tumor necrosis factor-α(TNF-α),and promoting the secretion of IL-10 and secretory immunoglobulin A(sIgA)(P<0.05).Feeding 5 mg/d ATRA also down-regulated the expressions of Toll-like receptors and RIG-I like receptors signaling pathway related genes(TLR3,TLR4,RIG-I,MyD88,TRIF and MAVS)and the phosphorylation level of nuclear factor-κB-p65(NF-κB p65),and up-regulated the inhibitor kappa B alpha(IκBα)protein level in jejunal mucosa of TGEV-challenged piglets(P<0.05).Conclusions ATRA alleviated TGEV-induced intestinal barrier damage by inhibiting inflammatory response,thus improving the growth performance and inhibiting diarrhea of piglets.The mechanism was associated with the inhibi-tion of NF-κB signaling pathway mediated by TLR3,TLR4 and RIG-I.

Effects of different starch structures on energy metabolism in pigs

Background Starch is a major component of carbohydrates and a major energy source for monogastric animals.Starch is composed of amylose and amylopectin and has different physiological functions due to its different structure.It has been shown that the energy supply efficiency of amylose is lower than that of amylopectin.However,there are few studies on the effect of starch structure on the available energy of pigs.The purpose of this study was to measure the effect of different structures of starch in the diet on the net energy(NE)of pigs using a comparative slaughter method and to establish a prediction equation to estimate the NE of starch with different structures.Fifty-six barrows(initial BW 10.18±0.11 kg)were used,and they were housed and fed individually.Pigs were divided into 7 treatments,with 8 replicates for each treatment and 1 pig for each replicate.One of the treatments was randomly selected as the initial slaughter group(ISG).Pigs in the remaining treatments were assigned to 6 diets,fed with basic diet and semi-pure diets with amylose/amylopectin ratio(AR)of 3.09,1.47,0.25,0.15 and 0.12,respectively.The experiment lasted for 28 d.Results Results showed that compared with the high amylose(AM)groups(AR 3.09 and 1.47),the high amylopectin(AP)group(AR 0.15)significantly increased the final BW,average daily weight gain and average daily feed intake of pigs(P<0.05),but the F:G of the AM group was lower(P<0.01).In addition,AR 0.15 and 0.12 groups have higher(P<0.01)nutrient digestibility of dry matter,crude protein,gross energy and crude ash.Meanwhile,compared with other groups,AR 0.15 group has a higher(P<0.05)NE intake and energy retention(RE).The regressive equation for predicting with starch structures was established as RE=1,235.243-48.298AM/AP(R^(2)=0.657,P=0.05).Conclusions In conclusion,NE intake and RE of pigs augmented with the increase of dietary amylopectin content,indicating that diets high in amylopectin were more conducive to promoting the growth of pigs in the late conserva-tion period.

Solid state fermentation of rapeseed cake with Aspergillus niger for degrading glucosinolates and upgrading nutritional value

Background： Rapeseed cake is a good source of protein for animal feed but its utilization is limited due to the presence of anti-nutritional substances, such as glucosinolates （GIs）, phytic acid, tannins etc. In the present study, a solid state fermentation （SSF） using Aspergillus niger was carried out with the purpose of degrading glucosinolates and improving the nutritional quality of rapeseed cake （RSC）. The effects of medium composition and incubation conditions on the GIs content in fermented rapeseed cake （FRSC） were investigated, and chemical composition and amino acid in vitro digestibility of RSC substrate fermented under optimal conditions were determined. Results： After 72 h of incubation at 34℃, a 76.89% decrease in GIs of RSC was obtained in solid medium containing 70% RSC, 30% wheat bran at optimal moisture content 60% （w/w）. Compared to unfermented RSC, trichloroacetic acid soluble protein （TCA-SP）, crude protein and ether extract contents of the FRSC were increased （P〈 0.05） 103.71, 23.02 and 23.54%, respectively. As expected, the contents of NDF and phytic acid declined （P〈 0.05） by 9.12 and 44.60%, respectively. Total amino acids （TAA） and essential amino acids （EAA） contents as well as AA in vitro digestibility of FRSC were improved significantly （P 〈 0.05）. Moreover, the enzyme activity of endoglucanase, xylanase, acid protease and phytase were increased （P 〈 0.05） during SSF. Conclusions： Our results indicate that the solid state fermentation offers an effective approach to improving the quality of proteins sources such as rapeseed cake.

Effect of different dietary protein levels and amino acids supplementation patterns on growth performance, carcass characteristics and nitrogen excretion in growing-finishing pigs

Background:This study was conducted to determine the effects of different dietary protein levels and amino acids supplementation patterns in low protein diets on the growth performance,carcass characteristics and nitrogen excretion in growing-finishing pigs.Forty-two barrows(25.00±0.39 kg)were randomly assigned to 7 diets.Diet 1:the high crude protein diet with balanced for 10 essential amino acids(EAAs).Diet 2:the medium crude protein diet with 2%(approx)decreased protein level of Diet 1 and balanced 10 EAAs.Diet 3:the low crude protein diet with 4%decreased protein level of Diet 1 and balanced 10 EAAs.The protein levels of Diet 4,5,6 and 7 were the same as that of Diet 3.Diet 4 was only balanced for lysine(Lys),methionine(Met),threonine(Thr)and tryptophan(Trp);Diet 5 and 6 were further supplemented with extra isoleucine(Ile)or valine(Val),respectively;Diet 7 was further supplemented with extra Ile+Val.Results:Over the 112 days trial,the reduction of dietary protein by 2%or 4%with balanced10 EAAs significantly decreased nitrogen excretion(P<0.05),but had no effects on growth performance and carcass characteristics(P>0.05).In low protein diet,Val supplementation significantly increased body weight gain at 25–50 kg phase(P<0.05),while Ile supplementation at 75–100 kg phase and 100–125 kg phase significantly reduced the ratio of feed to gain(P<0.05).No effect of different dietary protein levels and amino acids supplementation patterns in low protein diets on carcass characteristics was observed(P>0.05).The total N excretion of pigs supplemented with only Lys,Met,Thr and Trp was numerically higher than that of pigs fed with extra Ile,or Val,or Ile+Val diets.Conclusion:In low protein diet,Val is more required than Ile in the early growing phage(25–50 kg),while Ile becomes more required in the late growing and finishing phage(75–125 kg).

Effect of sialyllactose on growth performance and intestinal epithelium functions in weaned pigs challenged by enterotoxigenic Escherichia Coli

Background:Sialyllactose(SL)is one of the most abundant oligosaccharides present in porcine breast milk.However,little is known about its effect on growth performance and intestinal health in weaned pigs.This study was conducted to explore the protective effect of SL on intestinal epithelium in weaned pigs upon enterotoxigenic Escherichia coli(ETEC)challenge.Methods:Thirty-two pigs were randomly divided into four treatments.Pigs fed with a basal diet or basal diet containing SL(5.0 g/kg)were orally infused with ETEC or culture medium.Results:SL supplementation elevated the average daily gain(ADG)and feed efficiency in the ETEC-challenged pigs(P<0.05).SL also improved the digestibilities of dry matter(DM),gross energy(GE),and ash in non-challenged pigs(P<0.05).Moreover,SL not only elevated serum concentrations of immunoglobulins(IgA,IgG,and IgM),but also significantly decreased the serum concentrations of inflammatory cytokines(TNF-α,IL-1β,and IL-6)upon ETEC challenge(P<0.05).Interestingly,SL increased the villus height,the ratio of villus height to crypt depth(V:C),and the activities of mucosal sucrase and maltase in the jejunum and ileum(P<0.05).SL also elevated the concentrations of microbial metabolites(e.g.acetic acid,propanoic acid,and butyric acid)and the abundance of Lactobacillus,Bifidobacterium,and Bacillus in the cecum(P<0.05).Importantly,SL significantly elevated the expression levels of jejunal zonula occludins-1(ZO-1),occluding,and fatty acid transport protein-4(FATP4)in the ETEC-challenged pigs(P<0.05).Conclusions:SL can alleviate inflammation and intestinal injury in weaned pigs upon ETEC challenge,which was associated with suppressed secretion of inflammatory cytokines and elevated serum immunoglobulins,as well as improved intestinal epithelium functions and microbiota.

Differential expression, molecular cloning,and characterization of porcine beta defensin 114

Background:β-defensins have attracted considerable research interest because of their roles in protecting hosts from various pathogens.This study was conducted to investigate the expression profiles of the porcineβ-defensin114(PBD114)in different breeds and in response to infections.Moreover,the function of PBD114 protein was partially investigated.Methods:Six Tibetan pigs(TP)and six DLY(Duroc×Landrace×Yorkshire)pigs were slaughtered to explore the expression profiles of PBD114 in different breeds and tissues.For infection models,sixteen DLY pigs were divided into two groups and challenged either with sterile saline or E.coli K88.The recombinant protein PBD114(r PBD114)was obtained by using a heterologous expression system in E.coli.Results:PBD114 gene was highly expressed in tissues such as the intestine,liver,spleen,and thymus.Interestingly,the expression level of PBD114 gene was higher in the TP pigs than in the DLY pigs(P<0.05),and was significantly elevated upon E.coli K88 challenge(P<0.05).The nucleotide sequences of PBD114 from Tibetan and DLY pigs was identical,and both showed a 210-bp open reading frame encoding a 69-amino acid mature peptide.To explaore the function of PBD114 protein,PBD114 gene was successfully expressed in E.coli Origami B(DE3)and the molecular weight of the r PBD114 was estimated by SDS-PAGE to be 25 k Da.The r PBD114 was purified and mass spectrometry verified the protein as PBD114.Importantly,r PBD114 showed antimicrobial activities against E.coli DH5αand E.coli K88,and the minimal inhibitory concentrations(MICs)were 64 and 128μg/m L,respectively.Hemolytic and cytotoxicity assays showed that r PBD114 did not affect cell viability under physiological concentrations.Conclusions:PBD114 is an infection response gene that is differentially-expressed between different porcine breeds and tissues.The antimicrobial activity of PBD114 protein,against pathogens such as the E.coli K88,suggested that it may serve as a candidate for the substitution of conventionally used antibiotics.

Tannic acid prevents post-weaning diarrhea by improving intestinal barrier integrity and function in weaned piglets

Background:Tannic acid(TA)is potential to reduce diarrhea in weaning pigs,but knowledge about the influence of TA on intestinal barrier integrity and function is still scarce.This experiment was conducted to investigate the effects of dietary TA supplementation on growth performance,diarrhea rate,intestinal barrier integrity and function of weaned pigs.Methods:A total of 108 crossbred(Duroc×Landrace×Yorkshire)piglets,with an initial average body weight of 6.60±0.27 kg,were allotted to 3 groups(6 pigs/pen and 6 replicates/group)in a randomized complete block design according to their gender and body weight.Piglets were fed the basal diet with 0(control,CON),0.2%and 1.0%TA,respectively.The trial lasted for 28 d.Results:Compared with the CON group,dietary 0.2%and 1.0%TA supplementation didn’t affect ADFI,ADG and F:G(P>0.05),but reduced diarrhea rate,diarrhea index and diarrhea score of piglets(P<0.05),reduced diamine oxidase(DAO)activity and D-lactic acid concentration in serum(P<0.01).The higher occludin expression and localization were observed in the duodenum,jejunum and ileum after supplementation with 0.2%or 1.0%TA(P<0.05).Adding 0.2%TA to diet significantly decreased crypt depth,increased villus height/crypt depth ratio in the duodenum(P<0.05),and dietary 1.0%TA tended to decrease crypt depth(P<0.10)and significantly decreased villus height(P<0.05)of the ileum.Moreover,lower malondialdehyde content in the ileum was detected in the pigs fed 1.0%TA(P<0.05).In the duodenum,both 0.2%and 1.0%TA groups had higher occludin(OCLN)mRNA and 0.2%TA group had higher zonula occludens-2(ZO-2)level(P<0.05).Meanwhile,dietary 1.0%TA supplementation tended to up-regulate OCLN mRNA levels in the jejunum(P<0.10)and 0.2%TA supplementation tended to up-regulate zonula occludens-1(ZO-1)mRNA levels in the ileum(P<0.10).Conclusion:In conclusion,dietary supplementation of 0.2%or 1.0%TA could effectively alleviate postweaning diarrhea without altering growth performance in weaned piglets,which might be achieved by improving intestinal barrier integrity and function.

Effects of benzoic acid(Vevo Vitall) on the performance and jejunal digestive physiology in young pigs

Background： As a organic acid, benzoic acid has become one of the most important alternatives for antibiotics,and its beneficial effect on performance in animals has been proven for a decade. However, knowledge of the effects of benzoic acid on jejunal digestive physiology, especially the antioxidant capacity and mucosal glucagon-like peptide2（GLP-2） concentrations is lacking.Methods： A total of 20 barrows [Duroc ×（Yorkshire × Landrace）] with an average body weight（BW） of 18.75 ± 0.2 kg were used in a 14-d trial to determine the potential mechanisms of benzoic acid supplementation on the performance,nutrient digestibility and jejunal digestive physiology in young pigs. All pigs were randomly allotted to 1 of 2 diets supplemented with 0 or 5000 mg/kg benzoic acid.Results： Relative to the control, benzoic acid supplementation increased the average daily feed intake（ADFI）, and average daily gain（ADG） in young pigs（P 〈 0.05）, improved the apparent total tract digestibility of dry matter（DM）,crude protein（CP）, ether extract（EE）, gross energy（GE） and crude ash（P 〈 0.05）, and enhanced the activities of trypsin,lipase and amylase in the jejunum（P 〈 0.05）. Similarly, relative to the control, supplementing benzoic acid in the diet resulted in a trend to reduce the p H values of the digesta（P = 0.06）, decreased crypt depth and increased the villus height to crypt depth ratio（P 〈 0.05） in the jejunum of pigs. Finally, benzoic acid supplementation increased the mR NA expression and concentration of glucagon-like peptide 2 and the activities of glutathione peroxidase and superoxide dismutase in the jejunal mucosa of young pigs（P 〈 0.05）.Conclusions： In conclusion, supplementation with 5000 mg/kg benzoic acid improved the performance of young pigs through promoting nutrient digestion, improving jejunal antioxidant capacity, and maintaining the jejunal morphology in young pigs.

Apoptotic extracellular vesicles are metabolized regulators nurturing the skin and hair

Over 300 billion of cells die every day in the human body,producing a large number of endogenous apoptotic extracellular vesicles(apoEVs).Also,allogenic stem cell transplantation,a commonly used therapeutic approach in current clinical practice,generates exogenous apoEVs.It is well known that phagocytic cells engulf and digest apoEVs to maintain the body’s homeostasis.In this study,we show that a fraction of exogenous apoEVs is metabolized in the integumentary skin and hair follicles.Mechanistically,apoEVs activate the Wnt/β-catenin pathway to facilitate their metabolism in a wave-like pattern.The migration of apoEVs is enhanced by treadmill exercise and inhibited by tail suspension,which is associated with the mechanical force-regulated expression of DKK1 in circulation.Furthermore,we show that exogenous apoEVs promote wound healing and hair growth via activation of Wnt/β-catenin pathway in skin and hair follicle mesenchymal stem cells.This study reveals a previously unrecognized metabolic pathway of apoEVs and opens a new avenue for exploring apoEV-based therapy for skin and hair disorders.

Effect of fermented rapeseed meal on growth performance,nutrient digestibility,and intestinal health in growing pigs

To explore the effects of fermented rapeseed meal(FRSM)on growth performance and intestinal health,a total of 30 growing pigs were randomly allotted to three treatments consisting of corn-soybean meal diet(CSD),rapeseed meal diet(RSD),and fermented rapeseed meal diet(FRSD).Results showed that compared with RSD,FRSD feeding increased the average daily gain and final body weight in pigs(P<0.01).Compared with RSD feeding,FRSD feeding elevated the apparent digestibility of crude protein,acid detergent fiber,and ether extract in pigs(P<0.01).Moreover,the FRSD group exhibited greater apparent ileal digestibility of His,Thr,Lys,and Ser than the RSD group(P<0.01).The digestible energy,metabolic energy,and nitrogen utilization were higher in the FRSD and CSD groups than in the RSD group(P<0.01).As compared to the RSD,FRSD feeding decreased the serum concentration of leptin but significantly increased the concentrations of immunoglobulin(Ig)A,IgG,ghrelin,and enzyme activities of amylase,lipase,and trypsin in the pancreas(P<0.05).Interestingly,the villus height,the ratio of villus height to crypt depth,and the activities of brush border enzymes(e.g.,maltase and sucrase)in the small intestine were higher in the CSD and FRSD groups than in the RSD group(P<0.05).As compared to the RSD,the FRSD feeding not only increased the expression level of the occludin in the small intestinal epithelium(P<0.05)but also elevated the expression levels of claudin-1,MUC1,and PepT1 genes in the duodenum,and elevated the expression levels of SGLT1 and CAT1 genes in the jejunum(P<0.05).Importantly,FRSD feeding significantly decreased the abundance of Escherichia coli,but increased the abundance of Lactobacillus and the content of butyrate in the cecum and colon(P<0.05).These results indicated that compared with rapeseed meal,fermented rapeseed meal exhibited a positive effect on improving the growth performance and intestinal health in growing pigs,and the results may also help develop novel protein sources for animal nutrition and the feed industry.

Apoptotic vesicles rejuvenate mesenchymal stem cells via Rab7-mediated autolysosome formation and alleviate bone loss in aging mice

Aging skeletons display decreased bone mass,increased marrow adiposity,and impaired bone marrow mesenchymal stem cells(MSCs).Apoptosis is a programmed cell death process that generates a large number of apoptotic vesicles(apoVs).Dysregulated apoptosis has been closely linked to senescence-associated diseases.However,whether apoVs mediate agingrelated bone loss is not clear.In this study,we showed that young MSC-derived apoVs effectively rejuvenated the nuclear abnormalities of aged bone marrow MSCs and restored their impaired self-renewal,osteo-/adipo-genic lineage differentiation capacities via activating autophagy.Mechanistically,apoptotic young MSCs generated and enriched a high level of Ras-related protein 7(Rab7)into apoVs.Subsequently,recipient aged MSCs reused apoV-derived Rab7 to restore autolysosomes formation,thereby contributing to autophagy flux activation and MSC rejuvenation.Moreover,systemic infusion of young MSC-derived apoVs enhanced bone mass,reduced marrow adiposity,and recused the impairment of recipient MSCs in aged mice.Our findings reveal the role of apoVs in rejuvenating aging-MSCs via restoring autolysosome formation and provide a potential approach for treating age-related bone loss.

Effect of dietary supplementation of Bacillus coagulans or yeast hydrolysates on growth performance,antioxidant activity,cytokines and intestinal microflora of growing-finishing pigs

This study was to investigate the effects of dietary supplementation of Bacillus coagulans(BC) and yeast hydrolysates(YH) on growth performance,antioxidant activity,cytokines and intestinal microflora of growing-finishing pigs.Thirty-six barrows(initial BW=26.87±2.65 kg) were assigned randomly to 3 treatments with 4 replicates,3 pigs per replicate.Pigs in the control group(CON) were fed a basal diet,and the diets for the other 2 groups were the basal diet plus BC at 200 mg/kg and the basal diet plus YH at 3,000 mg/kg.The trial lasted for 104 d.Compared with CON,YH treatment significantly increased average daily gain(ADG) and average daily feed intake(ADFI) during the finishing phase(P <0.05),and significantly enhanced ADG during the overall period(P <0.05).Dietary inclusion of BC tended to increase ADFI during the finishing period(P=0.08).Compared with CON,BC treatment imp roved lysozyme(LZM),complement 3(C3),complement 4(C4),interlenkin-10(IL-10) and total antioxidant capacity(T-AOC) level in serum(P <0.05).Dietary inclusion of YH enhanced the serum IL-10 level(P <0.05) and tended to increase T-AOC level(P=0.06).Dietary inclusion of YH elevated(P <0.05) the number of Lactobacillus and Bacillus in cecal contents of pigs,promoted the populations of Bifidobacterium and Bacillus in colonic contents.Moreover,the BC diet increased(P <0.05) the count of Bifidobacterium in colonic contents.These results indicated that dietary BC supplementation is beneficial to improve the immunity.Dietary YH supplementation promoted the growth performance and the populations of beneficial bacteria in the hindgut of the growing-finishing pigs.

Effects of benzoic acid,Bacillus coagulans and oregano oil combined supplementation on growth performance,immune status and intestinal barrier integrity of weaned piglets

This experiment was conducted to investigate the effects of benzoic acid,Bacillus coagulans and oregano oil combined supplementation on growth performance,immune status and intestinal barrier integrity of piglets.In a 26-d experiment,25 piglets were randomly assigned to 5 treatments:1)a basal diet,negative control(NC),2)NC added with antibiotics,positive control(PC);3)NC added with benzoic acid at 3,000 g/t and Bacillus coagulans at 400 g/t(AB);4)NC added with benzoic acid at 3,000 g/t and o regano oil at 400 g/t(AO);5)NC added with 3,000 g/t benzoic acid and Bacillus coagulans at 400 g/t and oregano oil at 400 g/t(ABO);On d 27,all piglets were euthanized to obtain jejunal mucosa to measure immune status and intestinal barrier integrity.Results showed that pigs fed AB diet increased the final body weight and average daily body weight gain and decreased the ratio of feed to gain co mpared with NC group(P<0.05).Co mpared with NC group,AB,AO and ABO decreased serum tumor necrosis factor-a concentration and ABO decreased interleukin-1βconcentration in serum and jejunal mucosa(P<0.05).Compared with NC group,AB upregulated mRNA expressions of sodium-glucose cotransportel,claudin-1,occludin and mucin2 in jejunal mucosa and the populations of Bifidobacterium and Bacillus in cecal digesta(P<0.05).Compared with NC group,ABO increased jejunal mucosal occludin mRNA abundance and Bifidobacterium population in cecal digesta,and decreased Escherichia coli population in cecal digesta(P<0.05).Furthermore,AB and ABO increased Bacillus population in cecal digesta compared with PC group(P<0.05).These results indicated that dietary AB supplementation could improve growth performance and intestinal barrier integrity of piglets when fed antibiotic-free diets,which was possibly associated with the improvement of immune status and intestinal microflora.Dietary ABO supplementation is also beneficial to improve immune status and intestinal barrier integrity and micro flora of piglets.

Dietary lycopene supplementation improves meat quality,antioxidant capacity and skeletal muscle fiber type transformation in finishing pigs

This study aimed to investigate effects of dietary lycopene supplementation on meat quality,antioxidant ability and muscle fiber type transformation in finishing pigs.In a 70-day experiment,18 DurocLandraceYorkshire barrows were randomly allocated to 3 dietary treatments including a basal diet supplemented with 0,100 and 200 mg/kg lycopene,respectively.Each dietary treatment had 6 replicates with one pig each.Results showed that dietary 200 mg/kg lycopene supplementation increased muscle redness a^(*)value,intramuscular fat and crude protein contents,and decreased muscle lightness L^(*)and yellowness b^(*)values(P<0.05),suggesting that addition of 200 mg/kg lycopene to the diet of finishing pigs improved color,nutritional value and juiciness of pork after slaughter.Results also showed that dietary lycopene supplementation enhanced antioxidant capacity of finishing pigs(P<0.05).Moreover,dietary supplementation of 200 mg/kg lycopene significantly increased slow myosin heavy chain(MyHC)protein level and slow-twitch fiber percentage,and decreased fast MyHC protein level and fast-twitch fiber percentage(P<0.05),suggesting that the addition of 200 mg/kg lycopene to the diet of finishing pigs promoted muscle fiber type conversion from fast-twitch to slow-twitch.Together,we provide the first evidence that dietary 200 mg/kg lycopene supplementation improves meat quality,enhances antioxidant capacity and promotes muscle fiber type transformation from fast-twitch to slow-twitch in finishing pigs.

Supplementing daidzein in diets improves the reproductive performance, endocrine hormones and antioxidant capacity of multiparous sows

Certain hormones play important roles in modulating mammalian reproductive behaviour.Daidzein is a well-known isoflavonic phytoestrogen that possesses oestrogenic activity.This study was conducted to probe the effects of daidzein supplementation in gestation diets on the reproductive performance in sows.A total of 120 multiparous sows(Landrace x Yorkshire)were randomly assigned to 2 groups(n=60)and fed either a base diet(control)or one containing 200 mg/kg daidzein during gestation.We discovered that daidzein supplementation significantly increased the total number of piglets born per litter and number of piglets born alive per litter(P<0.05),decreased the farrowing time(P<0.05)and increased the serum oestrogen and progesterone concentrations(P<0.05)at 35 d of gestation.Moreover,serum immunoglobulin G(IgG)concentration and superoxide dismutase(SOD)and glutathione peroxidase(GSH-Px)activities were higher in the daidzein-treated group than in the control group at35 d of gestation(P<0.05).Daidzein increased the serum SOD activity and total anti-oxidative capacity(T-AOC)at 85 d of gestation(P<0.05).Interestingly,daidzein elevated the expression levels of the sodium-coupled neutral amino acid transporter 1(SLC38 A1)and insulin-like growth factor 1(IGF-1)genes in the placenta(P<0.05).These results suggest that daidzein ingestion could improve sow reproductive performance by changing serum hormones,elevating anti-oxidative capacity and upregulating critical functional genes in the placenta.

Lower abundance of Bacteroides and metabolic dysfunction are highly associated with the post-weaning diarrhea in piglets

Growing evidences show a direct link between diarrhea and disorders of gut microbiota in pigs.However,whether there are microbial markers associated with post-weaning diarrhea remains unknown.In the current study,we compared the microbial community,functions and metabolites between healthy weaned piglets(group H,n=7)and piglets with post-weaning diarrhea(group D,n=7),in order to find out diarrhea associated microbial markers.Each of 7 fecal samples was collected from H and D piglets(weaned at 21 d and sampled at 26 d).The metagenomic and untargeted metabolomic analysis revealed that the microbial composition,function and metabolic profile in D pigs was considerably reshaped,including the reduced abundance and number of Bacteroides,which significantly correlated with the diarrhea status of host.The carbohydrate metabolism,biosynthesis and metabolism,lipid metabolism,amino acid metabolism,and the activity of glycan and carbohydrates digestion related enzymes showed extensively down-regulated in D pigs compared with H pigs.Diarrhea significantly changed the metabolic profiles of fecal microbiota,and most of the altered metabolites were negatively or positively correlated with the change in the abundance of Bacteroides.In conclusion,the lower abundance of Bacteroides and its associated metabolic dysfunction may be regarded as microbial markers of physiological post-weaning diarrhea in piglets.

Prevotella-rich enterotype may benefit gut health in finishing pigs fed diet with a high amylose-to-amylopectin ratio

To investigate the influence of baseline enterotypes and dietary starch type on the concentration of short-chain fatty acids(SCFA),numbers of butyrate producing bacteria and the expression of genes related to intestinal barrier and inflammatory response in the colon of finishing pigs,a 60-d in vivo trial was conducted.A 2-wk pre-trial with 102 crossbred(Duroc×[Landrace×Yorkshire])finishing barrows(90 d old)was conducted to screen enterotypes.Then,a total of 32 pigs(87.40±2.76 kg)with high(HPBR,>14)and low(LPBR,<2)Prevotella-to-Bacteroides ratios(PBR)in equal measure were selected and randomly divided into 4 groups with 8 replicates per group and 1 pig per replicate.The trial was designed following a 2(PBR)×2(amylose-to-amylopectin ratio,AMR)factorial arrangement.Pigs with different PBR were fed diets based on corn-soybean meal with high AMR(HAMR,1.24)or low AMR(LAMR,0.23),respectively.Results showed that neither PBR nor AMR influenced the growth performance of pigs.HPBR pigs fed HAMR diet had a higher number of colonic Clostridium cluster XIVa and higher gene expression of butyrate kinase compared to the LPBR pigs(P<0.05).The HPBR pigs fed HAMR diets also had increased colonic concentrations of total SCFA and propionate compared to the LPBR pigs(P<0.05).Comparing with other pigs,HPBR pigs fed HAMR diets showed a lower(P<0.05)expression of histone deacetylases(HDAC)gene and higher(P<0.05)expression of G protein-coupled receptor 43 gene(GPR 43)in the colonic mucosa.The interaction(P<0.05)of HPBR and HAMR was also found to decrease the gene expression of interleukin(IL)-6,IL-12,IL-1βand tumor necrosis factor-α(TNF-α)in colonic mucosa.These findings show that HAMR diet increased the abundance and activity of butyrate-producing bacteria and the concentration and absorption of SCFA,which may be associated with the decreased gene expression of inflammatory cytokines in the colonic mucosa of pigs with Prevotella-rich enterotype.All these alterations are likely to have a positive effect on the intestinal health of finishing pigs.

Tannic acid extracted from gallnut prevents post-weaning diarrhea and improves intestinal health of weaned piglets

This experiment was conducted to evaluate the effects of different levels of tannic acid(TA)on growth performance,diarrhea rate,nutrient digestibility and intestinal health in weaned piglets.A total of 180 weaned piglets(Duroc×Landrace×Yorkshire,24 d of age,initial average BW=7.77±0.17 kg)were allotted to 5 groups(6 pigs/pen and 6 replicates/group)in a randomized complete block design according to their gender and body weight.Piglets were fed a basal diet,or the basal diet supplemented with 0.05%,0.1%,0.2%or 0.4%TA for 28 d.The supplementary levels of TA in the diets were obtained by adding tannalbin containing 51%TA and 40.17%protein.The results showed that,compared with the CON group,dietary TA did not affect ADFI,ADG or F:G,and linearly reduced(P<0.01)the diarrhea rate and diarrhea index of piglets.There were no significant effects on apparent total tract digestibility(ATTD)in the 0.05%,0.1%and 0.2%TA groups,while negative effects(P<0.05)on apparent digestibility of crude protein and gross energy were observed in the 0.4%TA group.In addition,the nutrient digestibility of dry matter,crude protein and gross energy linearly decreased(P<0.01)with the increase of TA dosage.Supplementation of TA increased(P<0.05)the villus height of the duodenum and jejunum,as well as increased(P<0.05)catalase(CAT)activity in serum.Dietary TA improved(P<0.05)the Bacillus counts in cecal digesta.Further,TA significantly improved(P<0.05)Bacillus counts and reduced(P<0.05)the Escherichia coli counts in colonic digesta.The concentration of acetic acid,pro pionic acid,butyric acid and isovaleric acid in cecal digesta were significantly increased(P<0.05).The mRNA expression level of zonula occludens-1(Z0-1),zonula occludens-2(ZI-2),and claudin-2(CLDN-2)in the jejunum were greater(P<0.05)in TA supplemented groups.The study showed that,compared to the control,TA prevented post-weaning diarrhea and improved intestinal health of weaned piglets,and the appropriate level of TA supplementation would be from 0.1%to 0.2%.

Effects of soybean raffinose on growth performance,digestibility,humoral immunity and intestinal morphology of growing pigs

There are appreciable does of raffinose in soybean,but the impacts of raffinose on pigs are poorly investigated.We used 2 experiments to investigate the influence of soybean raffinose on growth per-formance,digestibility,humoral immunity and intestinal morphology of growing pigs.In Exp.1,a total of 30 crossbred(Duroc×Landrace×Yorkshire)barrows(21.93±0.43 kg)were randomly divided into 3 groups,and were fed with the control diet,the control diets supplemented with 0.2%and 0.5%raffinose,respectively,for 21 d.Results showed that the addition of 0.2%or 0.5%raffinose reduced(P<0.05)average daily feed intake(ADFI),average daily gain(ADG)and nutrient digestibility,and dietary 0.5%raffinose increased the ratio of feed to gain(P<0.05).For serum indexes,dietary 0.5%raffinose decreased growth hormone and increased glucagon-like peptide-2,immunoglobulin G,tumor necrosis factor-α(TNF-α)and interleukin-6 concentration(P<0.05).In Exp.2,a total of 24 crossbred barrows(38.41±0.45 kg)were randomly divided into 3 groups,and were fed with the control diet(ad libitum),the raffinose diet(0.5%raffinose,ad libitum),and the control diet in the same amount as the raffinose group(feed-pair group)for 14 d,respectively.Compared with the control diet,dietary 0.5%raffinose decreased ADFI(P<0.05).Intriguingly,the raffinose group had lower ADG than the feed-pair group,lower nutrient digestibility,lower amylase activity in duodenum,lower amylase,lipase and trypsin ac-tivities in jejunum and higher TNF-αconcentration in serum compared with the other 2 groups,and a higher ratio of villus height to crypt depth compared with the control group(P<0.05).These results showed that soybean raffinose could reduce feed voluntary intake and body gain while improving in-testinal morphology without a significant negative influence on immunity.Taken together,dietary raffinose could decrease growth performance by reducing both feed intake and nutrient digestibility while inducing humoral immune response of growing pigs.

Dietary protein levels and amino acid supplementation patterns alter the composition and functions of colonic microbiota in pigs

Different dietary nitrogen(N) patterns may have different effects on gut microbiota.To investigate the effects of different crude protein(CP) levels or essential amino acids(EAA) supplementation patterns on the structure and functions of colonic microbiota,42 barrows(25±0.39 kg) were randomly assigned to 7 dietary treatments including:diet 1,a high CP diet with balanced 10 EAA;diet 2,a medium CP diet with approximately 2% decreased CP level from diet 1 and balanced 10 EAA;diets 3,4,5,6 and 7,low CP diets with 4% decreased CP level from diet 1.Specifically,diet 3 was only balanced for Lys,Met,Thr and Trp;diets 4,5 and 6 were further supplemented with IIe,Val and IIe+Val on the basis of diet 3,respectively;and diet 7 was balanced for 10 EAA.Results over a 110-d trial showed that reducing the CP level by 2% or4% dramatically decreased N intake and excretion(P <0.05) in the presence of balanced 10 EAA,which was not observed when altering the EAA supplementation patterns in low CP diet(-4%).With balanced10 EAA,2% reduction in dietary CP significantly reduced Firmicutes-to-Bacteroidetes(F:B) ratio and significantly elevated the abundance of Prevotellaceae NK3 B31(P <0.05);whereas 4% reduction evidently increased the abundances of Proteobacteria,Succinivibrio and Lachnospiraceae XPB1014(P <0.05).Among the 5 low CP diets(-4%),supplementation with Ile,or Val+Ile,or balanced 10 EAA increased F:B ratio and the abundance of Proteobacteria.In addition,the predicted functions revealed that different CP levels and EAA balanced patterns dramatically altered the mRNA expression profiles of N-metabolizing genes,the "N and energy metabolism" pathways or the metabolism of some small substances,such as amino acids(AA) and vitamins.Our findings suggested that reducing the dietary CP levels by 2% to 4% with balancing 10 EAA,or only further supplementation with Ile or Val+Ile to a low protein diet(-4%) reduced the N contents entering the hindgut to various degrees,altered the abundances of N-metabolizing bacteria,and improved the abilities of N utilization.