Comparative effects of enzymatic soybean,fish meal and milk powder in diets on growth performance,immunological parameters,SCFAs production and gut microbiome of weaned pigletsOA

Background: The objective of this study was to evaluate the replacement effects of milk powder(MK) and fish meal(FM) by enzymatic soybean(ESB) in diets on growth performance, immunological parameters, SCFAs production and gut microbiome of weaned piglets.Methods: A total of 128 piglets with initial body weight at 6.95 ± 0.46 kg, were randomly assigned into 4 dietary treatments with 8 replicates per treatment and 4 piglets per replicate for a period of 14 d. Piglets were offered isonitrogenous an...     

N-Acetyl-D-glucosamine improves the intestinal development and nutrient absorption of weaned piglets via regulating the activity of intestinal stem cells

Early weaning in piglets can cause a series of negative effects.This causes serious losses to the livestock industry.N-Acetyl-D-glucosamine(D-GlcNAc)plays an important role in regulating the homeostasis of the intestine.This study aimed to investigate the effects of D-GlcNAc on the growth performance and intestinal function of weaned piglets.Twenty-four weaned piglets([Yorkshire×Landrace]
Duroc,6.58±0.15 kg,n=8)at 21 d old were fed 3 diets supplemented with 0(control),1 and 3 g/kg D-GlcNAc.The intestinal organoid model was used to verify the regulatory mechanism of D-GlcNAc on intestinal epithelial cells.On the whole,supplementation of D-GlcNAc in the piglet diet has no significant effect on the growth performance and diarrhoea of weaned piglets(P>0.05).The apparent digestibility of nutrients and mRNA abundance of nutrient transporters in the 1 g/kg D-GlcNAc group were increased significantly(P<0.05).D-GlcNAc did not affect villus height(VH)and crypt depth(CD)but resulted in a numerically shorter VH and shallower CD,which lead to an increase in ileal VH:CD ratio(P<0.05).Cell shedding rates in the ileum villi increased(P<0.05).The relative length and weight of the small intestine of weaned piglets increased(P<0.05).In vitro studies found that the budding rates of organoids treated with 0.1 mmol/L D-GlcNAc increased on the d 3 and 5(P<0.05).The average budding numbers per budding organoid treated with 0.1 and 10 mmol/L D-GlcNAc increased on d 3(P<0.05).D-GlcNAc upregulated leucine rich repeat containing G protein-coupled receptor 5(Lgr5⁺)and Chromogranin A mRNA abundance in organoids(P<0.05).Mucin 2(Muc2)expression increased when treated with 1 and 10 mmol/L D-GlcNAc(P<0.05).In conclusion,dietary D-GlcNAc cannot improve the growth performance of weaned piglets.However,it can promote the growth and development of the intestinal tract and improve the digestion and absorption capacity of the intestine,which is achieved by affecting the activity of intestinal stem cells.     

Supplementation of a lacto-fermented rapeseed-seaweed blend promotes gut microbial-and gut immune-modulation in weaner piglets

Background:The direct use of medical zinc oxide in feed will be abandoned after 2022 in Europe,leaving an urgent need for substitutes to prevent post-weaning disorders.Results:This study investigated the effect of using rapeseed-seaweed blend(rapeseed meal added two brown macroalgae species Ascophylum nodosum and Saccharina latissima)fermented by lactobacilli(FRS)as feed ingredients in piglet weaning.From d 28 of life to d 85,the piglets were fed one of three different feeding regimens(n=230 each)with inclusion of 0%,2.5% and 5% FRS.In this period,no significant difference of piglet performance was found among the three groups.From a subset of piglets(n=10 from each treatment),blood samples for hematology,biochemistry and immunoglobulin analysis,colon digesta for microbiome analysis,and jejunum and colon tissues for histopathological analyses were collected.The piglets fed with 2.5% FRS manifested alleviated intraepithelial and stromal lymphocytes infiltration in the gut,enhanced colon mucosa barrier relative to the 0% FRS group.The colon microbiota composition was determined using V3 and V1-V8 region 16S rRNA gene amplicon sequencing by Illumina NextSeq and Oxford Nanopore MinION,respectively.The two amplicon sequencing strategies showed high consistency between the detected bacteria.Both sequencing strategies indicated that inclusion of FRS reshaped the colon microbiome of weaned piglets with increased Shannon diversity.Prevotella stercorea was verified by both methods to be more abundant in the piglets supplied with FRS feed,and its abundance was positively correlated with colonic mucosa thickness but negatively correlated with blood concentrations of leucocytes and IgG.Conclusions:FRS supplementation relieved the gut lymphocyte infiltration of the weaned piglets,improved the colon mucosa barrier with altered microbiota composition.Increasing the dietary inclusion of FRS from 2.5% to 5% did not lead to further improvements.     

Administration of Saccharomyces boulardii mafic-1701 improves feed conversion ratio,promotes antioxidant capacity,alleviates intestinal inflammation and modulates gut microbiota in weaned piglets

Background:Probiotics are used as a means to improve animal health and intestinal development.Saccharomyces boulardii is a well-known probiotic;however,few studies have examined the effects of S.boulardii on weaned piglet performance.Therefore,this 28-day study compared the effects of S.boulardii mafic-1701 and aureomycin in diets for weaned piglets on growth performance,antioxidant parameters,inflammation and intestinal microbiota.One hundred and eight piglets,weaned at 28 d of age (8.5±1.1 kg),were randomly divided into the three dietary treatment groups with six pens and six piglets per pen (half male and half female).The dietary treatment groups were as follows:1) basal diet (CON);2) basal diet supplemented with 75 mg/kg aureomycin (ANT);3) basal diet supplemented with 1×10~8CFU/kg S.boulardii mafic-1701 (SB).Results:Compared to CON group,SB group had higher feed efficiency (P0.05) in the last 14 d and lower diarrhea rate (P0.05) over the entire 28 d.Total superoxide dismutase in serum was markedly increased in SB group (P0.05).Moreover,compared with CON group,SB group decreased the levels of pro-inflammatory cytokines interleukin-6 (P0.01) and Tumor necrosis factor-α(P0.05) in jejunum.Supplementation of S.boulardii mafic-1701 increased the abundance of Ruminococcaceae_UCG_009 and Turicibacter (P0.05),whereas the abundance of unclassified_Clostridiaceae_4 was decreased (P0.05).Furthermore,S.boulardii mafic-1701 dministration increased cecal concentration of microbial metabolites,isobutyrate and valerate (P0.05).Conclusions:The improvement in feed conversion ratio,reduction in diarrhea rate in weaned piglets provided diets supplemented with S.boulardii mafic-1701 may be associated with enhanced antioxidant activity,anti-inflammatory responses and improved intestinal microbial ecology.     

Microencapsulated essential oils combined with organic acids improves immune antioxidant capacity and intestinal barrier function as well as modulates the hindgut microbial community in pigletsOA

Background: The objective of this experiment was to evaluate the effect of a combination of microencapsulated essential oils and organic acids(MOA) on growth performance, immuno-antioxidant status, intestinal barrier function and microbial structure of the hindgut in piglets. A total of 120 piglets(Duroc × [Landrace × Yorkshire];weighted 7.66 ± 1.79 kg, weaned at d 28) were randomly selected and allocated to 3 treatments with 4 replicates per group and 10 piglets per replicate according to the i...     

The effect of dietary tryptophan levels on oxidative stress of liver induced by diquat in weaned piglets

Oxidative stress can induce abnormal tryptophan metabolism.The present study was mainly conducted to determine the effect of dietary tryptophan levels on oxidative stress in the liver of weaned pigs challenged by diquat.A total of 36 PIC piglets weaned at 21 days of age were randomly allotted to 1 of 3 diets containing dietary tryptophan levels of 0.18,0.30,and 0.45%for 14 d.On day 8,the piglets were injected intraperitoneally with sterile0.9%NaCI solution or diquat(10 mg/kg body weight).During the first 7 d of trial,increasing dietary tryptophan levels enhanced average daily gain(P=0.09) and average daily feed intake(P=0.08),and decreased the feed efficiency(P<0.05) of piglets.The growth performance was decreased by diquat injection(P<0.05).Diquat injection also decreased the activities of the superoxide dismutase(SOD) and glutathione peroxidase(GPx) in the plasma and liver(P<0.05),increased plasma malondialdehyde(MDA)(P<0.05) and urea nitrogen(P<0.05) concentrations,and enhanced MDA concentration(P =0.09) and tryptophan 2,3-dioxygenase(TDO) activity(P =0.07) in liver of piglets.Increasing dietary tryptophan levels could attenuate the effects of diquat injection on the MDA(P =0.06) concentration and the activities of SOD(P=0.09) and GPx(P=0.05) of the liver,and plasma urea nitrogen(P =0.06) concentration in the piglet.There was a synergistic role for increasing TDO activity in the liver between dietary tryptophan levels and diquat injection(P<0.05).These results suggest that increasing dietary tryptophan levels could attenuate the oxidative stress of the liver in weaned piglets intraperitoneally injected with diquat via enhancing the antioxidant capacity.     

Different dietary protein sources influence growth performance,antioxidant capacity,immunity,fecal microbiota and metabolites in weaned piglets

The inclusion of high-quality proteins are commonly used in swine production.Our research investigated the effects of hydrolyzed wheat protein(HWP),fermented soybean meal(FSBM),and enzyme-treated soybean meal(ESBM)on growth performance,antioxidant capacity,immunity,fecal microbiota and metabolites of weaned piglets.A total of 144 piglets(weaned at 28 d)were allotted to 3 dietary treatments with 6 replicate pens per treatment and 8 piglets per pen.This study included 2 periods:d 0 to14 for phase 1 and d 15 to 28 for phase 2.Dietary treatments contained 15.90%HWP,15.80%FSBM,and 15.10%ESBM in phase 1,and 7.90%HWP,7.80%FSBM,and 7.50%ESBM in phase 2,respectively.The ADG of piglets in ESBM was increased(P<0.05)compared with HWP and FSBM during d 1e28.Compared with HWP and FSBM,ESBM increased(P<0.05)the ferric reducing ability of plasma(FRAP),and the serum level of superoxide dismutase(SOD)in piglets on d 14,as well as increased(P<0.05)the serum FRAP level in piglets on d 28.ESBM decreased(P<0.05)serum levels of DAO and IL-1b in piglets compared with HWP on d 28.ESBM enhanced(P<0.05)the relative abundance of Bacteroidetes,Oscillospiraceae and Christensenellaceae,as well as reduced the relative abundance of Clostridiaceae in the feces compared with HWP and FSBM.The PICRUSt analysis revealed that the number of gene tags related to degradation of valine,leucine and isoleucine,as well as lysine degradation in ESBM were lower(P<0.05)than that in HWP and FSBM.ESBM increased(P<0.05)the fecal butyrate level in piglets compared with FSBM,and ESBM tended to decrease(P=0.076)the fecal cadaverine level.Overall,ESBM had advantages over HWP and FSBM in improving antioxidant status,immune function,fecal bacteria and metabolites for weaned piglets.     

Mechanisms Involved in the Growth Promotion of Weaned Piglets by High-level Zinc Oxide1

Dietary supplementation with high lev- els of zinc oxide （ZnO） is an effective method to prevent diarrhea and promote growth in weaned pig- lets. However, the mechanisms behind these beneficial effects are not well understood. Recent advances in this field indicated that the effects of ZnO on piglet growth are achieved through multiple regulatory path- ways rather than a single pathway. This review focu- ses on recent advances in the effects of high level ZnO on： 1 ） Zn status in weaned piglets; 2 ） intestinal microbe flora regulation; 3 ） intestinal structure and function;4） ion secretion in the intestine epithelium;5） intestinal immunology; and 6） secretion of brain-in- testine peptides. ZnO appears to regulate the intestinal microflora and decreases the release of histamine to prevent diarrhea. ZnO also increases the expression of intestinal insulin-like growth factor-1 （ IGF-1 ） and the IGF-1 receptor to ameliorate intestinal injury associat- ed with weaning, and mediates secretion of brain-gut peptides to stimulate food intake, to promote the growth of piglets. Better understanding of the underly-1 ing mechanisms should inspire us to supplement the diet for weaned piglets with ZnO and investigate new approaches to prevent diarrhea and enhance growth.     

Myokine interleukin-15 expression profile is different in suckling and weaning piglets

Interleukin-15(IL-15) is a cytokine highly expressed in skeletal muscle. The objective of the present study was to investigate the development of muscle IL-15 expression in suckling piglets and in early weaning piglets(day 14) at each level, that is, mRNA, protein, and secretion. Eight litters(eight piglets per litter) of newborn healthy piglets(Large × White × Landrace) with a similar initial weight(1618.0 ± 140.1 g) were chosen and divided into two groups, Group one used suckling piglets that were killed, respectively, at days 1,7,14,21, and group two used early(day 14) weaning piglets that were killed respectively, at days 15, 17, 19, 21. In group one, IL-15 gene expression levels increased significantly(P 0.05) along with increased body weight over time. IL-15 protein expression levels in piglets at day 21 of age were higher(P 0.05) than those in piglets at other ages, and there was no difference(P 0.05)among piglets at other ages. These findings indicated that increased IL-15 mRNA expression did not result in a corresponding increase of its protein expression. In group two, which used early weaning piglets from days 15-19, IL-15 mRNA and protein expression levels increased constantly(P 0.05) and were higher(P 0.05) than those in suckling piglets. Moreover, there was no gain of body weight(P 0.05) compared with suckling piglets at day 14 of age. However, IL-15 protein expression levels in early weaning piglets at day 21 of age dropped significantly(P 0.05) to the levels as suckling piglets at day 21 of age, while body weight increased(P 0.05) markedly to the levels as suckling piglets at day 21 of age. In both groups, the serum IL-15 levels of piglets decreased significantly(P 0.01) over time. Taken together, our results indicate that IL-15 expression differs in suckling piglets and in weaning piglets. It is speculated that IL-15 may play an important role in counteracting the effects of early weaning stress.     

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 of6.60 ± 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% and1.0% 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 dietary Clostridium butyricum supplementation on growth performance,intestinal development,and immune response of weaned piglets challenged with lipopolysaccharide

Background: Weanling pigs, with immature immune system and physiological function, usually experience postweaning diarrhea. This study determined the effects of dietary Clostridium butyricum supplementation on growth performance, diarrhea, and immunity of weaned pigs challenged with lipopolysaccharide(LPS).Methods: In Experiment(Exp.) 1,144 weaned piglets were weaned at 21 d and randomly assigned to six groups,with six replicates per group and four pigs per replicate, receiving a control diet(CON) or diet supplemented with antibiotics(AB) or C. butyricum(CB)(0.1%, 0.2%, 0.4%, or 0.8%), respectively. All diets in Exp. 1 were a highly digestible basal diet, with 3,000 mg/kg zinc oxide supplied in the first 2 wk only. In Exp. 2, 180 piglets were weaned at 21 d and randomly assigned to five groups, with six replicates per group and six pigs per replicate, receiving CON, AB, or CB(0.2%, 0.4%, or 0.6%) diets. The digestibility of diets was lower than those in Exp. 1, and did not include zinc oxide. At 36 d of Exp. 2, 12 piglets were selected from each of the CON and 0.4% CB groups, six piglets were intraperitoneally injected with LPS(50 μg/kg body weight) and the other six piglets with normal saline;animals were killed at 4 h after injection to collect blood, intestine, and digesta samples for biochemical analysis.Results: In Exp. 1, CB and AB diets had no effect on growth performance of piglets. In Exp. 2, 0.4% CB decreased feed-gain ratio(P 0.1), diarrhea score(P 0.05), and increased duodenal, jejunal, and ileal villus height and jejunal villus height/crypt depth(P 0.05). The 0.4% CB decreased the plasma tumor necrosis factor(TNF) α(P 0.05) but increased ileal mucosa IL-10 and TLR2 mRNA expression(P 0.05). Furthermore, 0.4% CB altered the microbial profile, with Bacillus and Ruminococcaceae UGG-003 at genus level and Lactobacillus casei and Parasutterella secunda at species level were higher than CON in colonic content(P 0.05).Conclusions: Dietary C. butyricum supplementation had positive effects on growth of weaned piglets with less digestible diets. There was a tendency to reduce the feed-gain ratio, which could reduce feed costs in pig production. Moreover, C. butyricum decreased post-weaning diarrhea by improving the intestinal morphology,intestinal microflora profile, and immune function.     

Fat deposition deficiency is critical for the high mortality of pre-weanling newborn piglets

Background: The high mortality of pre-weanling piglets is a dominant challenge which severely restricts the development of pig industry. A number of factors including nutrients imbalance and temperature variation during postnatal period of piglets have been reported to closely associated with the high mortality of postnatal piglets.This study aims to find out the relationship between fat deposition and survival of newborn piglets.Results: There were no differences in organ coefficient and bone density between the surviving and dead piglets(P 0.05). The body weight and the fat deposition in the dead piglets were lower than the live individuals(P 0.05).Consistently, the average sizes of white adipocytes in back and abdominal adipose tissues of dead piglets were smaller than the survivals(P 0.05). The protein expression levels of adipocyte differentiation markers PPARγ and C/EBPα in the back and abdominal adipose tissues were lower in dead piglets compared to live piglets. The mRNA expressions of thermogenic markers PGC1α and PRDM16 in adipose tissues were decreased in the dead piglets(P 0.05). The microarray of back fat samples from the surviving and dead piglets were conducted; two down-regulated genes namely AAMDC and CASTOR1 were identified from the dead piglets. According to quantitative real-time PCR(RT-PCR) analysis, the mRNA expression of AAMDC decreased, whereas CASTOR1 expression elevated in the dead piglets compared to the surviving piglets(P 0.05).Conclusions: The fat deposition and adipocyte differentiation in the dead piglets are insufficient compared to the surviving piglets, which may attenuate the thermogenic ability of white adipose tissue(WAT). Our data indicate that fat deposition in newborn piglets is vital to their survival.     

Effects of octacosanol extracted from rice bran on blood hormone levels and gene expressions of glucose transporter protein-4 and adenosine monophosphate protein kinase in weaning piglets

The object of this study was to explore the regulatory mechanism of octacosanol to the body of animals and the effects of octacosanol on blood hormone levels and gene expressions of glucose transporter protein(GLUT-4) and adenosine monophosphate protein kinase(AMPK) in liver and muscle tissue of weaning piglets. A total of 105 crossbred piglets([Yorkshire x Landrace] x Duroc) with an initial BW of5.70 ± 1.41 kg(21 d of age) were used in a 6-wk trial to evaluate the effects of octacosanol and tiamulin supplementation on contents of triiodothyronine(T_3),thyroxine(T_4),growth hormone(GH),glucagon(GU) and adrenaline(AD) in blood and gene expressions of GLUT-4 and AMPK in liver and muscle. Piglets were randomly distributed into 3 dietary treatments on the basis of BW and sex. Each treatment had 7 replicate pens with 5 piglets per pen. Treatments were as followed: control group, tiamulin group and octacosanol group. The results showed that compared with control group and tiamulin group, octacosanol greatly promoted the secretion of T3, GH, GU and AD(P 0.01) and significantly up-regulated the gene expressions of GLUT-4 and AMPK in muscle and liver tissues(P 0.05). There was no significant difference between the control group and tiamulin group in T_3, T_4, GH,GU or AD(P 0.05), Results of the present study has confirmed that octacosanol affects energy metabolism of body by regulating secretion of blood hormones and related gene expression in tissue of weaning piglets, which can reduce stress response and has an impact on performance.     

Effects of galacto-oligosaccharides on growth and gut function of newborn suckling piglets

Background: Most research on galacto-oligosaccharides(GOS) has mainly focused on their prebiotic effects on the hindgut,but their beneficial effects on the small intestine(SI) have received little attention.Since jejunum is the important place to digest and absorb nutrients efficiently,optimal maturation of the jejunum is necessary for maintaining the high growth rate in the neonate.Therefore,this study investigates the effect of the early intervention with GOS on the intestinal development of the jejunum.Methods: A total of 6 litters of neonatal piglets(10 piglets per litter; Duroc × Landrace × Large White) with an average birth weight of 1.55 ± 0.05 kg received 1 of 2 treatments based on their assignment to either the control(CON) group or the GOS(GOS) group in each litter.Piglets in the GOS group were orally administrated 10 mL of a GOS solution(reaching 1 g GOS/kg body weight) per day from the age of 1 to 7 d; the piglets in the CON group were treated with the same dose of physiological saline.All piglets were weaned on d 21.On d 8 and 21 of the experimental trial,1 pig per group from each of the 6 litters was euthanized.Results: The early intervention with GOS increased the average daily gains in the third week(P 0.05).Decreased crypt depth was also observed in the jejunum of the piglets on d 21(P 0.05).The early intervention with GOS increased the jejunal lactase activity on d 8,maltase activity and sucrase activity on d 21(P 0.05).In addition,the early intervention with GOS also facilitated the mRNA expression of Sodium glucose co-transporter 1(SGLT1) on d 8 and the m RNA expression of Glucose transporter type 2(GLUT2) on d 21(P 0.05).It was further determined that GOS up-regulated the m RNA expression of preproglucagon(GCG),insulin-like growth factor 1(IGF-1),insulin-like growth factor 1 receptor(IGF-1 R) and epidermal growth factor(EGF).GOS also up-regulated the protein expression of glucagon-like peptide-2(GLP-2) and EGF in the jejunum of the piglets.Furthermore,it was also found that GOS enhanced the protein expression of ZO-1 and occludin on d 8(P 0.05),as well as increased the mRNA expression of TGF-β and decrease the mRNA expression of IL-12(P 0.05).Conclusions: These results indicate that GOS have a positive effect on piglet growth performance in addition to decreasing the crypt depth and enhancing functional development in jejunum of suckling piglets.     

Effects of Spent Mushroom Substrate of Pleurotus eryngii as Fermentation Bed Padding on Growth Performance,Intestinal Microflora and Immunity of Weaning Piglets

[Objective] The paper was to examine the effects of spent mushroom substrate of Pleurotus eryngii as fermentation bed padding on growth performance, intestinal microflora and immunity of weaning pigs. [Method] A total of 120 weaning piglets(Duroc×Landrace×Yorkshire) with the average initial body weight of(8.0 ±0.5) kg were allocated to five dietary treatments in a randomized complete block design for 42 d, each of which was replicated three times with eight piglets per replicate( half male and half female). The padding for control group was 50% sawdust +50%rice husk; experimental group I, 100% spent mushroom substrate; experimental group II, 15% sawdust +15% rice husk +70% spent mushroom sub-strate; experimental group III, 25% sawdust +25% rice husk +50% spent mushroom substrate; and experimental group IV, 35% sawdust +35% rice husk +30% spent substrate. [Result] Except for experimental group IV, the other three experimental groups had higher average daily gain compared to the control group(P0.05). The average daily feed intake in experimental group I increased obviously compared to the control group( P0.05). Except for experimental group I, the diarrhea rate of weaning piglets in experimental groups II, III and IV significantly decreased compared to the control group(P0.05). The number of lactobacilli and bifidobacteria in colon and cecum in experimental groups I, II and III increased distinctly( P0.05), while the number of Escherichia coli and Salmonella decreased remarkably compared to the control group(P0.05). The positive rates of T and B lymphocytes in peripheral blood of weaning piglets in four experimental groups were significantly higher than that in control group at 21 and42 d post weaning(P0.05). The Ig A content of intestinal mucous in piglets was significantly improved in experimental groups II and III( P0.05).[Conclusion] It enhances the production performance when improving immunity and reducing diarrhea rate of piglets by using spent mushroom substrate of P. eryngii as the fermentation bed padding. Experimental group III(25% sawdust +25% rice husk +50% spent mushroom substrate) is the optimal proportion of spent mushroom substrate.     

Dietary bile acid supplementation in weaned piglets with intrauterine growth retardation improves colonic microbiota,metabolic activity,and epithelial function

Background Intrauterine growth retardation(IUGR) is one of the major constraints in animal production. Our previous study showed that piglets with IUGR are associated with abnormal bile acid(BA) metabolism. This study explored whether dietary BA supplementation could improve growth performance and colonic development, function, microbiota, and metabolites in the normal birth weight(NBW) and IUGR piglets. A total of 48 weaned piglets(24 IUGR and 24 NBW) were allocated to four groups(12 piglets pe...     

Lactobacillus frumenti mediates energy production via fatty acid β-oxidation in the liver of early-weaned piglets

Background: Early-weaning of piglets is often accompanied by severe disorders, especially diarrhea. The gut microbiota and its metabolites play a critical role in the maintenance of the physiologic and metabolic homeostasis of the host. Our previous studies have demonstrated that oral administration of Lactobacillus frumenti improves epithelial barrier functions and confers diarrhea resistance in early-weaned piglets. However,the metabolic response to L. frumenti administration remains unclear. Then, we conducted simultaneous serum and hepatic metabolomic analyses in early-weaned piglets administered by L. frumenti or phosphatebuffered saline(PBS).Results: A total of 100 6-day-old crossbred piglets(Landrace × Yorkshire) were randomly divided into two groups and piglets received PBS(sterile, 2 m L) or L. frumenti(suspension in PBS, 10~8 CFU/m L, 2 m L) by oral administration once per day from 6 to 20 days of age. Piglets were weaned at 21 days of age. Serum and liver samples for metabolomic analyses were collected at 26 days of age. Principal components analysis(PCA)showed that L. frumenti altered metabolism in serum and liver. Numerous correlations(P 0.05) were identified among the serum and liver metabolites that were affected by L. frumenti. Concentrations of guanosine monophosphate(GMP), inosine monophosphate(IMP), and uric acid were higher in serum of L.frumenti administration piglets. Pathway analysis indicated that L. frumenti regulated fatty acid and amino acid metabolism in serum and liver. Concentrations of fatty acid β-oxidation related metabolites in serum(such as3-hydroxybutyrylcarnitine, C4-OH) and liver(such as acetylcarnitine) were increased after L. frumenti administration.Conclusions: Our findings suggest that L. frumenti regulates lipid metabolism and amino acid metabolism in the liver of early-weaned piglets, where it promotes fatty acid β-oxidation and energy production. High serum concentrations of nucleotide intermediates, which may be an alternative strategy to reduce the incidence of diarrhea in early-weaned piglets, were further detected. These findings broaden our understanding of the relationships between the gut microbiota and nutrient metabolism in the early-weaned piglets.     

Effects of Encapsulated Compound Acidifiers on Growth Performance in Weaning Piglets

This study was conducted to study the effects of the addition of encapsulated and non-encapsulated compound acidifiers （in a diet based on corn-soybean meal-extruded soybean） on growth performance and incidence of diarrhea in weaning piglets. Sixty-four 28-day-old, crossbred piglets （Landrace × Large White）, weighing an average of 7.004- 0.10 kg, were randomly assigned to four treatments with four replicates per pen, according to the single-factor design principle. The feeding trial lasted for 35 days. The results showed that, when compared to non-encapsulated acidifiers, encapsulated compound acidifiers not only improved the average daily gain and the feed efficiency （P 〈 0.01）, but also reduced the incidence of diarrhea. However, the addition of encapsulated compound acidifiers in piglet diets had no significant effect on the average daily food intake （P〉0.05）. These results indicated that the encapsulated compound acidifiers enhanced the intestinal adaptation, and subsequently improved the growth performance and reduced the incidence of diarrhea in weaning piglets.     

Effect of dietary supplementation with protease on growth performance,nutrient digestibility,intestinal morphology,digestive enzymes and gene expression of weaned piglets

This study was conducted to investigate the effect of dietary protease supplementation on the growth performance, nutrient digestibility, intestinal morphology, digestive enzymes and gene expression in weaned piglets. A total of 300 weaned piglets(21 days of age Duroc x Large White x Landrace; initial BW = 6.27 ± 0.45 kg) were randomly divided into 5 groups. The 5 diets were: 1) positive control diet(PC), 2) negative control diet(NC), and 3) protease supplementations, which were 100, 200, and 300 mg per kg NC diet. Results indicated that final BW, ADG, ADFI, crude protein digestibility, enzyme activities of stomach pepsin, pancreatic amylase and trypsin, plasma total protein, and intestinal villus height were higher for the PC diet and the supplementations of 200 and 300 mg protease per kg NC diet than for the NC diet(P 0.05). Supplementations of 200 and 300 mg protease per kg NC diet significantly increased the ratio of villus height to crypt depth(VH:CD) of duodenum, jejunum and ileum compared with NC diet(P 0.05). Feed to gain ratio, diarrhea index, blood urea nitrogen, and diamine oxidase were lower for the PC diet and supplementations of 200 and 300 mg protease per kg NC diet than for the NC diet(P 0.05). Piglets fed the PC diet had a higher peptide transporter 1(PepTl) mRNA abundance in duodenum than piglets fed the NC diet(P 0.05), and supplementations of 100, 200 and 300 mg protease per kg NC diet increased the PepTl mRNA abundance in duodenum(P 0.05) comparing with the NC diet. Piglets fed the PC diet had a higher b0,+AT mRNA abundance in jejunum than piglets fed the NC diet(P 0.05), and supplementations of 200 and 300 mg protease per kg NC diet increased the b0,+AT mRNA abundance in jejunum and ileum comparing with the NC diet(P 0.05). In summary, dietary protease supplementation increases growth performance in weaned piglets, which may contribute to the improvement of intestinal development, protein digestibility, nutrient transport efficiency, and health status of piglets when fed low digestible protein sources.