Gut Bacterial and Lactobacilli Communities of Weaning Piglets in Response to Mannan Oligosaccharide and Sugar Beet Pulp In vitro Fermentation

Microbiota in the gastrointestinal tract （GIT） of piglets during weaning transition can experience a sharp change which could result in growth reduction and diarrhea of weaned piglets. Dietary manipulations can play an important role in attenuating such changes caused by weaning stress. Therefore, ileal and colonic contents of weaned piglets were used as inocula, mannan oligosaccharide （MOS） or sugar beet pulp （SBP） was supplied as single energy sources to investigate effects of MOS or SBP on the shifts of gastro-intestinal microflora and lactobacilli populations. The universal bacteria- and lactobacilli-specific PCR/denaturing gradient gel electrophoresis （DGGE）, cloning and sequencing techniques were used. DGGE profiles of the universal bacteria showed that great changes were found in the position, numbers and intensity of dominant bands after fermentation. The similarity of bacterial community between ileum and colon was increased to 85-97% by MOS or SBP treatment after fermentation from the similarity with 20% before fermentation. MOS treatment significantly increased the bacterial diversity and band number in both ileal and colonic fermentation （P〈0.05）. SBP treatment significantly increased the bacterial diversity and band number in colon （P〈0.05）. It implies that some species were enriched by the addition of MOS or SBP to increase the similarity and diversity of bacterial community in weaned piglets. Five specific bands appearing in MOS or SBP treatment group after fermentation were cloned and sequenced, the changes of species related to Prevotella and Ruminococcus were observed. Two bands related to uncultured bacterium with 98% similarity were detected by MOS or SBP treatment. However, there were no effects on the similarity, diversity index and lactobacilli species revealed by MOS or SBP treatment. These results imply that MOS or SBP could have beneficial effects on the weaning piglets by stablizing microbiota in the GIT microflora.

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 （DurocxLandracexYorkshire） 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 （P〈0.05）. The average daily feed intake in experimental group I increased obviously compared to the control group（P〈0.05）. 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（P〈0.05）. The number of lactobacilli and bifidobacteria in colon and cecum in experimental groups I, II and III increased distinctly （P〈 0.05）, while the number of Escherichia coli and Salmonella decreased remarkably compared to the control group （P〈0.05）. 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 and 42 d post weaning （P〈0.05）. The IgA content of intestinal mucous in piglets was significantly improved in experimental groups II and III （P〈0.05）. [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.

Effect of Fermentation Bed with Spent Mushroom Substrate of Pleurotus eryngii on Weaning Piglets

[Objective] The paper was to investigate effects on fermentation bed temperature,growth performance,diarrhea rate and digestive en-zyme activity of weaning piglets by using spent mushroom substrate of Pleurotus eryngii as padding.[Method] A total of 120 weaning piglets（Duroc × Landrace ×Yorkshire） with 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,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 substrate）;experimental group Ⅲ（25% sawdust ＋25% rice husk ＋50% spent mushroom substrate）;experimental group Ⅳ（35% sawdust ＋35% rice husk ＋30% spent substrate）.[Result] There was no significant difference in surface temperature of fermentation bed between experimental groups and control group（P〉0.05）.Compared with the control group,the temperature under 20 cm of fermentation bed in ex-perimental groups I,Ⅱ and Ⅲ increased significantly（P〈0.05）.Except for experimental group Ⅳ,other three experimental groups had higher aver-age daily gain（P〈0.05） and experimental group Ⅰ had higher average daily feed intake（P〈0.05） compared to the control group.The diarrhea rate and mortality of weaning piglets in experimental groups Ⅱ,Ⅲ and Ⅳ were significantly decreased compared with the control group（P〈0.05）.Compared with the control group,other three experimental groups had higher digestive enzyme activity in duodenal contents except for experimental group Ⅳ（P〈0.05）.[Conclusion] Spent mushroom substrate of P.eryngii can be used as fermentation bed padding,and the optimal proportion was experimental group Ⅲ.

Effects of Microencapsulated Compound Acidifier on Acidity and Development of Gastrointestinal Tract in Weaning Piglets

The effects of different types of compound acidifiers （encapsulated and non-encapsulated） in maize-soybean basic diets on acidity and development of the gastrointestinal tract in weaning piglets were investigated in this study. 64 28-day-old weaned Landrace x Yorkshire hybrid piglets with average weight of （7.00 ±0.10） kg were selected and grouped into four treatments with four pigs （ half boars and half sows） in each repeat of four repeats in each treatment based on single-factor test design principles, and the pre-test period was 3 days but the test period was 35 days. The results showed that compared with acid-free diet group, encapsulated compound acidifier could reduce pH of stomach and intestinal in weaning piglets significantly （P 〈 0.01 ）, while Test group 1 could also increase the relative weight of stomach and intestinal in piglets significantly （P 〈 0.05 ）. Compared with non-encapsulated acidifier, encapsulated compound acidifier could greatly decrease pH in jejunum and ileum of weaning piglets （ P 〈 0.05） or relative weight of stomach in piglets （ P〈0.05）, while Test group 1 could also enhance the relative weight of intestinal in piglets significantly （ P 〈0.01 ）. In addition, encapsulated compound acidifiers significantly increased the ratio between the villus height and crypt depth of jejunum （ P 〈0.01 ）. Accordingly, the microencapsulated compound acidifier in diets of weaning piglets can promote the development of gastrointestinal tracts for piglets by reducing pH of gastrointestinal tracts.

Dietary supplementation of benzoic acid and essential oils combination enhances intestinal resilience against LPS stimulation in weaned piglets

Background The benefits of combining benzoic acid and essential oils(BAO)to mitigate intestinal impairment during the weaning process have been well established,while the detailed underlying mechanism has not been fully elucidated.Previous research has primarily focused on the reparative effects of BAO on intestinal injury,while neglecting its potential in enhancing intestinal stress resistance.Methods In this study,we investigated the pre-protective effect of BAO against LPS-induced stress using a modified experimental procedure.Piglets were pre-supplemented with BAO for 14 d,followed by a challenge with LPS or saline to collect blood and intestinal samples.Results Our findings demonstrated that BAO supplementation led to significant improvements in piglets’final weight,average daily gain,and feed intake/body gain ratio.Additionally,BAO supplementation positively influenced the composition of intestinal microbiota,increasing beneficial Actinobacteriota and Alloprevotella while reducing harmful Desulfobacterota,Prevotella and Oscillospira.Furthermore,BAO supplementation effectively mitigated oxidative disturbances and inflammatory responses induced by acute LPS challenge.This was evidenced by elevated levels of T-AOC,SOD,and GSH,as well as decreased levels of MDA,TNF-α,and IL-6 in the plasma.Moreover,piglets subjected to LPS challenge and pre-supplemented with BAO exhibited significant improvements in intestinal morphological structure and enhanced integrity,as indicated by restored expression levels of Occludin and Claudin-1 compared to the non-supplemented counterparts.Further analysis revealed that BAO supplementation enhanced the jejunal antioxidative capacity by increasing GSH-Px levels and decreasing MDA levels under the LPS challenge and stimulated the activation of the Nrf2 signaling pathway.Additionally,the reduction of TLR4/NF-κB/MAPK signaling pathways activation and proinflammatory factor were also observed in the jejunal of those piglets fed with BAO.Conclusions In summary,our study demonstrates that pre-supplementation of BAO enhances the anti-stress capacity of weaned piglets by improving intestinal microbiota composition,reinforcing the intestinal barrier,and enhancing antioxidative and anti-inflammatory capabilities.These effects are closely associated with the activation of Nrf2 and TLR4/NF-κB/MAPK signaling pathways.

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（T3）,thyroxine（T4）,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 T3, T4, 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.

Oral administration of dibutyryl adenosine cyclophosphate improved growth performance in weaning piglets by enhancing lipid fatty acids metabolism

Dibutyryl adenosine cyclophosphate(dbc AMP-Ca), an analog of cyclic adenosine monophosphate(c AMP), plays greater roles in regulating physiological activities and energy metabolism than c AMP. The aim of this study was to investigate the effect of oral administration of dbc AMP-Ca on growth performance and fatty acids metabolism in weaning piglets. A total of 14 early weaning piglets(7 ± 1 d of age,3.31 ± 0.09 kg, Landrace ? Large White ? Duroc) were randomly divided into 2 groups: control group and dbc AMP-Ca group, and the piglets received 7 m L of 0.9% Na Cl or 1.5 mg dbc AMP-Ca dissolved in 7 m L of 0.9% Na Cl per day for 10 d, respectively. The results showed that the average daily gain(ADG)increased by 109.17%(P < 0.05) in the dbc AMP-Ca group compared with the control group. Besides,dbc AMP-Ca significantly decreased blood high density lipoprotein cholesterol(HDLC) concentration(P < 0.05) and significantly increased blood low density lipoprotein cholesterol(LDLC) concentration(P < 0.05) compared with the control group. Further, liver C18:2 n6 t content significantly increased in dbc AMP-Ca group(P < 0.05) compared with the control group. With the increase of C18:2 n6 t content,the m RNA expression levels of peroxisome proliferator-activated receptor a(PPARa) and hormone sensitive glycerol three lipase(HSL), of which genes are related to lipid metabolism, were also significantly increased(P < 0.05 or P < 0.01). All of the results indicated that dbc AMP-Ca improved the ADG, which was probably done by regulating fatty acids metabolism in the liver of weaning piglets.

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.

Changes of the glutathione redox system during the weaning transition in piglets, in relation to small intestinal morphology and barrier function

Background: Weaning is known to result in barrier dysfunction and villus atrophy in the immediate post-weaning phase, and the magnitude of these responses is hypothesized to correlate with changes in the glutathione(GSH)redox system. Therefore, these parameters were simultaneously measured throughout the weaning phase, in piglets differing in birth weight category and weaning age, as these pre-weaning factors are important determinants for the weaning transition. Low birth weight(LBW) and normal birth weight(NBW) littermates were assigned to one of three weaning treatments;i.e. weaning at 3 weeks of age(3 w), weaning at 4 weeks of age(4 w) and removal from the sow at 3 d of age and fed a milk replacer until weaning at 3 weeks of age(3 d3 w). For each of these treatments, six LBW and six NBW piglets were euthanized at 0, 2, 5, 12 or 28 d post-weaning piglets, adding up 180 piglets.Results: Weaning increased the glutathione peroxidase activity on d 5 post-weaning in plasma, and duodenal and jejunal mucosa. Small intestinal glutathione-S-transferase activity gradually increased until d 12 post-weaning, and this was combined with a progressive rise of mucosal GSH up till d 12 post-weaning. Oxidation of the GSH redox status(GSH/GSSG Eh) was only observed in the small intestinal mucosa of 3 d3 w weaned piglets at d 5 postweaning. These piglets also demonstrated increased fluorescein isothiocyanate dextran(FD4) and horseradish peroxidase fluxes in the duodenum and distal jejunum during the experiment, and specifically demonstrated increased FD4 fluxes at d 2 to d 5 post-weaning. On the other hand, profound villus atrophy was observed during the weaning transition for all weaning treatments. Finally, LBW and NBW piglets did not demonstrate notable differences in GSH redox status, small intestinal barrier function and histo-morphology throughout the experiment.Conclusion: Although moderate changes in the GSH redox system were observed upon weaning, the GSH redox status remained at a steady state level in 3 w and 4 w weaned piglets and was therefore not associated with weaning induced villus atrophy. Conversely, 3 d3 w weaned piglets demonstrated GSH redox imbalance in the small intestinal mucosa, and this co-occurred with a temporal malfunction of their intestinal barrier function.

Developmental changes in intercellular junctions and Kv channels in the intestine of piglets during the suckling and post-weaning periods

Background： The intestinal epithelium is an important barrier that depends on a complex mixture of proteins and these proteins comprise different intercellular junctions. The purpose of this study was to investigate the postnatal and developmental changes in morphology, intercellular junctions and voltage-gated potassium（Kv） channels in the intestine of piglets during the suckling and post-weaning periods.Results： Samples of the small intestine were obtained from 1-, 7-, 14-, and 21-d-old suckling piglets and piglets on d 1, 3, 5, and 7 after weaning at 14 d of age. The results showed that the percentage of proliferating cell nuclear antigen（PCNA）-positive cells and alkaline phosphatase（AKP） activity, as well as the abundances of E-cadherin,occludin, and Kv1.5 m RNA and claudin-1, claudin-3, and occludin protein in the jejunum were increased from d 1to d 21 during the suckling period（P 〈 0.05）. Weaning induced decreases in the percentage of PCNA-positive cells,AKP activity and the abundances of E-cadherin, occludin and zonula occludens（ZO）-1 m RNA or protein in the jejunum on d 1, 3 and 5 post-weaning（P 〈 0.05）. There were lower abundances of E-cadherin, occludin and ZO-1m RNA as well as claudin-1, claudin-3 and ZO-1 protein in the jejunum of weanling piglets than in 21-d-old suckling piglets（P 〈 0.05）. The abundances of E-cadherin, occludin, ZO-1 and integrin m RNA were positively related to the percentage of PCNA-positive cells.Conclusion： Weaning at 14 d of age induced damage to the intestinal morphology and barrier. While there was an adaptive restoration on d 7 post-weaning, the measured values did not return to the pre-weaning levels, which reflected the impairment of intercellular junctions and Kv channels.

The developmental changes in intestinal epithelial cell proliferation,differentiation,and shedding in weaning piglets

Intestinal epithelial homeostasis plays an important role in intestinal morphology and function.However,the developmental changes in intestinal epithelial cell turnover in piglets during early weaning are unknown so far.Thus,the aim of this work was to detect changes in piglet gut development from weaning to post-weaning d 14.Accordingly,40 piglets were used in the present study,and 8 piglets were randomly selected for sampling at d 0,1,3,7 and 14 post-weaning,respectively.The results showed that weaning stress significantly affected small intestinal morphological architecture,and this impact was the worst on d 3,and then returned to normal on d 14.Furthermore,the number of the marker of proliferation Ki-67(Ki67)positive cells was decreased on d 1 and 3,and then recovered on d 14(P<0.001).Also,weaning strikingly increased jejunal epithelial cell shedding on d 1 to 7 compared on d 0(P<0.05).Moreover,weaning remarkably affected the number of small intestinal enterocytes,goblets and endocrine cells(P<0.05),and there were also significant differences in genes expression related to proliferation and differentiation(P<0.05).Additionally,the mechanistic target of rapamycin(mTOR)phosphorylation level was higher on d 3(P<0.05).However,the Wingless/Int1(WNT)/b-catenin pathway was not influenced by post-weaning days.Taken together,weaning induced noteworthy changes in intestinal epithelial cell proliferation,differentiation and shedding,and the mTOR signaling pathway was involved in this process.Our findings provide a cellular mechanism for intestinal developmental changes during weaning periods.This may provide nutritionists with better insight into designing efficient in-feed alternatives for preventing the unfavorable gut development in weaning piglets.

Effects of Weaning on Immunity and Nutrition in Piglets

The number of birth per year was an important indicator of the sow＇s productivity and it was related to the duration of breasffeeding. Weaning had been shown to be a stressful period. The weaning age had declined over time in order to increase sow productivity and the fact that weaning under modern-day commercial conditions inflicted stress （environmental, nutritional and psychological/social） on pigs and associated with marked changes in gastrointestinal tract （GIT） physiology, microbiology and immunology. However, the early weaning resulted in post-weaning diarrhea, mainly related to intestinal dysbiosis during this rapid adaptation to the new diet. The environment and feed had influence on physiology, gut morphology, immune system and diseases of weaned piglets.

Dietary fibers with low hydration properties exacerbate diarrhea and impair intestinal health and nutrient digestibility in weaned piglets

Background:This study aimed to investigate the hydration properties of different-source fibrous materials by com-paring their water-binding capacity(WBC),water swelling capacity(WSC),viscosity,and in vivo effects of selected samples on growth performance,nutrient digestibility,diarrhea,and intestinal health in weaned piglets.Methods:A total of 13 commercially available fibrous materials were first compared in chemical composition and in vitro hydration property.Subsequently,40 weaned piglets were randomized to five experimental dietary groups(8 piglets per group):control diet(a basal diet without dietary fiber,CON),basal diet supplemented with 5%microcrys-talline cellulose(MCC),5%wheat bran(WB),5%Moringa oleifera leaf powder(MOLP),or 5%sugar beet pulp(SBP),fol-lowed by analyzing their growth performance and diarrhea rate in a 28-d experiment.After the feeding experiment,anaesthetized piglets were killed,and their intestinal and colon content or plasma samples were analyzed in nutrient digestibility,intestinal morphology,intestinal barrier,short-chain fatty acids(SCFAs),and bacterial population.Results:In vitro studies showed low hydration properties for WB and MCC,while medium hydration properties for MOLP and SBP.In vivo studies indicated that compared with medium hydration property groups,low hydration prop-erty groups showed(1)exacerbated diarrhea,impaired intestinal health,and reduced apparent fecal digestibility of dry matter,gross energy,acid detergent fiber,and neutral detergent fiber;(2)decreased SCFAs concentration and rela-tive levels of Lactobacillus and Bifidobacterium,but increased levels of Escherichia coli and Brachyspira hyodysenteriae in colon contents.Additionally,SBP showed optimal performance in reducing diarrhea and increasing SCFAs produc-tion.Correlation analysis revealed a positive correlation of fiber hydration properties with in vitro SCFAs production,and diarrhea index and nutrient digestibility were negatively and positively correlated with SCFAs levels in the colon contents of weaned piglets,respectively.Conclusions:Different-source dietary fibers varied in their hydration properties and impacts on diarrhea,microbial composition and SCFAs production in weaned piglets.WB and MCC could exacerbate diarrhea and impair nutrient digestibility,probably because their low hydration properties were detrimental to gut microbial homeostasis and fermentation.Our findings provide new ideas for rational use of fiber resources in weaned piglets.

Intermittent suckling with or without comingling of non-littermate piglets before weaning improves piglet performance in the immediate post-weaning period when compared with conventional weaning

Background： In this experiment, intermittent suckling（IS） with or without the co-mingling（Co M） of piglets was studied as a method to stimulate solid feed intake and reduce post-weaning stress.Methods： Three weaning regimes using 30 multiparous sows were compared：（1） conventional weaning（CW）（n = 10 litters）, where piglets had continuous access to the sow until weaning（d 0, farrowing = d-25 relative to weaning）;（2） intermittent suckling（IS）（n = 10 litters）, where piglets were separated from the sow for 8 h/d starting at d-7（relative to weaning）; and（3） intermittent suckling with co-mingling（ISCo）（n = 10 litters） where IS started at d-7 and two litters were housed together during separation and then returned to their original sow. Ad libitum creep feed was available from d-17. At weaning pigs were housed in pens of 11 pigs, 27 pens in total. The ISCo treatment was divided in half to examine effects of different mixing strategies after weaning. Half of the ISCo litters were kept in familiar groups（ISCo F, familiar, n = 4） and the other half were mixed within treatment resulting in groups of unfamiliar pigs（ISCo NF, not familiar, n = 5）, the same as IS（n = 9） and CW（n = 9） treatments.Results： The ISCo piglets ate more creep feed in the week before weaning（P 〈 0.01）, but also showed more aggressive and manipulative behaviour on first day of Co M compared with CW piglets（P 〈 0.05）. IS with or without Co M increased exploratory and play behaviour on the first day of treatment intervention（P 〈 0.001） and increased sleeping behaviour on the last day of treatment intervention compared with CW（P 〈 0.001）. Mixing strategy at weaning had an effect on performance data with the highest growth and feed intake seen in ISCo F pigs 2 to 8 d after weaning（P 〈0.001）. IS and ISCo NF pigs also grew faster and ate more than CW pigs 2 to 8 d after weaning（P 〈 0.001）. Post-weaning injury scores suggested reduced aggression in ISCo as evidenced by reduced redness（skin irritation）（P 〈 0.05）, and a tendency for ISCo to have less scratches than CW（P 〈 0.1）. The IS pigs slept the most and displayed less manipulative behaviours on the day of weaning and plasma haptoglobin levels remained low in IS pigs after weaning（P ≤ 0.01）.Conclusions： Both intermittent suckling techniques improved production indices in the immediate post-weaning period. However, the addition of co-mingling before weaning in combination with grouping familiar pigs together after weaning improved performance in an additive manner.

Effects of lactic acid bacteria-fermented formula milk supplementation on ileal microbiota,transcriptomic profile,and mucosal immunity in weaned piglets

Background:Lactic acid bacteria(LAB)participating in milk fermentation naturally release and enrich the fermented dairy product with a broad range of bioactive metabolites,which has numerous roles in the intestinal health-promot-ing of the consumer.However,information is lacking regarding the application prospect of LAB fermented milk in the animal industry.This study investigated the effects of lactic acid bacteria-fermented formula milk(LFM)on the growth performance,intestinal immunity,microbiota composition,and transcriptomic responses in weaned piglets.A total of 24 male weaned piglets were randomly divided into the control(CON)and LFM groups.Each group consisted of 6 replicates(cages)with 2 piglets per cage.Each piglet in the LFM group were supplemented with 80 mL LFM three times a day,while the CON group was treated with the same amount of drinking water.Results:LFM significantly increased the average daily gain of piglets over the entire 14 d(P<0.01)and the average daily feed intake from 7 to 14 d(P<0.05).Compared to the CON group,ileal goblet cell count,villus-crypt ratio,sIgA,and lactate concentrations in the LFM group were significantly increased(P<0.05).Transcriptomic analysis of ileal mucosa identified 487 differentially expressed genes(DEGs)between two groups.Especially,DEGs involved in the intestinal immune network for IgA production pathways,such as polymeric immunoglobulin receptor(PIGR),were significantly up-regulated(P<0.01)by LFM supplementation.Moreover,trefoil factor 2(TFF2)in the LFM group,one of the DEGs involved in the secretory function of goblet cells,was also significantly up-regulated(P<0.01).Sequenc-ing of the 16S rRNA gene of microbiota demonstrated that LFM led to selective enrichment of lactate-producing and short-chain fatty acid(SCFA)-producing bacteria in the ileum,such as an increase in the relative abundance of Entero-coccus(P=0.09)and Acetitomaculum(P<0.05).Conclusions:LFM can improve intestinal health and immune tolerance,thus enhancing the growth performance of weaned piglets.The changes in microbiota and metabolites induced by LFM might mediate the regulation of the secretory function of goblet cells.

Influence of Sows Farrowing Performance on Growth of 21-Day-Old Weaned Piglets and Their Correlation Research

[ Objective ] To study the influence of sows farrowing performance on the growth of 21-day-old weaned piglets and their correlation. [ Methods ] A total of 1 350 Duroc x Landrace Yorkshire piglets produced by 2-6 fetal Landrace x Yorkshire sows from 118 litters within a month were selected to be the test objects. All the newborn piglets were lactated by their parent sows. The test groups were divided according to different numbers （6 - 17） of live birth. The variance analysis were conducted on birth weight, litter weight at birth, number of 21-day-old weaning piglets, weaning weight, weaninl2g weight of litter, weaning survival rate and relative individual weight gain among different weeks. [ Results] Sows farrowing performance had significant influence on the growth performance of 21- day-old piglets. However, the influences among different traits varied, some were even on the contrary. With the increase of the number of live birth, the birth weight, weaning weight of litter and weaning survival rate showed a decline trend. And when the number of live birth was equal or more than 14, the weaning sur- vival rate dropped to below 90% （P 〈 0.01 ） ; when the number of live birth was 13, the litter weight at birth and weaning weight of litter reached the peak. What- ever the number of live birth increased or decreased, the weaning weight showed a regular decline trend. [ Conclusions] When the number of live birth changed from 11 to 13, the maximum values of the economic indicator （weaning weight of litter） and the technical specifications （weaning survival rate） were achieved.

Dietary garcinol supplementation improves diarrhea and intestinal barrier function associated with its modulation of gut microbiota in weaned piglets

Background:The effects of dietary garcinol on diarrhea and intestinal barrier function associated with its modulation of gut microbiota in weaned piglets were investigated.Method:One hundred forty four weaned piglets(Duroc×Yorkshire×Landrace)from 16 pens(9 piglets per pen)were randomly divided into four treatment groups:controls(CON)or those supplemented with 200 mg/kg(LOW),400 mg/kg(MID),or 600 mg/kg(HIGH)diet garcinol.After 14-day trial,three piglets per pen were chosen to collect plasma,intestinal tissue and colonic digesta samples.Results:We demonstrated for the first time that garcinol promoted growth performance,as increased average daily feed intake(ADFI)and decreased feed/gain ratio(F/G);and reduced diarrhea incidence(P<0.05);and strengthened antioxidant capacity,as an increased antioxidative index(P<0.05).Additionally,garcinol ameliorated intestinal barrier dysfunction,as an increased villus height to crypt depth ratio,increased zonula occludens protein 1(ZO-1),occludin and claudin-1 expression in the jejunum and ileum(P<0.05),and decreased intestinal permeability(P<0.05);and reduced inflammation,as decreased cytokine interleukin(IL)-6,IL-10,IL-1βand tumor necrosis factor-α(TNF-α)levels in the mucosa of the jejunum and ileum,and NF-κB p65 translocation(P<0.05).Moreover,garcinol inhibited the growth of most harmful bacteria in the gut,especially Escherichia coli,and increased the growth of the beneficial bacteria Lactobacillus.Conclusion:This work provides a fundamental basis for the future development of garcinol-functional food use for improving diarrhea and intestinal barrier function in weaned piglets and for understanding the biological effects of garcinol and its potential as a functional feed additive.

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 0A5% for 14 d. On day 8, the piglets were injected intraperitoneally with sterile 0.9% 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.

Effect of Dietary Supplementation with Hydrolyzed Wheat Gluten on Growth Performance, Cell Immunity and Serum Biochemical Indices of Weaned Piglets (Sus scrofa)

To investigate the effects of dietary supplementation with hydrolyzed wheat gluten （HWG） on growth performance, cell immunity and serum biochemical indices of weaned piglets, 160 crossed （Large White×andrace） and weaned piglets were randomly divided into 4 treatments with 4 replicates of 10 piglets each. The piglets in each treatment were fed an experimental diet containing either 0 g kg-1 HWG （control group）, 30 g kg-1 HWG （3% HWG group）, 50 g kg-1 HWG （5% HWG group）, or 2.5 g kg-1 glycyl-L-glutamine （0.25% Gly-Gln group）. The results showed that the diarrhea rates in 3% HWG and 5% HWG groups were significantly lower than in control group from d 1 to 14 （P〈0.05）, while the average daily gain （ADG） in each of two groups was increased （P〉0.05）. When compared with control group, dietary supplementation with 3% HWG increased the ratio of CD4＋：CD8＋ and the ratio of serum albumin and globulin concentrations （A：G） on d 14 and 28, as well as the proliferation of T- and B-lymphocytes （P〉0.05） on d 28. In addition, on d 14 and 28, the A：G ratio in 5% HWG group was significantly higher than in control group （P〈0.05）, while the ratio of CD4＋：CD8＋ increased slightly （P〉0.05）. Interestingly, 0.25% Gly-Gln group had higher proportion of CD3＋ （P〉0.05） and CD4＋ （P〈0.05） on d 14 than control group, but growth performances of 0.25% Gly-Gln group were negatively affected at all experiment stages. These results suggested that HWG might improve the growth performance of piglets by strengthening cell immunity and decreasing the occurrence of diarrhea during the prophase after weaning.

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 1×108 CFU/kg S.boulardii mafic-1701(SB).Results:Compared to CON group,SB group had higher feed efficiency(P<0.05)in the last 14 d and lower diarrhea rate(P<0.05)over the entire 28 d.Total superoxide dismutase in serum was markedly increased in SB group(P<0.05).Moreover,compared with CON group,SB group decreased the levels of pro-inflammatory cytokines interleukin-6(P<0.01)and Tumor necrosis factor-α(P<0.05)in jejunum.Supplementation of S.boulardii mafic-1701 increased the abundance of Ruminococcaceae_UCG_009 and Turicibacter(P<0.05),whereas the abundance of unclassified_Clostridiaceae_4 was decreased(P<0.05).Furthermore,S.boulardii mafic-1701 administration increased cecal concentration of microbial metabolites,isobutyrate and valerate(P<0.05).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,antiinflammatory responses and improved intestinal microbial ecology.