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.

Cysteamine increases expression and activity of H^1-K^+-ATPase of gastric mucosal cells in weaning piglets

AIM: To determine the in vivo andin vivo effects of cysteamine (CS) on expression and activity of H+-K+-ATPase of gastric mucosal cells in weaning piglets.METHODS: Eighteen litters of newborn Xinhuai piglets were employed in the in vivo experiment and allocated to control and treatment groups. From 12 d of age (D12), piglets in control group were fed basal diet, while the treatment group received basal diet supplemented with 120 mg/kg CS. Piglets were weaned on D35 in both groups. Six piglets from each group (n = 6) were slaughtered on D28 (one week before weaning), D35(weaning), D36.5, D38, D42, and D45 (36 h, 72 h,one week and 10 d after weaning), respectively. Semiquantitative RT-PCR was performed todetermine the levels of H+-K+-ATPase mRNA in gastric mucosa. H+-K+-ATPase activity in gastric mucosa homogenate was also determined. Gastric mucosal epithelial cells from piglets through primary cultures were used to further elucidate the effect of CS on expression and activity of H+-K+-ATPase in vivo. Cells were treated for 20 h with 0.001,0.01, and 0.1 mg/mL of CS (n = 4), respectively. The mRNA expression of H+-K+-ATPase and somatostatin (SS)as well as the H+-K+-ATPase activity were determined.RESULTS: in vivo, both mRNA expression and activity of H+-K+-ATPase in gastric mucosa of control group exhibited a trend to increase from D28 to D45, reaching a peak on D45, but did not show significant age differences. Furthermore, neither the mRNA expression nor the activity of H+-K+-ATPase was affected significantly by weaning. CS increased the mRNA expression of H+-K+-ATPase by 73%, 53%, 30% and 39% on D28(P = 0.014), D35 (P = 0.017), D42 (P = 0.013) and D45(P = 0.046), respectively. In accordance with the mRNA expression, H+-K+-ATPase activities were significantly higher in treatment group than in control group on D35(P = 0.043) and D45 (P = 0.040). In vivo, CS exhibited a dose-dependent effect on mRNA expression and activity of H+-K+-ATPase. Both H+-K+-ATPase mRNA expression and activity in gastric mucosal epithelial cells were significantly elevated after 20 h of exposure to the moderate (H+-K+-ATPase expression: P=0.03; H+-K+-ATPase activity: P = 0.014) and high concentrations (H+-K+-ATPase expression: P=0.017; H+-K+-ATPase activity:P = 0.022) of CS. Significant increases in SS mRNA expression were observed to accompany the elevation of H+-K+-ATPase expression and activity induced by the moderate (P = 0.024) and high concentrations (P = 0.022) of CS. Low concentration of CS exerted no effects either on expression and activity of H+-K+-ATPase or on SS mRNA expression in cultured gastric mucosal epithelial cells.CONCLUSION: No significant changes are observed in mRNA expression and activity of H+-K+-ATPase in gastric mucosa of piglets around weaning from D28 to D45. CS increases expression and activity of gastric H+-K+-ATPase in vivo and in vivo. SS is involved in mediating the effect of CS on gastric H+-K+-ATPase expression and activity in weaning piglets.

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.

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.

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.

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.

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.

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.

Research on Mechanism and Application of DUAN-NAI-AN on Controlling Weaned Piglet Diarrhea

[ Objective] The study aimed to explore the function mechanism of microbial ecological agent DUAN-NAI-AN on controlling weaned piglet diarrhea. E Method] DUAN-NAI-AN was given to the weaned piglets by oral administration and its effects on diarrhea rate, growth performance, in- testinal microflora, pH values of different parts of the intestine and intestinal mucosal morphology were observed. [ Result] DUAN-NAI-AN could im- prove the growth performance of weaned piglets by increasing the growth rate and phase weight gain, showing as higher livability, average daily gain and daily feed intake as well as lower diarrhea rate with 19.24% decline by contrast to the control. In addition, DUAN-NAI-AN could keep the intestinal mucosal mechanical barrier and normal digestive function by strengthening intestinal resistance and thus enhance the intestinal mucosal im- mune level. It could also decrease the proportion of potential pathogens and their toxicity effects inside the intestine to help the piglets transfer to and then maintain the dynamic balance of intestinal microflora in a very short period, and it also showed a trend of decreasing the pH value of piglet in- testinal contents. [ Conclusion] DUAN-NAI-AN is an effective microbial ecological agent for the control of weaned piglet diarrhea.

Study on Application of Microbial Ecological Agents, Replacements for Antibiotics, in Weaned Piglet Production

In order to investigate the appIication effects of microbial ecoIogical agents as repIacements for antibiotics in weaned pigIets, a total of 120 28 d oId healthy Duroc ＆#215;Landrace ＆#215;Large White weaned pigIets with simiIar bogy weights and body fats and cIose birth dates were seIected. They were randomIy divided into three groups, incIuding controI group （CK）, antibiotic group （A） and microbial ecoIogical agent group （MEA）. The growth performance, health status and economic benefits of the weaned pigIets were measured. The resuIts showed that the A and MEA groups couId better enhance the immunity of weaned pigIets and improve the economic benefits in the whoIe experimental period compared to the CK group （P〈0.01）. How-ever, there were no significant differences in pigIet immunity and economic benefits between the A and MEA groups （P〉0.05）. It is indicated that the Rujunbao, a mi-crobial ecoIogical agent, can be promoted in weaned pigIet production as a repIace-ment for antibiotic.

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.

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.