Development of small intestinal barrier function and underlying mechanism in Chinese indigenous and Duroc piglets during suckling and weaning periods

This study explored the developmental changes in small intestinal barrier function and the potential regulatory roles of intestinal microbiota and metabolites in different breeds of piglets during suckling and weaning periods.Taoyuan black(TB),Xiangcun black(XB),and Duroc(DR)piglets(10 litters per breed;half male and half female)were selected for sampling to evaluate the intestinal barrier-related indexes and intestinal microbiota and metabolites at 1,10,21(weaned),and 24(3 d after weaning)d old.The results showed that weaning led to severe shedding of small intestinal microvilli and sparse microvilli arrangement.D-lactate level in the ileum of TB and XB piglets during suckling and weaning periods was lower(P<0.01)than that of DR piglets,as well as the ileal diamine oxidase level at 1 d old.The expression level of mucin 1 was higher(P<0.05)in the ileum of TB and XB piglets than that of DR piglets,and it was the highest in the ileum of TB piglets at 21 d old.The expression levels of mucin 2 and mucin 13 were higher(P<0.10)in TB and XB piglets than those of DR piglets at 21 d old,whereas mucin2 and mucin 13 in the ileum of TB and XB piglets were higher(P<0.05)than those of DR piglets at 24 d old.TB and XB piglets had a lower relative abundance of Escherichia_Shigella at 21 and 24 d old,but they had higher Streptococcus at 1 and 24 d old than DR piglets(P<0.01).Differential metabolites between the three breeds of piglets were mainly related to oxidative phosphorylation,steroid biosynthesis,and bile acid synthesis.Collectively,these findings suggest that different pig breeds present differences in the development of the small intestinal barrier function.Compared with DR piglets,TB and XB piglets had higher intestinal permeability during the suckling period and a stronger intestinal mechanical barrier after weaning.Moreover,intestinal microbiota and metabolites are the key factors for developing small intestinal barrier functions in different breeds of piglets.

Comparison of the protective effects of resveratrol and pterostilbene against intestinal damage and redox imbalance in weanling piglets

Background: Evidence indicates that early weaning predisposes piglets to intestinal oxidative stress and increases the risk of intestinal dysfunction;however, there are minimal satisfactory treatment strategies for these conditions.This study investigated the potential of resveratrol and its analog, pterostilbene, as antioxidant protectants for regulating intestinal morphology, barrier function, and redox status among weanling piglets.Methods: A total of 144 piglets were selected at 21 days of age and randomly allocated into one of four treatment groups, each of which included six replicates. Piglets in a sow-reared control group were suckling normally between ages 21 and 28 days, while those in weaned groups were fed a basal diet, supplemented with either 300 mg/kg of resveratrol or with 300 mg/kg of pterostilbene. Parameters associated with intestinal injury and redox status were analyzed at the end of the feeding trial.Results: Early weaning disrupted the intestinal function of young piglets, with evidence of increased diamine oxidase activity and D-lactate content in the plasma, shorter villi, an imbalance between cell proliferation and apoptosis, an impaired antioxidant defense system, and severe oxidative damage in the jejunum relative to suckling piglets. Feeding piglets with a resveratrol-supplemented diet partially increased villus height(P = 0.056) and tended to diminish apoptotic cell numbers(P = 0.084) in the jejunum compared with those fed a basal diet. Similarly, these beneficial effects were observed in the pterostilbene-fed piglets. Pterostilbene improved the feed efficiency of weanling piglets between the ages of 21 and 28 days;it also resulted in diminished plasma diamine oxidase activity and D-lactate content relative to untreated weaned piglets(P < 0.05). Notably, pterostilbene restored jejunal antioxidant capacity, an effect that was nearly absent in the resveratrol-fed piglets. Pterostilbene reduced the malondialdehyde and 8-hydroxy-2′-deoxyguanosine contents of jejunal mucosa possibly through its regulatory role in facilitating the nuclear translocation of nuclear factor erythroid-2-related factor 2 and the expression levels of NAD(P)H quinone dehydrogenase 1 and superoxide dismutase 2(P < 0.05).Conclusions: The results indicate that pterostilbene may be more effective than its parent compound in alleviating early weaning-induced intestinal damage and redox imbalance among young piglets.

Rumen microbiota-host transcriptome interaction mediates the protective effects of trans-10,cis-12 CLA on facilitating weaning transition of lambs

Developing alternatives to antibiotics for prevention of gastrointestinal dysbiosis in early-weaning farmed animals is urgently needed.This study was to explore the potential effects of trans-10,cis-12 conjugated linoleic acid(CLA)on maintaining ruminal homeostasis of young ruminants during the weaning transition period.Thirty neonatal lambs were selected(6 lambs per group)and euthanized for rumen microbial and epithelial analysis.The lambs were weaned at 28 d and experienced the following 5 treatments:euthanized on d 28 as the pre-weaning control(CON0),fed starter feed for 5(CON5)or 21(CON21)d,fed starter feed with 1%of CLA supplemented for 5(CLA5)or 21(CLA21)d.Results showed that the average daily weight gain and dry matter intake were significantly higher in CLA5 than CON5 group.As compared with the CON5 and CON21 group,the relative abundances of volatile fatty acid(VFA)producing bacteria including Bacteroides,Treponema,Parabacteroides and Anaerovibrio,as well as the concentrations of acetate,butyrate and total VFA were significantly increased in CLA5 and CLA21 group,respectively.Integrating microbial profiling and epithelial transcriptome results showed that 7 downregulated inflammatory signaling-related host genes IL2RA,CXCL9,CD4,CCR4,LTB,SPP1,and BCL2A1 with CLA supplementation were significantly negatively correlated with both VFA concentration and VFA producing bacteria,while 3(GPX2,SLC27A2 and ALDH3A1)and 2(GSTM3 and GSTA1)upregulated metabolism-related genes,significantly positively correlated with either VFA concentration or VFA producing bacteria,respectively.To confirm the effects of CLA on epithelial signal transduction,in vitro experiment was further conducted by treating rumen epithelial cells without or with IL-17A+TNF-αfor 12 h after pretreatment of 100μM CLA or not(6 replicates per treatment).The results demonstrated the anti-inflammatory effect of CLA via suppressing the protein expression of NF-кB p-p65/p65 with the activation of peroxisome proliferator-activated receptor gamma(PPARγ).In conclusion,CLA supplementation enhanced the ruminal microbiota-driven transcriptional regulation in healthy rumen epithelial development via rumen VFA production,and CLA may therefore serve as an alternative way to alleviate early-weaning stress and improve physiological and metabolic conditions of young ruminants.

Impact of dietary supplementation of b-hydroxybutyric acid on performance,nutrient digestibility,organ development and serum stress indicators in early-weaned goat kids

The objective of this study was to determine the effect of dietary supplementation of b-hydroxybutyric acid(BHBA)on performance,nutrient digestibility,organ development,and serum composition in earlyweaned goat kids.Sixty-four goat kids at 30 d of age were assigned to 4 treatments in a completely randomized design:1)control(basal diet);2)low(basal diet with 3 g/d per animal BHBA);3)medium(basal diet with 6 g/d per animal BHBA;and 4)high(basal diet with 9 g/d per animal BHBA).Subsequently,48(6 kids per treatment)goat kids were randomly selected and slaughtered at 60 and 90 d of age.Compared with the control group,BHBA at low and high doses increased body weight(P<0.05),average daily gain(P<0.01),and average daily starter intake(P<0.01).The BHBA improved organ development,especially at the lowest dose(P<0.01).The digestibility of dry matter and crude protein increased with age(P<0.05).However,BHBA did not affect nutrient digestibility.Compared with the control group,serum ceruloplasmin increased(P<0.05)with high BHBA level at 90 d of age.However,the serum creatinine(P<0.05)increased over time but was not affected by BHBA.The serum total antioxidant capacity and superoxide dismutase decreased with the high dose of BHBA at 90 d of age(P<0.01).In contrast,the serum glutathione peroxidase and malondialdehyde increased with the high doses of BHBA(P<0.01).Overall,low doses of BHBA were positive for growth performance,organ development,and health status against weaning stress.Whereas high doses of BHBA in the long term could negatively affect antioxidant status.

Early weaning leads to the remodeling of lipid profile in piglet jejunal crypt cells during post-weaning days

Reportedly,proteins involved in lipid metabolism change significantly in the jejunal crypt cells of earlyweaned piglets,but the exact lipid profile change remains uncertain.In the present study,32 piglets weaned at 21 d of age were randomly divided into 4 groups with 8 replicates.The jejunal crypt cells of a group of piglets on the post-weaning day(PWD)1,3,7,and 14 were isolated per time point.Crypt cell lipid profiles were analyzed using ultra-high-performance liquid chromatography coupled with hybrid quadrupole time-of-flight mass spectrometry.This study showed that piglets suffered the greatest weaning stress on PWD 3 in terms of the lowest relative weight of the small intestine,the highest relative weight of the spleen,and the highest levels of malondialdehyde,cholesterol,and low-density lipoprotein cholesterol.The lipid profile of jejunal crypt cells including carnitine,sulfatide,sphingomyelin,hexosylceramide,and ceramide greatly changed after weaning,especially between PWD3 and 14(P<0.05).The differential lipid species between these 2 d were mainly involved in the glycerophospholipid metabolism pathway.In addition,potential lipid biomarkers for weaning stress in crypt cells such as phosphatidylcholine(PC)(9:0/26:1),PC(17:0/18:2),carnitine(24:0),carnitine(22:0),sphingomyelin(d14:1/22:0),PC(P-18:0/18:4),phosphatidylethanolamine(P-16:0/20:4),phosphatidylinositol(15:1/24:4),and dihexosylceramide(d14:1/26:1)were identified.The changes in lipid profile might be related to the inflammation caused by early weaning.These findings might provide new therapeutical targets for intestinal dysfunctions caused by weaning stress.