The Effect Of Dietary Pectic Oligosaccharide Supplementation On The Growth Performance, Immune Function And Gut Health In Weaned Piglets Challenged By Rotavirus

This experiment was conducted to investigate the effect of dietary pectic oligosaccharide (POS) supplementation on the growth performance, immune function and intestinal health in the weaned pigs challenged by rotavirus (RV). A total of 28 healthy crossbred (Duroc×Landrace×Yorkshire) piglets (7.54±0.31 kg) weaned at 21 d were randomly assigned to one of four groups (n=7/group) in a 2×2 factorial design experiment. Piglets were fed with the two diets supplementing POS levels of 0 and 200 mg/kg (namely two groups per dietary treatment) for 18 d. On d 15, all piglets were orally infused with RV or sterilized MEM medium. The results were listed as follows.(1) RV challenge reduced average daily feed intake (ADFI) and average daily gain (ADG) (P?0.05), and enhanced the diarrhea rate, average diarrhea index, feed/gain (F/G) and serum UN level in the piglets (P?0.05). RV challenge also increased the serum RV-Ab content and the NSP4 percentage of the jejunum and ileum in the piglets (P?0.05). Dietary POS supplementation enhanced ADFI and ADG (P?0.05), reduced the F/G, diarrhea rate, average diarrhea index and serum UN level (P?0.05), and attenuated the effect of RV challenge on the serum UN level in the piglets (P?0.05).(2) RV challenge decreased the amylase, lipase and tryptase activities in the jejunal digesta of piglets (P?0.05). However, dietary POS supplementation could stimulate these three digestive enzyme activities in the jejunal digesta of piglets (P?0.05). In PRV-challenge pigs, supplementing POS in diets attenuated the effect of PRV infusion on the lipase and tryptase of the jejunal digesta in the piglets (P?0.05).(3) RV challenge increased the serum IgA (P?0.05) and IgG (P=0.08) concentrations, and enhanced IL-2 level of jejunum (P=0.07) and ileum(P=0.08) in the piglets. Dietary POS supplementation could also enhance the serum concentrations of IgA (P=0.06) and IgG (P?0.05), increase sIgA?IFN-? and IL-4 levels of jejunum and ileum (P?0.05), and attenuate the effect of RV challenge on the jejunal sIgA and IFN-? levels (P?0.05) in the piglets. Furthermore, dietary POS supplementation could further enhance the serum IgG concentration of the piglets challenged by PRV(P?0.05).(4) RV challenge reduced the villus height and villus height/crypt depth (v/c) of the jejunum and ileum in the piglets (P?0.05). Dietary POS supplementation enhanced the villus height and v/c of the jejunum and ileum in the piglets (P?0.05). In PRV-challenge pigs, supplementing POS in diets attenuated the effect of PRV infusion on the villus height and v/c of the jejunum in the piglets (P?0.05).(5) RV challenge downregulated the gene expressions of ZO-1, occludin, Bax, Bcl-2, MUC1 and MUC2 in the jejunal or ileal mucosa of piglets (P?0.05). Dietary POS supplementation upregulated the gene expressions of ZO-1, occludin, Bcl-2, MUC1 and MUC2 in the jejunal or ileal mucosa of piglets (P<0.05). Additionally, dietary POS supplementation could also attenuate the effect of RV challenge on the gene expressions of ZO-1, occludin, Bcl-2 and MUC2 in the jejunal or ileal mucosa of piglets (P?0.05).(6) RV challenge increased the pH of the jejunal, ileal and cecal digesta, enhanced the Escherichia coli count of the ileal and cecal digesta (P?0.05), and decreased the Lactobacillus, Bifidobacterium and total bacteria counts of the ileal or cecal digesta in the piglets (P?0.05). Dietary POS supplementation increased the Lactobacillus, Bifidobacterium and total bacteria counts of ileal and cecal digesta (P?0.05), decreased the pH of the the jejunal, ileal and cecal digesta, and reduced the Escherichia coli count of the ileal and cecal digesta in piglets (P?0.05). Furthermore, dietary POS supplementation could attenuate the effects of RV challenge on pH and the Lactobacillus, Bifidobacterium and total bacteria counts of the ileal or cecal digesta in the piglets (P?0.05).(7) RV challenge decreased the content of acetic acid and total volatile fatty acids (VFA) in cecum of piglets (P?0.05). Dietary POS supplementation increased the content of acetic acid and total VFA in cecum of piglets (P?0.05). In PRV-challenge pigs, supplementing POS in diets attenuated the effect of PRV infusion on the content of acetic acid and total VFA in cecum of piglets (P?0.05)(8) RV challenge increased the malondialdehyde (MDA) concentration of the jejunum, ileum and serum (P?0.05), and decreased the total antioxidant capacity (T-AOC) of the jejunum, ileum and serum in the piglets (P?0.05). Dietary POS supplementation decreased the MDA concentration of the jejunum, ileum and serum (P?0.05), and increased the T-AOC of the jejunum, ileum and serum in the piglets (P?0.05). Dietary POS supplementation could attenuate the effects of RV challenge on the MDA concentration and the T-AOC of the jejunum, ileum or serum in piglets (P?0.05).In conclusion, these results suggest that RV challenge could induce a serious diarrhea, decreasing antioxidant capacity, intestine damage, immune dysfunction and lower nutrients utilization, which led to the decline of growth performance. However, dietary POS supplementation improved the growth performance, and alleviated the diarrhea induced by RV challenge in piglets, which could be due that dietary POS supplementation might improve the utilization of nutrients, immunity, antioxidant capacity and intestinal barrier function in the piglets.