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

Abstract

Background: This study aimed to investigate the hydration properties of different-source fibrous materials by comparing 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% microcrystalline cellulose (MCC), 5% wheat bran (WB), 5% Moringa oleifera leaf powder (MOLP), or 5% sugar beet pulp (SBP), followed 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 property 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 relative 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 production. 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.

Keywords: Diarrhea; Dietary fiber; Hydration property; Intestinal health; Nutrient digestibility; Weaned piglet.

Fig. 1

Effects of dietary fibers with different WBC on the intestinal barrier and inflammatory cytokines of weaned piglets. (A, B) Plasma diamine oxidase and D-lactate, intestinal permeability-related plasm biomarkers. (C-H) The mRNA expression of intestinal barrier and cytokine related genes in jejunum, ileum, and colon of weaned piglets. CON, control diet group; MCC, 5% microcrystalline cellulose diet group; WB, 5% wheat bran diet group; MOLP, 5% Moringa oleifera leaf powder diet group; SBP, 5% sugar beet pulp diet group; ZO-1, zonula occludens-1; ZO-2, zonula occludens-2; CLDN-4, claudin-4; OCLN, occludin; TNF-α, tumor necrosis factor-α; IL-1β, interleukin 1β; CSF3, colony stimulating factor 3; IL-10, interleukin 10. ^a−cBars with different lowercase letters differ significantly (P < 0.05), and P-diet represents the P values between the five groups. P-HP stands for P value between low hydration property groups and medium hydration property groups. Values are presented as means ± Pooled SEM

Fig. 2

Gas production curves of in vitro fermentation of fibrous ingredients. DM, dry matter; MCC, microcrystalline cellulose; WB, wheat bran; MOLP, Moringa oleifera leaf powder; SBP, sugar beet pulp. Values are presented as the mean values of two replicates