Increasing viscosity of the intestinal contents alters small intestinal structure and intestinal growth, and stimulates proliferation of enterotoxigenicEscherichia coliin newly-weaned pigs

Abstract

Sources of viscous soluble fibre, such as barley and oats, have often been included in the weaning diet of the pig to accelerate development of the large intestine. Inclusion of a non-fermentable, viscous compound, sodium carboxymethylcellulose (CMC), in a low-fibre weaning diet was tested to assess the influence of digesta viscosity on the gut in the absence of increased fermentation. Two CMC sources, of low and high viscosity, were added to cooked rice-based diet at 40 g/kg total diet. A third control rice diet did not contain any CMC. Diets were fed for 13 d following weaning at 3 weeks of age. Addition of CMC to the diet significantly increased the intestinal viscosity of digesta within the small (P,0 : 001) and large (P,0 : 05) intestine. No simple association was found between increases in intestinal viscosity and effects on intestinal morphology and whole-body growth. The average empty-body-weight gain and the small intestinal villus height increased with low-viscosity CMC, but decreased with the high-viscosity CMC group. The full large intestinal weight increased in all pigs fed CMC. Dietary CMC (both low-and high-viscosity) increased the percentage moisture of digesta and faeces, and was associated with increased faecal shedding of enterotoxigenic haemolytic Escherichia coli. Feed ingredients in weaning diets that excessively increase the viscosity of the intestinal digesta may be detrimental to pig health and production.

Purified cellulose, soybean hulls and citrus pulp as a source of fiber for weaned piglets

“…Thus, the more soluble this feed fraction, the greater the viscosity (McDonald et al, 2001) and the lower the pH of the digesta , due to the fermentative potential of the fiber. The soluble fiber content of citrus pulp is high (31 %), which can justify the increase in viscosity of the digesta in the stomach and cecum at both 35 and 50 days of age, respectively.…”

Deregulation of intestinal anti-microbial defense by the dietary additive, maltodextrin

“…Notable studies have demonstrated a direct effect of these compounds on mucosal barrier integrity, which translates to exacerbated intestinal inflammation or increased bacterial burdens in animal models. 17,18,27 Likewise, restrictive diets that eliminate processed foods are showing clinical Figure 3. Consumption of MDX decreases the mucosal barrier of the intestine and increases the proximity of commensal bacteria to the epithelial layer.…”

“…1). 16 Additionally, MDX consumption by preterm piglets lead to the expansion of ileal E. coli populations 17 and induced necrotizing enterocolitis in these animals, but not in fully developed pigs. 18 Increased levels of E. coli and AIEC strains have been repeatedly observed in ileal CD patients, suggesting a role for E. coli in disease pathogenesis.…”

A wheat-based diet enhances colonization with the intestinal spirochaeteBrachyspira intermediain experimentally infected laying hens

“…The samples were diluted 1:1 (v/v) with distilled water, mixed and centrifuged at 12 000g for 8 min. The viscosity of 0.5 ml supernatant fractions was measured at 258C, applying a shear rate of 60/sec (McDonald et al ., 2001). …”