orabase and Diarrhea

The present study was designed to evaluate the effect of increased viscosity of the intestinal digesta on proliferation of enterotoxigenic Escherichia coli and the intestinal spirochaete Brachyspira pilosicoli in weaned pigs. Pigs were fed an experimental diet based on cooked white rice (R), which was supplemented with carboxymethylcellulose (CMC; 40 g/kg diet) to increase digesta viscosity. Thirty-six piglets weaned at 21 d of age were divided into six groups, three of which were fed R and three Addition of CMC increased digesta viscosity in the ileum (P=0.01), caecum (P=0.0007) and colon (P=0.0035), without increasing indices of large intestinal fermentation. Pigs fed developed a natural infection with enterotoxigenic E. coli after weaning and had more (P<0.0001) diarrhoea than pigs fed R. Subsequent experimental infection of two groups of pigs with B. pilosicoli resulted in more (P<0.0001) colonisation in pigs fed than R. At this time, all pigs fed had wetter (P<0.0001) faeces than those fed R, irrespective of whether they were infected with B. pilosicoli, but infected pigs also had an increased (P=0.025) number of days with diarrhoea post-infection irrespective of diet. In pigs fed it was not clear to what extent the increased viscosity associated with CMC, or the concurrent infection with enterotoxigenic E. coli, was responsible for the increased proliferation of B. pilosicoli. In a second experiment, five pigs that were weaned onto an R diet were transferred onto 3 weeks later. These pigs did not develop a natural infection with enterotoxigenic E. coli after the diet change, confirming the particular susceptibility of pigs to enterotoxigenic E. coli proliferation immediately post-weaning.

Topics: Analysis of Variance; Animals; Carboxymethylcellulose Sodium; Diarrhea; Disease Susceptibility; Escherichia coli Infections; Female; Gastrointestinal Contents; Oryza; Spirochaetales Infections; Sus scrofa; Swine; Swine Diseases; Time Factors; Viscosity; Weaning

Viscosity-enhancing agents such as carboxymethylcellulose (CMC) can alter absorption of solutes and fluid exchange in the small intestine. We investigated whether the standard World Health Organization oral rehydration solution (WHO-ORS) with the addition of CMC would improve net water and sodium absorption in rats using an in vivo intestinal perfusion technique. Four WHO-ORS, containing either 0, 2.5, 5.0, or 10.0 g/L of CMC, were perfused in rats with a well-tested model of cathartic-induced chronic osmotic diarrhea (D) and in normal controls (C). In D rats, the ORSs with CMC improved sodium absorption at the three concentrations used (p < 0.01). The same effect was shown in C rats. Net water absorption was also enhanced in D rats given ORSs with CMC, although the changes in C animals were less marked. The improvement in sodium and water absorption in both C and D rats positively correlated with the log of relative ORS viscosity. Ultrastructural examination of tissues perfused with 10 g/L of CMC showed an extended brush border glycocalyx. This study indicates that CMC added to WHO-ORS in the perfused rat jejunum improves the effectiveness of the solution by increasing sodium and water absorption.

Topics: Animals; Carboxymethylcellulose Sodium; Chronic Disease; Diarrhea; Disease Models, Animal; Fluid Therapy; Intestinal Absorption; Male; Microscopy, Electron; Rats; Rats, Sprague-Dawley; Rehydration Solutions; Sodium; Viscosity; Water

1. A comparison was made of the effect of a fibre-free diet and diets containing non-digestible polysaccharides on rat caecal and colonic physiology and microflora. 2. All polysaccharide-containing diets led to enlargement of the caecum and colon, associated with increased weight of contents, and of tissue. Carboxymethylcellulose (CMC) had the most marked effect and animals given this also had watery faeces. 3. The density of bacteria in the caecum and colon varied significantly with diet and the proportion of aerobic bacteria in the flora was increased by the CMC diet. 4. In vitro, CMC and hydroxypropylmethylcellulose were poorly fermented. 5. There was a high correlation (caecum r 0.93; colon r 0.94) between tissue weight and wet weight of organ contents but no correlation with bacterial density, number of bacteria per organ, moisture content or short-chain fatty acid content. 6. It is concluded that caecal and colonic enlargement is due to tissue hypertrophy in response to increased bulk of contents, irrespective of the nature of that bulk which varies with diet; it is unlikely that short-chain fatty acids or other microbial metabolites are the stimulus for the trophic response seen when non-digestible dietary polysaccharides are fed to rats.

Topics: Adaptation, Physiological; Animals; Carboxymethylcellulose Sodium; Cecum; Colon; Diarrhea; Dietary Carbohydrates; Escherichia coli; Feces; Fermentation; Hypertrophy; Male; Organ Size; Polysaccharides; Rats; Rats, Inbred Strains; Streptococcus

Segments of rat ileum and colon were infused in vivo to test if 0.1 M lactate, 10(-4) M H+, or both altered mucosal structure and function. In the first series of experiments, lactate concentration was kept at 0.1 M while H+ was varied from 10(-4) to 10(-7) M. Lactate and 10(-4) M H+ in the colon, and lactate and 10(-5) M H+ in the ileum depressed net water transport and caused sloughing of superficial absorptive cells. In the second series of experiments, H+ concentration was kept at 10(-4) by using carboxymethylcellulose, rather than organic acids, to buffer the infusion mixture; the concentration of lactate was varied from 0 to 0.1 M. Mucosa remained normal after infusions of 10(-4) M H+ alone. Addition to the 10(-4) M H+ infusion of 0.1 M lactate in the colon or 0.075 M lactate in the ileum caused increased mucosal sloughing. Thus lactate plus H+ (or unionized lactic acid) alters colonic and ileal mucosa. Because such high concentrations of lactate and H+ are found in subjects malabsorbing carbohydrates, the present experiments support the contention that H+ and organic acids are etiological factors in some cases of chronic fermentative diarrhea.

Topics: Animals; Carboxymethylcellulose Sodium; Colon; Diarrhea; Hydrogen; Ileum; Intestinal Mucosa; Ions; Lactates; Male; Rats; Rats, Inbred Strains; Water