Cereal Non-Starch Polysaccharides in Pig Diets Influence on Digestion Site, Gut Environment and Microbial Populations

Högberg, A. 2003. Cereal non-starch polysaccharides in pig diets. Influence on digestion site, gut environment and microbial populations. Doctoral thesis. ISSN 1401-6249, ISBN 91-576-6437-4 This thesis is based on three different studies comprising the weaning and the growing period, aiming at monitoring the influence of cereal non-starch polysaccharides (NSP) and dietary enzyme supplementation on gastro-intestinal processes in pigs. The diets were based on cereals and cereal by-products, and composed to contain different amounts of total as well as soluble NSP. Results from these studies have shown that with increased NSP content, the reduction in digestibility of organic matter (OM) was twice as high in the small intestine than in the total tract, both in newly weaned piglets and growing pigs. An increased proportion of insoluble NSP decreased the digestibility of OM and fibre components in the small intestine of the newly weaned piglets and in the total tract of growing pigs. The gut environment, as described by content and proportions of organic acids (OA) and pH, as well as total microbial populations and coliform diversity, was altered by NSP content and solubility, whereas enzyme supplementation influenced the distribution of OA in the small intestine. PVTC-cannulation did not influence the coliform flora, and results obtained from PVTC-cannulated pigs were concluded to reflect true intestinal conditions. In conclusion, these results indicate that the dietary content of total and soluble NSP influence gastro-intestinal processes such as digestion site, gut environment and microbial populations in different ways in newly weaned piglets and in growing pigs. Therefore, NSP constitute an important tool with possibilities to influence gut health in pigs, and may therefore offer prospects to optimise the feed for pigs of different