Application of glycoside hydrolase family 43 (GH43) in broiler feed: a potential approach to improve digestibility, gut microbiota, and broiler chicken performance

Cereal grains, such as wheat and corn, are commonly used as a primary source of energy in broiler diets. However, these grains are rich in non-starch polysaccharides (NSPs), particularly arabinoxylan (AX). High levels of soluble AXs generate digesta viscosity. The increased viscosity leads to decreased transit rate, limited contact between digestive enzymes and substrates, and increased bacterial fermentation in the small intestine, thus resulting in poor growth performance of broilers. It was found that supplementation of xylanases and debranching enzymes of glycoside hydrolases family 43 (GH43) in the wheat-based diet showed a significant reduction in viscosity. In vivo studies indicated the enhanced release of arabinose and xylose residues in ilium and jejunum, suggesting the degradation of AX and, in turn, reduction of digesta viscosity. In addition, xylan oligomers derived from AX degradation stimulated the abundant growth and proliferation of the bacteria in the clusters of Lactobacillaceae, Enterococcaceae, Clostridiaceae, Lachnospiraceae, and Ruminococcaceae in the gut microbiome, suggesting the prebiotic effects. Quantification of short-chain fatty acids in the ceca of the broiler gut fed with GH43 xylanases showed the increased concentration of butyrate, which might be responsible for immune system stimulation and might explain better feed intake. Overall, supplementation of GH43 and other related enzymes in broiler diets is an attractive means to improve growth performance and gut health of broilers.

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