Influence of Exogenous Xylanase on Performance and Nutrient Digestability of Broilers Fed Wheat-Based Diets

Hi Rafa. Hope all is well with you. Neonates generally have compromised nutrient recovery compared with older animals and so yes, there is more room for improvement in nutrient digestibility in the young animal. However, xylanases, I believe, impart most of their effect through establishing and maintaining a distal GI tract microflora that competes effectively with pathogens and stimulates desirable physiological effects. One of these effects is the ileal brake mechanism which may be stimulated by fermentation of xylo-oligomers created by xylanase. This increases gastric residency, improving digestibility of a range of nutrients (especially protein). Importantly this mechanism establishes over time and so we need to feed xylanase from day old and should not expect immediate response. A balance then between augmentation of the immature neonatal digestive architecture and the establishment and maintenance of a beneficial microflora in the older animal.