Effect of dietary supplementation of xylanase alone or combination of xylanase and β-glucanase on growth performance, meat quality, intestinal measurements, and nutrient utilization in broiler chickens.

OBJECTIVE

The current study aimed to investigate the effect of dietary supplementation of xylanase alone or combination of xylanase and β-glucanase in high non-starch polysaccharides (NSP) diets with low energy on growth performance, meat quality, intestinal measurements, stress responses, and energy and nutrient utilization in broiler chickens.

METHODS

A total of four hundred 8-d-old Ross 308 broiler chickens were randomly allotted to 1 of 4 treatment groups with 10 replicates. A positive control (PC) diet was formulated with adequate energy and nutrients, whereas a negative control (NC) diet had 100 kcal/kg less nitrogen-corrected apparent metabolizable energy than the PC diet with increasing inclusion of high NSP ingredients. Two additional diets were produced by supplementing 0.1% xylanase alone or 0.1% xylanase and β-glucanase mixture in the NC diet. Experiments lasted for 27 d.

RESULTS

Birds fed PC diets had less (p<0.05) feed conversion ratio (FCR) than those fed NC diets. Birds fed NC diets supplemented with xylanase alone or combination of xylanase and β-glucanase had less (p<0.05) FCR than those fed NC diets. Dietary supplementation of xylanase alone in NC diets exhibited the highest (p<0.05) breast meat pH among dietary treatments. Birds fed PC diets or NC diets supplemented with xylanase and β-glucanase combination exhibited greater (p<0.05) villus height:crypt depth ratio than those fed NC diets. Dietary supplementation of xylanase alone and combination of xylanase and β-glucanase in NC diets decreased (p<0.05) ileal digesta viscosity and increased (p<0.05) xylo-oligosaccharide concentrations in the gastrointestinal tract (GIT) compared with NC diets without affecting energy and nutrient utilization in NC diets.

CONCLUSION

Dietary supplementation of xylanase in high NSP diets with low energy concentrations improves growth performance by decreasing digesta viscosity and increasing concentrations of xylo-oligosaccharides in the GIT of broiler chickens. However, little additional benefits of β-glucanase supplementation in combination with xylanase are identified for broiler chickens.