Feed endoxylanase type and dose affect arabinoxylan hydrolysis and fermentation in ageing broilers

Area of Science:

• Animal Nutrition
• Enzyme Technology
• Gut Microbiology

Background:

• Endoxylanases are widely used in poultry feed to enhance broiler performance.
• Variable responses to different endoxylanase products hinder a clear understanding of their in vivo functionality.
• Investigating specific endoxylanase types and doses is crucial for optimizing their application.

Purpose of the Study:

• To investigate the impact of endoxylanase type (Bacillus subtilis vs. Nonomuraea flexuosa) and dose on arabinoxylan (AX) hydrolysis and fermentation in broilers.
• To understand how broiler age influences the effects of endoxylanase supplementation on AX digestion.
• To correlate AX hydrolysis and fermentation patterns with broiler performance outcomes.

Main Methods:

• A wheat-soy based diet was supplemented with two types of endoxylanase at three different doses (10, 100, 1,000 mg/kg) or a control diet.
• A total of 1,057 broiler chicks (Ross 308) were used in digestibility and performance trials.
• AX content, structure, digestibility, and short-chain fatty acids were analyzed at the ileum, caeca, and excreta at days 11 and 36.

Main Results:

• Endoxylanase supplementation led to increased AX solubilization and reduced intestinal viscosity compared to the control.
• High doses of endoxylanase were required for significant AX hydrolysis throughout the gastrointestinal tract.
• Bacillus subtilis endoxylanase increased ileal viscosity by creating soluble AX, while Nonomuraea flexuosa endoxylanase promoted caecal AX fermentation in young broilers.

Conclusions:

• The type and dose of endoxylanase determine the characteristics of AX substrates formed in the broiler gut.
• These AX substrates influence intestinal viscosity and microbial fermentation, impacting AX digestion and performance.
• Understanding these interactions is key to optimizing endoxylanase use in wheat-soy based broiler diets, especially in young birds.