Abstract
1. The aim of the present study was to investigate whether grain type (barley or oats) and β-glucanase inclusion influence the performance and the gastrointestinal ecosystem of broiler chickens, taking the concentrations of short-chain fatty acids and lactic acid, pH, ileal viscosity, and the weight of the caeca and liver into consideration.
2. The inclusion of β-glucanase in the oat-based diet improved body weight gains. Enzyme supplementation of barley-based diets improved feed conversion efficiency and reduced intestinal viscosity.
3. Irrespective of the type of cereal, β-glucanase supplementation increased the lactic acid concentration and lowered the pH of the crop contents. No such changes in fermentation were observed in the contents of the gizzard and ileum.
4. Larger amounts of total dietary fibre and its fractions (arabinoxylans and β-glucans) in oats decreased the weight of the caeca.
5. Molar ratios of acetate, propionate and butyrate in the caecal chyme were affected by cereal type but not by enzyme supplementation. The barley-based diet increased the butyrate:propionate ratio but the opposite effect was observed with the oat-based diet.