PRODUCTION RESULTS, SERUM-CHOLESTEROL CONCENTRATION AND CARCASS COMPOSITION OF BROILER-CHICKENS FED DIETS BASED ON BRAN OR INNER ENDOSPERM FROM OATS WITH AND WITHOUT ENZYME SUPPLEMENTATION

Broiler chickens were fed diets based on brain or inner endosperm from oats (Avena sativa L), given with or without a supplementary fibre-degrading enzyme, in order to study the effects of the dietary fibre on production results, carcass composition and serum cholesterol concentration. Enzyme supplementation of the oat-bran-based diet significantly improved production results and caused an increase in total serum cholesterol concentration and carcass fat whereas carcass crude protein and water content decreased. On enzyme supplementation of the diet based on inner endosperm, a significant although less pronounced improvement in production results was obtained. Chickens fed the inner endosperm diet generally had higher total serum cholesterol concentrations which increased further on enzyme supplementation. Carcass fat content also increased on enzyme supplementation, and at day 27 chickens fed the enzyme-supplemented diet based on inner endosperm had the highest carcass fat content in comparison with all other diets. The results show that dietary fibre exerts a greater influence on total serum cholesterol concentration than energy or fat intake since chickens fed the enzyme-supplemented oat-bran diet had the highest intake of metabolisable energy and fat but still displayed lower total serum cholesterol concentrations than chickens fed the enzyme-supplemented low fibre diet based on inner endosperm.