Influence of graded inclusion of white lupin (Lupinus albus) meal on performance, nutrient digestibility and intestinal morphology of broiler chickens.

The aim of this study was to investigate the effect of white lupin (Lupinus albus) meal (WLM) addition on the intestinal viscosity, bird performance, nutrient utilisation and villi morphology of growing broiler chicks. The experiment was conducted with 480 broiler chicks divided into 6 dietary treatments, including a maize-soybean meal control diet (CON) and 5 experimental diets containing 100, 150, 200, 250 and 300 g/kg WLM. During the period from d 0 to 35, birds fed on 200 or higher WLM/kg were characterised by lower body weight gain and feed intake than CON. The use of 150 g of WLM/kg increased feed conversion ratio (FCR) compared to CON treatment. Apparent metabolisable energy corrected to zero N balance (AMEN) and apparent ileal digestibility of dry matter, ether extract, crude protein and starch, linearly decreased as WLM increased from 0 to 300 g/kg. There was a quadratic effect of WLM dose on sialic acid excretion. A strong negative linear correlation was found between the excretion of sialic acid and AMEN. The viscosity of ileal digesta was linearly increased as WLM increased. The effect of WLM dose on ileum villus height (VH) was linear, while that on ileum villus area (VA) was quadratic. Both parameters decreased as WLM increased from 0 to 300 g/kg. In conclusion, the use of over 150 g/kg of WLM in broiler diets depressed performance results. However, depression of nutrient utilisation was only observed when 250 or 300 g/kg of WLM was used.