Growth performance of, and mimosine excretion by, young chicks fed on leucaena leucocephala

Abstract

Growth performance and mimosine output in excreta have been measured in young chicks fed on diets containing three forms of Leucaena leaf meal (LLM) imported from Malawi. In one of the experiments, the effects of supplementation of LLM with selected metal ions and enzymes were also measured. Growth and efficiency of food utilisation were similar in groups fed on a control soya bean meal diet or a basal diet containing 150 g kg −1 of the whole leaf (WL) form of LLM. Supplementation of this basal LLM diet with FeSO 4 or Al 2(SO 4) 3 had little effect on growth or efficiency of food utilisation, but the ratio of mimosine output to mimosine ingested (MO/MI) increased from 0.781 to 0.881 and 1.003 on addition of FeSO 4 and Al 2(SO 4) 3, respectively. Growth performance was unaffected by the addition of an enzyme mixture (containing cellulase, acid and neutral proteases and alpha amylase) to the basal LLM diet. In the second experiment, two other forms of LLM were also tested: a ground leaf (GL) form, and a powder produced by grinding pellets of Leucaena leaf (GP). The WL and GP forms were each added at 50 and 100 g kg −1 diet, and the GL form at 100 g kg −1 diet. These diets permitted daily intakes of mimosine ranging from 80 to 350 mg per replicate of 4 chicks. In comparison with control groups, growth performance was not impaired significantly in any of the LLM-fed groups. Mimosine excretion was high in all LLM-fed groups, the GP form inducing a maximum MO/MI ratio of 0.924.