Effect of graded levels of urea treatment on nutrient composition and in-vitro digestibility of Calliandra calothyrsus (Meissner)

Abstract

Calliandra calothyrsus (Meissner) is a multipurpose forage tree that can improve the nutrition of livestock due to its high  crude protein content. However, the shrub has low digestibility. The aim of this study was to determine the effect of graded levels of urea treatment on nutrient composition and in-vitro digestibility of C. calothyrsus leaves. Mature leaves of C. calothyrsus were  hand harvested in the first week of August 2016, after the flowering stage. They were air dried under the shed for five days in order to maintain the green colour of the leaves. They were then treated with 0% (control), 3%, 5% and 7% urea solutions for four weeks under anaerobic conditions. Some of the air dried samples were ground and analysed for nutrient composition, crude protein (CP), acid detergent fibre (ADF), neutral detergent fibre (NDF), dry matter (DM) and ash. There was an increase in CP following increase in the level of urea treatment from 210 to 320g/kg DM. A decrease was noted in fibre content with increasing level of urea treatment. Digestibility trial was conducted using the Tilley and Terry two stage method. In-vitro dry matter digestibility increased significantly at (p<0.05) with increase in urea treatment noted from 439.7-530.7g/kg DM. The results show the effectiveness of urea treatment in increasing the crude protein and in-vitro digestibility of C. calothyrsus .