Abstract
This study investigated the effects of the dietary supplementation of Zizyphus mauritiana leaf meal (ZLM) on the performance of Yankasa lambs. Twenty five lambs aged between 6 and 8 months were randomly divided into five groups of five animals each in a completely randomized design to receive supplementary diets containing 0, 10, 20, 30 and 40% ZLM as replacement for cotton seed cake in concentrate supplement to a maize stover basal diet for a period of 120 days. Inclusion of ZLM in the supplement did not significantly (P>0.05) affect nutrient intake. There was a significant (P<0.05) depression on dry matter (DM), organic matter (OM), neutral detergent fiber (NDF) and acid detergent fiber (ADF) digestibility, with 30 and or 40% increases in the level of ZLM inclusion in the supplementary diet. Feeding ZLM containing diets particularly at 30 and 40% levels significantly (P<0.05) influenced nitrogen utilization. Fecal nitrogen excretion significantly (P<0.05) increased with ZLM supplementation. Control (0%) and 10% level of inclusion had similar and significantly (P<0.05) lower fecal N loss (14.30 and 14.94 g/d), followed by 20% (15.42 g/d), with T4 and T5 having significantly (P<0.05) higher fecal N loss (22.04 and 22.89 g/d). Urinary N loss was significantly higher (P<0.05) in lambs offered 0, 10 and 20% ZLM (10.88, 11.98 and 11.02, respectively) diets compared to 30% (10.06) and 40% (9.89) receiving higher levels of ZLM, which were significantly (P<0.05) lower. Nitrogen retention was highest in control (26.19), followed by 10 and 20% ZLM (24.42 and 24.14), which were similar and higher than 30 and 40% supplementations (17.15 and 15.97, respectively). Nitrogen retention as % of intake was highest (50.98%) in animals fed 0% and was least in 40% ZLM supplementation (32.75%). It was concluded that inclusion of ZLM in concentrate diet at 10-20% inclusion levels gave best result in terms of performance than when the leaf meal is included at higher levels to ram lambs.