Feed intake, digestibility and body weight gain of sheep fed Napier grass mixed with different levels of Sesbania sesban

A randomized complete block design was employed to assess the feed intake, nutrient digestibility and live weight gains of hair type local sheep (~ 18.0 kg initial live weight) fed Napier grass (Pennisetum purpureum) mixed with different levels of Sesbania (Sesbania sesban). The treatments were sole Napier grass (control) and four Napier grass-Sesbania mixtures consisting of 100, 200, 300, and 400 g/kg of Sesbania on dry matter (DM) basis. The ratio of mixing the two feeds was adjusted every week based on DM content of each feed component to maintain a constant ratio on DM basis. The DM, ash, crude protein (CP) and acid detergent lignin (ADL) contents of the Napier grass-Sesbania mixtures increased as the proportion of Sesbania increased and the reverse was true for organic matter (OM), neutral detergent fibre (NDF) and acid detergent fibre (ADF) contents. The DM intake was higher (P < 0.05) in the mixed diets than in the sole Napier grass diet while the OM intake was higher (P < 0.05) in the diet containing 400 g/kg of Sesbania (52.9 g kg W− 0.75 day− 1) than Napier grass alone (47.5 g kg W− 0.75 day− 1). Crude protein intake increased with increased inclusion level of Sesbania in the diet. Dry matter and OM digestibilities were higher (P < 0.05) in the mixed diets containing 200, 300 and 400 g/kg Sesbania than Napier grass alone. Crude protein digestibility was significantly higher (P < 0.05) in all the mixed diets than sole Napier grass diet whereas NDF digestibility was higher in the mixed diet containing 400 g/kg Sesbania than sole Napier grass diet. The sheep that were fed the diet containing 300 g/kg Sesbania foliage showed significantly higher (P < 0.01) average daily body weight gain (103 g/day) than the unsupplemented control group (75.6 g/day). In general, all the experimental sheep showed good growth performances throughout the experimental period.