Abstract: The aim of this study was to investigate the effect of silage sugarcane leaf replacing different ratio of King grass on growth performance,nutrient apparent digestibility and serum biochemical indices of Hainan Black goats.A total of 20 3-month-old Hainan Black goats with an average weight of (6.96±0.49) kg were selected (half male and hale female) and randomly divided into 5 groups with 4 replicates per group and 1 goat per replicate.The goats in the control group were fed the basal diet including concentrate and roughage,roughage was King grass.The goats in the groups 1 to 4 were fed with the equal concentrate,roughage (fresh King grass) was replaced with 25%,50%,75% and 100% silage sugarcane leaf,respectively.The pre-test period lasted for 5 days and the trial period lasted for 30 days.The results showed that compared with control group,the average feed intake of crude feed and average feed intake of total dry matter in group 3 were significantly increased (P< 0.05),there were no significant differences in the average daily gains,average feed intake of concentrate and F/G among all groups (P> 0.05).Compared with control group,the apparent digestibility of Ash and P in group 3 were significantly increased (P< 0.05),the apparent digestibility of Ash,NDF,ADF and Ca in group 4 were significantly increased (P< 0.05).No significant difference was showed between groups 3 and 4 (P> 0.05).There were no significant differences in serum biochemical indices among all groups (P> 0.05).In conclusion,silage sugarcane leaf replaced certain percentage of King grass in roughage could improve the growth performance and nutrient apparent digestibility to some extent,and had no bad effect on the serum biochemical indices of goats,the optimal proportion of silage sugarcane leaf in roughage was 75%.

Key words: Hainan Black goats; silage sugarcane leaf; growth performance; nutrient apparent digestibility; serum biochemical indices