Effects of alfalfa on growing performance and digestive enzymes of Bluntnose Black Bream

1530 Bluntnose Black Bream （Megalobrama amblycepnala）（59.900.84 g）were randomly divided into six treatments with three replicates to study the effects of alfalfa meal and fresh alfalfa on its production performance and the digestive enzymes. The control group was fed with the basal diets（0 alfalfa meal）, the other groups were fed with diets containing 8%(group I ), 16%( group II), 24% （group III）and 32%（group IV） alfalfa meal and fresh alfalfa（group V）respectively. The results showed that 1）Comparing with the control group, the average daily gain and relative growth rate of the fishes fed with 8% or 16% alfalfa meal had very significantly increase (P 0.01), group III was higher and group IV was lower than that of control, but no significant difference was observed (P0.05). 2) The activity of digestive enzymes of all experimental groups was higher than the control group. The protease in hindgut of groupⅡ and the amylase in hepatopancreas of group IV were significantly higher than control group (P0.05). 3) Compared with the control, the economic benefits of the group I and Ⅱ were improved. 4) Feeding with fresh alfalfa could increase digestive enzymes activities, improve growing performance and achieve better economic profits.