Effect of Dietary Chlorella on the Growth Performance and Physiological Parameters of Gibel carp, Carassius auratus gibelio

In the present study, a chlorella-free control diet (C) and five experimental diets supplemented with 0.4~2.0% Chlorella were formulated. The gibel carp (Carassius auratus gibelio), one of the commercial fish in China, were fed with the designed diets for 60 days. At the end of trials, parameters of growth performance, blood and the digestive enzyme were analyzed. The results showed that the optimal dietary level of Chlorella as an additive in gibel carp diet was 0.8~1.2%. The growth performance including RGR, SGR, PER and PDR in 0.8 and 1.2% chlorella-adding group were significantly higher than that of control group (P<0.05). Meanwhile, some blood parameters including total protein, lysozyme in these two groups were also higher than in the control group. Furthermore, the chlorella could increase the digestive enzyme, e.g. amylase, lipase and protease in hepatopancreas and intestine. Our study confirmed that the Chlorella could be used as additive in gibel carp farming and the optimal adding level of Chlorella was 0.8%-1.2%, which could promote the growth performance, immune response and the activity of digestive enzyme.