The effects of different levels of dietary zeotene on growth, carcass biochemical composition and immune system function of common carp (Cyprinus carpio) fingerling

In this study, the effect of zeotene, was studied on some growth parameters, carcass composition and immunity of common carp fingerlings. 180 fish (mean weight 20.3±0.1g) were randomly divided into 4 treatments and fed for 8 weeks, with diets containing 0 (control), 2, 4 and 8g/Kg zeotene. At the end of the experiment, the average of final weight, condition factor, feed efficiency ratio, protein efficiency ratio, hepatosomatic index and viscerosomatic index increased and FCR decreased in treatments 2 and 4 grams of zeotene (P<0.05). The highest carcass moisture content and the lowest carcass fat were related to treatments 2 and 4 grams of zeotene (P<0.05). Carcass ash in treatment 8 grams of zeotene was the highest (P<0.05). Among serum biochemical parameters, the amounts of globulin, lysozyme, complement and IgM in treatment 4 grams of zeotene was significantly higher than control and treatment 8 grams of zeotene (P<0.05). The lowest and the highest numbers of WBCs were seen in 8 and 2 grams of zeotene, respectively. The highest and the lowest percentage of lymphocytes and neutrophils were seen in 2 and 4 grams of zeotene, respectively. In conclusion, 4 grams of zeotene per kilogram diet can improve growth factors, carcass quality and immune parameters of common carp.