Effects of Alcoholic and Aqueous Extract of Propolis on Growth Performance, Hemato-Immunological Parameters and Disease Resistance of Common Carp (Cyprinus carpio)

In this study, the effects of oral administration of an alcoholic and aqueous extract of propolis on growth performance indices, hematological parameters and immune responses of Cyprinus carpio were investigated. Six hundred and thirty juvenile Cyprinus carpio (weighing 58.5 +/- 4.2 g, Mean +/- SD) were randomly divided into seven equal groups in triplicates. Three groups (G1 to G3) were fed diets containing 0.1%, 0.25% and 0.5% of Propolis-ethanolic Extract (PEE) respectively, whereas groups 4 to 6 were fed a diet containing the same level of Propolis Aqueous Extract (PAE), group seven was received free extract normal food. Growth indices and hemato-immunological parameters in treated fish were evaluated and compared among the groups. The results showed a significant increase in serum lysozyme activity, total serum protein and globulin in fish fed diets containing 0.5% PEE compared to the control group (P<0.05). But no significant differences were observed in growth-performance indices and other immunological and hematological parameters compared to the control group (P>0.05). Meanwhile, cumulative mortality after the bacterial challenge of fish fed on a diet containing 0.5% PPE significantly decreased compared to control group (P<0.05). According to the results, supplementation of food with 0.5% PEE stimulated some innate immune responses and resistance against A. hydrophila infection. Then 0.5% PEE in diet can be a good candidate for immunostimulant against bacterial infection in common carp.