IMMUNOSTIMULANT AND DIGESTIVE ENZYME ACTIVITY OF VERATRUM Veratrum album IN RAINBOW TROUT Oncorhynchus mykiss

In this study, the immunostimulant effects of veratrum (Veratrum album) and its growth promoting effects were investigated in rainbow trout (Oncorhynchus mykiss). For this purposes, veratrum aqueous methanolic extract was added to the basal diet at the rate of 0 (Control), 250, 500 and 1000 mg kg^-1. The fish were fed with this diet during 60 days and every 20^th day of the study some humoral immune parameters, growth performance and digestive enzyme activity were determined. Superoxide radical releasing was showed no differences in group 250 mg kg^-1 (P>0.05) but other group's was significantly decreased on 20 th day of the study (P<0.05). At the end of the study, superoxide radical releasing was determined higher than control and 500 mg kg^-1 group in 250 and 1000 mg kg^-1 groups (P<0.05). Myeloperoxidase activity was significantly increased in all experimental groups especially in 40^th and 60^th day of the study compared to control (P<0.05). Lysozyme activity was significantly increased in all experimental groups and the highest value was determined in the 250 mg kg^-1 group. In the other sampling time lysozyme activity was increased in 250 and 500 mg kg^-1 groups (P<0.05). Amylase was significantly decreased in all experimental groups compared to control (P<0.05). Pepsin was decreased in 250 mg kg^-1 group and no differences was observed in 500 and 1000 mg kg^-1 group. Lipase was showed no differences. Trypsin was significantly decreased in 500 and 1000 mg kg^-1 and no differences was determined in 250 mg kg^-1 group. In all experimental group SGR was negatively affected and decreased compared to control. All these result showed an increased humoral immune results. Growth was significantly decreased in experimental groups.