Samad Bahrami Babaheydari
Prevalence of disease in cultural systems is the most important problem in aquaculture. Usually, antibiotics are used to control fish disease as well as stimulate and promote growth and efficiency of diets. Because of some disadvantages of antibiotic usage, such as development of antibiotic-resistant microorganisms and efficacy reduction of antibiotics, using natural immunostimulants is to be considered. It is well know that not only the innate immune system in fish can be triggered by these materials, but also they have beneficial effects on growth, FCR and quality of body composition.Wood betony (Stachyslavandulaefolia Vahl) have several beneficial effects. to evaluate the effects of wood betony on growth parameters(including final body weight, SGR, CF, WG and FCR), chemical body composition (including protein, moisture and lipid),hematological parameters(including Hb, Hct, RBC, WBC, MCH, MCV, MCHC, lymphocyte, monocyte and neutrophil count),biochemical parameters (including TP, Alb, Glb, Chol and Tg), immune activity (lysozyme activity)and stress response of common carp (Cyprinuscarpio)juveniles, 144 fish were divided equally among four groups, each comprising three replicates. Groups 1 was the control (fed on base diet), groups 2, 3 and 4 were fed onwood betony supplemented diet containing 4, 8 and 16 ml/kgdietfor 70 days, respectively.The results showed no significantly difference betweenhaemathological parameters exept RBC (P>0.05). Therefore, body compositions were not affected by different levels of plant extract.Thefinal weight, food conservation, condition factor and weight gain were significantly improved by wood betony (P<0.05).There were no significant differences in hemoglobin, hematocrit, mean erythrocyte hemoglobin, mean erythrocyte volume and mean erythrocyte hemoglobin concentration among fish at different treated groups (P>0.05). White blood cell (WBC) counts showed insignificant increase by elevating WB in the diet (P>0.05), whileWBC/RBC ratio increased significantly. Significant increase in the level of total protein, albumin and globulin and albumin/globulin ratio by increasing the concentration of wood betony was observed. Adding wood betony in the diet, could decrease the level of serum triglycerides (Tg.) and cholesterol (Chol.) in comparison to control (P<0.05). Lysozyme activity was significantly enhance in 8ml/kgdietwood betony treated group compared to the control group. After imposing acute stress, serum cortisol and glucose levels, sodium, calcium and potassium of fish fed supplemented wood betonydiet showed significantly lower changes than fish fed the 0% wood betonydiet (P<0.05).The results showed that the extract used in this study has a positive impact on growth parameters, serum biochemical parameters, as well as systemic immune responses to stress
Key words: Wood betony (StachyslavandulaefoliaVahl), Common carp (Cyprinuscarpio), Growth parameters, Hematology indices, acute stress.