The study of Immunoster prebiotic effects on biometric factors with emphasis on weight and lenght and differential specification of leukocytes in Caspian sea Rutilus kutum fingerlings

Immunoster prebiotic was studied in 0، 2، 4 percent levels with the purpose of survey of weigh and lenght features and variability of blood leukocytes of Kutum fingerling with initial weight of 0. 35±0. 02gr in a period of 8 weeks. The experiment was performed with use of random design in one control group and two experimental treatments with 3 replicates and with 150 fingerlings in each tank. Feeding was varied from 15% to 20% of fish biomass. At the end of experiment، although weight and length average had no significant difference between control and experimental treatments (P > 0. 05)، but positive and significant difference was observed in differential specification of leukocytes (P ≤ 0. 01). Therefore، by increasing Immunoster levels in diet، the lymphocyte percent increased and respectively the monocyte، neutrophil and eosinophil percent decreased significantly. As، the Immunoster 4% level had highest lymphocyte and least monocyte، neutrophil and eosinophil (P ≤ 0. 01). The obtained results were showed that the study levels of Immunoster prebiotic didn''t have considerable effects on growth performance in Kutum fingerlings، while it was able to play a positive and significant influence as an immunostimulant on blood leukocytes and increasing lymphocyte as an important cellular specific immune index.