Abstract: Effects of three Chinese medicinal herb complex additives(Cyrtomium fortunei,prescription I and prescription II) aqueous extract on the contents of active material and the activities of enzymes related to antioxidation in 1+ age old Amur sturgeon(Acipenser schrencki Brandt) by oral perfusion.The Amur sturgeon juveniles with body weight of 0.08±0.10 kg were cultured in aquaria of each 0.90 m×0.50 m×0.45 m at water temperature of 22℃ for 2 weeks and then were orally administrated by Cyrtomium fortunei,prescription I and prescription II at a dose of 9,17.5 and 36 g·50 kg-1 body weight once a day for 14 days,respectively,oral distilled water as the control.After 14 day administration,some test fish were stimulated for two hours at high temperature(30℃),and then all sampled together to analyze the activities of superoxide dismutase(SOD),nitric oxide synthase(NOS) and the contents of malonaldehyde(MDA) and nitric oxide(NO).The three prescriptions were shown to play a certain role in improvement of antioxidation in Amur sturgeon.Cyrtomium fortune additive led to increase in activity of SOD in several tissues of Amur sturgeon and to promote a rapid response of fish under the thermal stimulation.Although Cyrtomium fortune showed decrease in the content of MDA,it had a certain influence on liver antioxidation.Therefore it should be administered properly and the optimum administration modalities were required.The decrease in content of MDA was observed in the body of the fish administrated by Prescription I and improvement of a rapid response of the fish administrated by Prescription I to the thermal stimulation.Prescription II had a better performance in antioxidation,but did not show any effects on high temperature stimulation.

Key words: Chinese medicinal herb complex additive, Acipenser schrencki, SOD, MDA, NO, NOS