Effect Of Se, Co And Mn Supplemented In The Formulated Diets On Immune Function Of Penaeus Vannamei In Different Grow Periods

In order to discuss the mineral requirement of Penaeus vannamei in different grow period for keeping immune function under normal state, we study the effect of Selenium(Se), Cobalt(Co) andmanganese(Mn) supplemented respectively in the formulated diets on immune function of Penaeus vannamei in different grow periods. Thedoses of Se is designed to 0 mg/kg , 0.2 mg/kg, 0.4 mg/kg, 0.8 mg/kg , 1.6 mg/kg and 3. 2mg/kg. The doses of Co is designed to 0 mg/kg , 25 mg/kg , 50 mg/kg , 75 mg/kg , 150 mg/kg and 300 mg/kg.The doses of Mn is designed to 0 mg/kg , 20 mg/kg , 40 mg/kg , 80 mg/kg , 120 mg/kg and 160 mg/kg. Active of AKP , SOD , GSH-Pxand LSA are measured at different states.Firstly, we study the effect of Se , Co and Mn supplemented respectively in the formulated diets on immune function of Penaeus vannamei whose length is l~5cm. The index of immunity is measured atthe 0 day, the 7th day , the 14th day and the 21th day. The result shows that the three minerals has respectively positive effect on the immunity of Penaeus vannamei. Active of enzymes is enhancedsignificantly when the dose of Se is 0.2 mg/kg, the dose of Co is 25 mg/kg and the dose of Mn is 20 mg/kg. The active of enzymes oflow dose groups rise up, which remains stable level at the 21th day. However , the active of enzymes of high does groups increases at the 7th day and then declines at the 14th day.Secondly, we study the effect of Se , Co and Mn supplemented respectively in the formulated diets on immune function of Penaeus vannamei whose length is 5-8cm. index of immunity was measured at the day 0 , the 7th day, the 14th day and the 21th day. The result shows that the three minerals has respectively positive effect onthe immunity of Penaeus vannamei. active of enzymes were the mostsignificant enhanced among of dose of Se is 0.4 mg/kg, Co is 50 mg/kg and Mn is 40 mg/kg. The active of enzymes of Proper doesgroups rise up after a week , which further enhanced at the 14thday , and remained high level at the 21th day. However, the active of enzymes of high does groups increases at the 7th day and thendelcines at the 14th day.Thirdly, we study the effect of Se , Co and Mn supplemented respectively in the formulated diets on immune function of Penaeus vannamei whose length is 8-10cm. Index of immunity was measured atthe 0 day, the 7th day, the 14th day and the 21th day. The result shows that the three minerals have respectively positive effect on the immunity of Penaeus vannamei. Active of enzymes were the most significant enhanced when the dose of Se is 0. 4-0. 8mg/kg , that of Co is 50-75mg/kg and that of Mn is 120 mg/kg. Proper doses' groupshold high level of active of enzymes at different stages and keeps stable after 21days. However , the active of enzymes of lower andhigher does groups has decreased after some time(7days or 14 days) ,some of which are even lower than those of non-supplement group.Finally, we study the effect of Se , Co and Mn supplemented respectively in the formulated diets on immune function of Penaeus vannamei whose length is over 10cm. Index of immunity was measured at the 0 day , the 7th day, the day 14th and the day 21th. Theresult shows that the three minerals have respectively positive effect on the immunity of Penaeus vannamei. Active of enzymes were the most significant enhanced among of dose of Se is 1. 6-3.2mg/kg , Co is 150mg/kg and Mn is 120mg/kg. The active of enzymes of Proper dose groups remains high level at different stage. However , the active of enzymes of lower and higher dose groups usually havealready decreased after some time(7days or 14days) , some of whichare even lower than those of non-supplement group.In conclusion , during growing of Penaeus vannamei , the mineral requirement of Se , Co and Mn for keeping the best immune function of shrimp increases as soon as the length increases.