陳進鍾碩士論文中英摘要 草蝦在不同鹽度下之精胺酸需求 研究探討草蝦於三種不同鹽度(8 、16 與 32 ppt)下，必需胺基酸中 精胺酸之需求。以酪蛋白為蛋白源之精製飼料中添加 cellulose acetate phthalate 包衣之精胺酸使濃度為 20、24、28 、32 g/kg diet，各飼料 處理均為三重覆。草蝦初重 0.18±0.03 g，飼養十週後就增重率，以 Broken-line model 計算獲精胺酸需求。結果顯示於 8 ppt 時需求值為 19.37 g/kg diet; 16 ppt 時需求值為21.76 g/kg diet; 而 32 ppt 未得 最適需求，但由文獻已知 28 ppt 時之最適需求為 25 g/kg diet，因此草 蝦精胺酸之需求有隨鹽度提高而增加之趨勢。草蝦血淋巴液之游離精胺酸 濃度在各鹽度處理間並無顯著差異，在各精胺酸添加組中則以24 g/kg diet 組含量高於其他組，肌肉中游離及非游離精胺酸含量在各添加量間並 無顯著差異存在。各組織之精胺酸脢比活性有顯著差異，其中血淋巴液最 高、其次為眼柄、再為肌肉、肝胰臟最低。鹽度及飼料處理並未造成血淋 巴液及肝胰臟之精胺酸脢比活性顯著差異，而眼柄之精胺酸脢比活性在各 鹽度處理下並無顯著差異，但精胺酸添加組則以 20 g/kg diet比活性高於 其他組; 肌肉之精胺酸脢比活性以鹽度 8 ppt 時比活性最高，而各精胺酸 添加組間則無顯著差異。 Arginine Requirements of Juvenile Marine Shrimp Penaeus monodon Reared in Three Salinities This thesis studied the arginine requirement of Penaeus monodon juveniles under three salinities ( 8 ,16 and 32 ppt ). The shrimp were fed for 10 weeks. Casein-based diets containing 4 levels of arginine ( 20, 24, 28 and 32 arginine g/kg diet ) achieved by the supplementation of cellulose acetate phthalate microencapsulated L-arginine . Weight gain were used to quan- tify the arginine requirements. The arginine requirements were estimated to be 19.37 g/kg diet under 8 ppt salinity and 21.76 g/kg diet under 16 ppt based on the broken-line model analysis The growth results under 32 ppt failed to demonstrate an argi- nine requirement. The arginine requirement of the shrimp has been reported to be 25 g/kg diet under 28 ppt salinity.Arginine requirement of Penaeus monodon thus increase with increasing salinity. The shrimp fed the diet containing 24 g/kg arginine showed the highest free arginine concentration in hemolymph. Salinity did not have significant effect on free arginine concentration in hemolymph. Free and protein bound arginine concentration in muscle did not show significant variations in response to arginine supplementation. Arginase activity varied in different tissues with hemolymph, eyestalk,muscle and hepatopancreas in a descending order. Salinity treatments and arginine supplements did not result in significant change in arginase activity in hemolymph and hepatopancreas.Arginase in the group fed diet containing 20 g/kg diet arginine had the highest activities among all groups. The shrimp reared in 8 ppt salinity showed higher arginase activities than those of the other salinity groups.