橡胶籽油替代豆油对丝尾鳠幼鱼生长性能、消化酶活性和抗氧化功能的影响

旨在研究饲料中橡胶籽油替代豆油对丝尾鳠幼鱼生长性能、消化酶活性和抗氧化功能的影响，并确定其适宜替代比例。以橡胶籽油分别替代0%(R0)、25%(R25)、50%(R50)、75%(R75)和100%(R100)豆油，配制5种等氮等能饲料，进行8周饲养试验。试验表明：（1）R25替代组体增重和日增重系数均显著高于其他处理组(P?0.05)；（2）R25、R50和R75替代组肠道脂肪酶活性显著高于R100替代组；R25替代组肝脏胰蛋白酶活性显著高于其他处理组；类似地，R25替代组肝脏脂肪酶活性显著高于R75和R100替代组；（3）随着橡胶籽油替代豆油比例的提高，肝脏ALT、AST和GGT活性呈先上升后下降趋势，其中以R25替代组最高；R100替代组肝脏GDH活性显著低于R0组；（4）R100替代组血浆POD活性显著低于R50和R75替代组；类似地，R100替代组血浆T-AOC活性显著低于R25和R75替代组；R100替代组肝脏MDA含量显著高于其他处理组。结果表明，橡胶籽油替代25%~75%豆油对丝尾鳠饲料利用率和抗氧化功能均无明显负面影响，且替代25%明显提高丝尾鳠生长性能；但完全替代明显抑制丝尾鳠抗氧化功能。

Replacing Soybean Oil with Rubber Seed Oil Affects Growth Performance, Digestive Enzyme Activity and Antioxidant Capacity of Asian Red-tailed Catfish (Hemibagrus wyckioides)

This study aims at investigating the effects of replacing soybean oil with rubber seed oil on growth performance, digestive enzyme activity and antioxidant capacity of Asian red- tailed catfish (Hemibagrus wyckioides), and determining the appropriate replacement rate of soybean oil by rubber seed oil. Five isoproteic and isolipidic experimental diets (R0, R25, R50, R75 and R100) were formulated with rubber seed oil replacing 0%, 25%, 50%, 75% and 100% soybean oil in diets, respectively. The feeding trial lasted for 8 weeks. The results showed that: (1) the weight gain and daily gain coefficient of fish fed R25 diet were significantly higher than that of the other diets (P<0.05); (2) the intestinal lipase activity was higher in R25, R50 and R75 diets, compared to R100 diet; the intestinal trypsin activity of R25 diet was significantly higher than that of the other diets; similarly, the hepatic lipase activity was higher in R25 diet compared with fish fed R75 and R100 diets; (3) with the increasing of rubber seed oil replacement level, the hepatic alanine transaminase, aspartate transaminase and glutamyl transpeptidase activities firstly increased and then decreased, the highest values were observed in R25 diet; the hepatic glutamate dehydrogenase activity of R100 diet was significantly lower than that of R0 diet; (4) the plasma peroxidase of R100 diet was significantly lower than that in R25 and R75 diets; similarly, the plasma total antioxidant capacity of R100 diet was significantly lower than that of R25 and R75 diets; the hepatic malondialdehyde content was significantly higher in R100 diet compared with fish fed the other diets. These results indicate that replacing 25%-75% soybean oil with rubber seed oil has no obvious negative effect on feed utilization and antioxidant capacity, and replacing 25% soybean oil is beneficial to improve the growth performance, but total replacement markedly depresses the antioxidant capacity of Hemibagrus wyckioides.