本试验旨在研究饲料中不同水平的铜和维生素C交互作用对花鲈生长性能、肝脏铜积累量及免疫功能的影响。饲料设计适量(3.5 mg/kg)和高量(35 mg/kg)2个铜水平,3个维生素C添加水平(50、500和1 000 mg/kg),采用2×3交互设计,配制成6种等氮、等能的饲料用于各试验组,各组分别为S50、S500、S1000、H50、H500和H1000,每组3个重复,每个重复30尾鱼。试验周期为6周。结果表明:1)S500组花鲈的末重和特定生长率显著高于S1000组(P〈0.05);S500、H50组肥满度显著高于S50组(P〈0.05)。2)高铜组的肝脏铜积累量显著高于适铜组(P〈0.05);交互作用下,高铜组显著高于S1000组(P〈0.05)。3)高铜组肝脏中C3含量显著低于适铜组(P〈0.10),交互作用下,H50组显著低于S50组(P〈0.10);S500组肝脏钠钾三磷酸腺苷酶活性最高,显著高于H1000组(P〈0.10);S500组肝脏碱性磷酸酶(AKP)活性最高,交互作用下,显著高于S50组(P〈0.10);适铜组的丙二醛(MDA)含量显著高于高铜组(P〈0.10)。结果提示,花鲈饲料中添加3.5 mg/kg铜和500 mg/kg维生素C时,鱼体生长性能最好,肝脏的铜积累量较低,免疫功能得到提高。
This experiment was conducted to evaluate the effects of dietary copper-vitamin C interaction on growth performance,copper accumulation in the liver and immune function of Lateolabrax japonicus.Six isoenergetic and isonitrogenous semi-purified diets were prepared according to a 2×3 interaction design,which included 2 copper levels [proper(3.5 mg/kg) and high(35 mg/kg)],and 3 vitamin C levels(50,500 and 1 000 mg/kg).The experimental groups were S50,S500,S1000,H50,H500 and H1000,which had 3 replicates per group and 30 fish per replicate.The experiment lasted for 6 weeks.The results showed as follows: 1) the final weight and specific growth rate(SGR) of group S500 were significantly higher than those of group S1000(P0.05);the condition factors(CF) of groups S500 and H50 were significantly higher than that of groups S50(P0.05).2) The copper accumulations in the liver of high copper level groups were significantly higher than those of proper level groups(P0.05),and were significantly higher than those of group S1000 under interaction(P0.05).3) The complement 3(C3) content in the liver of high copper level groups was significantly lower than that of proper copper level groups(P0.10),and that of group H50 was significantly lower than that of group S50 under interaction(P0.10);the liver Na+-K+-ATPase activity of group S500 was the highest,and was significantly higher than that of group H1000(P0.10);the liver alkaline phosphatase(AKP) activity of group S500 was the highest,and was significantly higher than that of group S50 under interaction(P0.10);the malonaldehyde(MDA) content of proper copper level groups was significantly higher than that of high copper level groups(P0.10).The results indicate that fish with the supplementation of copper at 3.5 mg/kg and vitamin C at 500 mg/kg in diet have the best growth performance and the lower copper accumulation in the liver,the immune function is also improved.