中草药添加剂对热应激虹鳟部分生化指标及激素水平的影响

Effects of Chinese Herb Medicines on Biochemical Indices and Hormone Level of Rainbow Trout Oncorhynchus mykiss Exposed to Heat Stress

将平均体质量(30±5)g的虹鳟Oncorhynchus mykiss饲养在循环水族箱(0.90m×0.50m×0.45m)中,投喂添加柴胡(18g或12g/50kg体质量)、藿香(15g或9g/50kg体质量)和茵陈(20g或30g/50kg体质量)水煎剂制成的药饵15d后,在水温15℃、缓慢升温至20℃和25℃下尾静脉采血,测定血浆中皮质醇(COR)和肾上腺素(E)的含量及肝脏中酸性磷酸酶(ACP)和碱性磷酸酶(ALP)的活性,观察肝脏组织病理切片,探究中草药对虹鳟抗热应激能力的影响。结果显示,在热应激期间,低浓度藿香组鱼血浆中皮质醇含量高于对照组(P<0.05);20℃和25℃持续升温后,高浓度藿香组血浆中肾上腺素含量高于对照组,藿香组肝脏中酸性磷酸酶活性高于对照组(P<0.05)。在热应激期间,柴胡组和藿香组肝脏中碱性磷酸酶活性变化不明显(P<0.05)。20℃时虹鳟肝脏开始出现病变,随着水温升高,肝脏组织结构破坏严重,中草药组缓解了虹鳟肝脏组织受热应激的影响。25℃持续升温后,藿香组鱼肝脏组织的破坏程度最小,表明藿香能有效缓解热应激对肝脏的损伤,提高虹鳟抗热应激能力。

Rainbow trout Oncorhynchus mykiss with body weight of(30±5)g were reared in circulating aquarium tanks and fed diets containing Chinese herbal medicines Bupleurum chinensis(18 g or 12 g/50 kg body weight),Agastache rugosa(15 g or 9 g/50 kg body weight)and Artemisiae capillaris(20 g or 30 g/50 kg body weight)for 15 d.Then the blood was sampled from caudal veins of the rainbow trout exposed to water temperature of 15℃,slowly rising to 20℃and 25℃to examine contents of cortisol(COR)and adrenaline(E)in plasma and the activities of acid phosphatase(ACP)and alkaline phosphatase(ALP)in liver and to observe the liver histopathological sections to evaluate the effects of Chinese herb medicines on liver biochemical indices and hormone level of rainbow trout exposed to heat-stress.There was higher level of cortisol in plasma in the low concentration group of Agastache rugosa than that in the control group,the higher level of plasma adrenaline in the high concentration group of Agastache rugosa than in the control group(P<0.05),continuous warming at 20℃and 25℃.At the same time,the activities of liver acid phosphatase were found to be higher in the group of Agastache rugosa than in the control group(P<0.05),without significant difference in the activities of liver ALP in the group of Bupleurum chinensis and the group of Agastache rugosa in the whole heat-stress period.Pathological changes were first observed in the liver of rainbow trout at 20℃.The damaged liver tissue of rainbow trout was seriously as the water temperature became higher and alleviated in the groups of Chinese herbal medicines under heat-stress,with the minimal liver damage in the group of Agastache rugosa at continuous rising temperature of 25℃.In summary,Agastache rugosa effectively alleviates the damage of liver in rainbow trout than the other Chinese herbal medicines do and is used as candidates for anti-thermal stress Chinese herbal additives.