Comparison Study of the Effects of Anthraquinone Extract and Emodin from Rheum officinale Bail on the Physiological Response, Disease Resistance of Megalobrama amblycephala under High Temperature Stress

摘要

In order to evaluate the effects of anthraquinone extract and emodin from Rheum officinale Bail on the physiological response, disease resistance of Megalobrama amblycephala under high temperature stress, fish were randomly divided into three groups: one was the control group, fed with a basal diet, and the other two were the treatment groups, fed with the basal diet supplemented with 0.1% anthraquinone extract or 60 ppm emodin for 8 weeks. The results showed that compared with the control group, the two treatment groups significantly increased serum lysozyme activities, superoxide dismutase activities and the relative HSP70 mRNA levels of liver and reduced serum alanine aminotransferase activities before stress. After 12 h high temperature stress, the two treatment groups significantly increased serum triglycerides contents 6 h after stress, liver superoxide dismutase activities 2 and 6h after stress and the relative HSP70 mRNA levels of liver 2 h after stress compared with the control group. And there are lower in the serum cortisol content 2 and 12 h after stress, serum aspartate aminotransferase activity 12 h after stress and liver malondialdehyde content 6 h after stress in the two treatment groups than those of the control group. Artificial infection with Aeromonas hydrophi1a showed that the cumulative mortality in the control was higher than that of the treatment group. The results suggest that ingestion of supplements with 0.1% anthraquinone extract and 60 ppm emodin can increase immune ability, enhance resistance against high temperature stress and A. hydrophi1a infection.