THE EFFECTS OF JADE SCREEN POWER ON THE NON-SPECIFIC IMMUNE RESPONSE AND THE EXPRESSION OF THE RELATED GENES IN FISH

In this study, we investigated the effects of Jade screen powder on the non-specific immune response and the expression of the related genes in tilapia(Oreochromis niloticus) as well as the effects on the resistance to the infection in grass carps. In order to explore the bio-activity of traditional Chinese herb Jade screen powder on aquaculture, the fish was fed with the four groups of diets supplemented with Chinese herbs(2.5%, 5%, 10% Jade screen powder and 1% Qishen powder) for 2 weeks. For tilapia, all four Chinese herb groups exhibited increase in the rate of the body weight gain, and 10% Jade screen powder had the most significant effect. There was no difference in the index of liver, kidney, spleen and in the haematological parameters between the treated groups and the control. Compared to the control group, the levels of AST and ALT were lower in the treated groups, but the level of AKP in the 2.5% and 10% Jade screen powder groups and 1% Qishen powder group was higher. There was an insignificant increase in the activity of the serum lysozyme in tilapia treated with jade screen powder at all three concentrations. Moreover, the activity of plasma lysozyme increased significantly in the group fed with 2.5% Jade screen powder compared to the control(P0.05). The herbal treatment also insignificantly elevated the production of ROS(reactive oxygen species)(P0.05). The expression of HSP70 was affected by the herbal treatments in a tissue-specific pattern:it was up-regulated in the liver, and in the kidney 2.5% and 5% Jade screen powder boosted the expression, however the expression was down-regulated in the spleen. The expression of TGFRⅢ was also differently regulated by the herbs in various organs:2.5% Jade screen powder up-regulated the expression in the liver and the kidney, and 1% Qishen powder also had a stimulating effect in the kidney, and the expression could be enhanced by all treatments in spleen. Jade screen powder improved the resistance to the infection of Aeromonas hydrophila in grass carps, which was represented by the lower mortality rate and less bacteria in the blood, and 5% Jade screen powder was especially effective. These results suggested that Jade screen powder may improve the growth, the non-specific immune response and the expression of related genes in tilapia.