Mehran Ghaemi - Department of pathobiology, School of veterinary medicine, Shiraz University, Shiraz, Iran
Mohammad-Foad Noorbakhsh - Department of basic science, School of veterinary medicine, Shiraz University, Shiraz, Iran

The current research was conducted to examine the benefits of the administration of Artemisia dracunculus (AD) for the immune system of Rainbow trout (Oncorhynchus mykiss). Gene expression profiles of immune system including IL-۱β and TNFα genes were evaluated by real time RT-PCR tests using TaqMan® probes. Firstly the extract from the aerial parts of AD was prepared. Then, the ingredients of the basal diet and the acquired AD extract were blended in an appropriate concentration to reach four experimental diets with various amounts of AD as follows: with ۰ g (control group, ۰ %), ۱ %, ۲ % and ۳ % of AD plant extracts. Twenty four Rainbow trout (O. mykiss) juvenile, weighing on average ۱۲.۳۸ ± ۰.۱۰ g (mean±SD), were distributed randomly into ۴ groups, fed the experimental diets for ۸ weeks.The gene expression analysis showed that IL-۱β gene expression of the AD treatment groups from ۱% (۱.۶۴ fold) to ۳% (۵.۲۷ fold) is significantly up-regulated but TNFα gene expression is significantly down-regulated from ۱% (۰.۹۳ fold) to ۳% (۰.۱۱ fold). Treating with different amounts of AD extract suppressed TNFα gene expression in rainbow trout which is in agreement with the results of other phenolic phytocompounds treatments. Our result also showed that all concentrations increased IL-۱β gene expression, significantly. More concentrated AD extract treatment, more IL-۱β gene expression. Some phenolic compounds studies showed similar results. From both TNFα and IL-۱β gene expression experiments, this could be concluded that the best concentration of AD extract for rainbow trout treatment is ۲% which significantly up-regulates IL-۱β but not significantly down-regulate TNFα (as an unwanted effect).

Artemisia dracunculus, gene expression, immune system, Rainbow trout, real time RT-PCR