The Effect of Nutritional Levels of Valerian and Oregano oil on Interferon Gamma Gene Expression in Broiler Chickens

The use of medicinal plants instead of antibiotics is highly effective in preventing and treating many diseases of livestock and poultry due to their multiple properties. In this study, gene expression changes of IFNγ were evaluated with the addition of Valerian and oregano oil in Arian broilers. The experiment was conducted in a completely randomized design with 7 treatments and 4 replications. Experimental treatments included control, antibiotic, probiotic, Valerian oil and oregano oil at levels of 200 and 400 mg/kg. Body weight traits at 6 weeks, feed rate, feed conversion ratio and IFNγ gene expression were measured. To determine the expression of IFNγ gene, the total RNA was extracted from four hepatocyte repeat lymphocytes of different treatments and, after generating the cDNAs of the samples, the expression of the genes was investigated by Semi-Quantitative RT-PCR. To investigate the effect of experimental treatments on traits and compare the mean of treatments with GLM and Duncan test (p <0.05), SAS software (9) was used. The results were analyzed using GLM software (SAS 9) and the mean of the treatments were compared using Duncan test. The results showed that expression of IFNγ gene was significantly different at different levels of treatment, so that it was the highest at 400 mg/kg and the lowest amount of expression was observed in treatment of oregano oil (200 mg/kg). In general, the results of this study showed that the use of oregano oil in broiler chicken diet improves immune function and decreases mortality rate.