In order to investigate the effects of Organomin-Forte on the performance, antioxidant status and immune response of laying hens, an experiment was carried out using two hundred White Leghorn W36 laying hens (55 weeks old) in a completely randomized design manner with 2 experimental treatments, 5 replicates and 20 hens per replicate. Experimental treatments were 1: control and 2: Organomin-Forte (0.035%), which were fed to hens for 3 periods of two weeks each and 42 days in total. Organomin-Forte was into the diet along with existing inorganic mineral sources. Data on all studied parameters were recorded, calculated and presented at the end of the each period. Results showed that using Organomin-Forte improved the overall performance traits including feed conversion ratio, egg weight, egg quality, shell weight and egg specific gravity and serum oxidant activities such as glutathione peroxidase, superoxide dismutase, vitamin E and selenium compared to control group, significantly (P<0.05). Based on the obtained results, application of Organoimin-Forte can be recommended in the diet of commercial laying hens.
