effect of anise seed (pimpinella anisum l.) on performance, immune system, antioxidant activity and blood estrogen level in broiler chickens

this study was carried out to evaluate the effect of different levels of anise seed on the performance, immune system, antioxidant activity and blood estrogen level of broiler chicks. a total of 192 day -old ross 308 broilers were trained for 42 days in a completely randomized design with four treatments, four replicates and 12 birds per each replicate. treatments were included the levels of zero (control(, 0.3, 0.6 and 0.9 percent of anise seed in diet. srbc was injected at day 28 and blood samples were collected from chickens at days 35 and 42 of rearing. dietary anise supplementation had no positive effect on feed intake and weight gain of broilers. in starter period, the chicks fed by 0.3 percent of anise seed, had the least feed conversion ratio (p