Adding Ginkgo Biloba leaf extract to the diet as an antioxidant and studying its effect on the productive performance of Ross 308 broilers.

The experiment was carried out in the poultry field of the Department of Animal Production/College of Agriculture/the University of Diyala during the period from 4/9/2021 to 15/10/2021 to study the effect of adding ginkgo leaf extract to broiler diets as an antioxidant and study its impact on the productive performance of birds. This experiment used 225 unsexed hybrid broiler chicks (age: one day). The average weight of the chick was (43.62 g.). Firstly, The chicks were randomly distributed by using five experimental treatments. Each treatment has three replicates (15 birds/repeat). Experimental transactions are as follows. T1 = (control treatment) A standard diet without addition is provided, T2 = standard ratio to which 1 g/kg of Ginkgo Biloba leaf extract is added, T3 = Standard diet to which 2 g/kg of Ginkgo Biloba leaf extract is added, T4 = a standard diet to which 3 g/kg of Ginkgo Biloba leaf extract is added, and T5 = standard ration to which 4 g/kg of Ginkgo Biloba leaf extract is added. The results of the experiment were as follows. The experiment results indicated a significant effect (P≤0.05) when adding different levels of Ginkgo biloba leaf extract to the diets of 308 Ross broilers for 1-42 days. The fourth treatment was superior to the average live body weight during the sixth week and the cumulative weight gain compared to the control. There is a significant superiority (P≤0.05) in the rate of cumulative feed consumption, cumulative feed conversion, efficiency and production index value, where all the addition treatments (1,2,3,4)g/kg feed excelled compared to the control. Keywords: Ginkgo biloba leaves Broiler, Growth performance, Antioxidant activity.