The efficacy of using olive cake as a by-product and probiotic supplementation on growth performance and blood characteristics of broiler chickens

Olive cake has high nutritional content, which can be used as a protein and fat sources in poultry diets. The main aim of the work was to determine the impact of using different levels of Olive cake as food processing by-products and probiotics in a broiler diets and their efficacy on growth performance and blood characteristics. In the feeding experiment, 336-day-old male broiler chicks (Ross 308) were raised for 42 days. They were randomly divided into seven designed groups experimentally; each included four replicates and 12 chicks. The dietary treatments were as follows; Basal diet without Olive cake (T1), Basal diet with (4%, 8% and 12%) olive cake for (T2, T3 and T4), respectively, and Basal diet with (4%, 8% and 12%) Olive cake + 0.4 g/kg Iraqi probiotic for (T5, T6 and T7), respectively. The results indicated that 4% OC with 0.4 g/kg probiotic showed the highest, live body weight, body weight gain, European Production Efficacy Factor and improved Feed conversion ratio at the end of the experiment. Also, the supplementation of Olive cake with or without probiotics substantially increased lymphocyte numbers, lowered Heterophil/Lymphocyte (H/L) ratio and decreased cholesterol levels compared to the control group at the end of the bird’s life. Also, haematological and biochemical parameters significantly (P<0.05) were improved when 4% Olive cake 0.4 g/kg probiotic was added to the diet of broilers. In conclusion, Olive cake and probiotic supplementation had a positive impact on chicken performance and blood characteristics of broilers.