Impact of Diets Containing Olive Cake and Herbs on Growth Performance and Carcass Traits of Broiler Chicken Through Growing Stage

&lt;b&gt;Background and Objective:&lt;/b&gt; Olive cake, a by-product of olive oil extraction, is a sustainable, protein-rich ingredient that enhances poultry growth and profitability. It is cost-effective and valuable in modern poultry nutrition programs. So, this study investigated the impact of the fermentation process of olive cake and its usage to replace yellow corn with or without adding herbal additives in broiler diets on growth performance, carcass characteristics and blood parameters. &lt;b&gt;Materials and Methods:&lt;/b&gt; At 21 days of age, 600 unisex chicks of the Sasso breed were distributed among 60 groups of 10 birds each. Using an utterly randomized approach, five treatments with twelve replicates of ten birds each were dispersed in a 2×2×2 factorial arrangement. Two varieties of olive cake (fermented, with and without herbal mixture) and two olive cake levels (20 and 30% in diet substituted with yellow corn) are used as treatments. Growth performance, blood parameters, carcass characteristics and meat quality were measured at a significant level of 0.05 using a one-way ANOVA model. &lt;b&gt;Results:&lt;/b&gt; The increasing olive cake (OC) in poultry diets reduced feed consumption, with the 30% OC herbal mixture showing the least intake (p<0.05). Significant variations were found in the feed conversion ratio (FCR) among treatments, but OC did not affect organ weights. While, liver percentage was significantly impacted, blood parameters like triglycerides and cholesterol showed no significant differences, except for reduced total cholesterol in OC-fed broilers. The OC addition in poultry rations presents a cost-effective alternative to traditional diets. &lt;b&gt;Conclusion:&lt;/b&gt; Using unconsumed olive waste as poultry feed additives can reduce feed costs, improve broiler growth and decrease environmental pollution. This approach offers an economical and sustainable solution amid rising feed prices and competition.