Effect of olive meal and supplemental enzymes on performance traits, blood biochemistry, humoral immunity response and caecal microbiota of broilers

This study investigated the growth performance, carcass characteristics, blood biochemistry, humoral immunity and caecal microbiota of broiler chicks fed 0, 2, 4, 6, and 8% olive meal (OM) in diet. In addition, this study investigated the use of enzymatic feed supplements (β-glucanase, phytase and hemicellulase) to enhance digestibility of high fibre diets. At the end of the feeding period (42 days), there were no significant differences among dietary groups on broiler growth performance, including bodyweight (BW) and bodyweight gain (BWG), feed intake (FI), and feed conversion efficiency (FCE). The evaluated carcass traits and meat cuts (breast, drumsticks and wings) did not vary among dietary treatments. Although some minor differences were observed in blood albumin and cholesterol concentrations among groups, the cecum microbiota did not differ in broilers. Antibody titers following vaccinations against infectious bronchitis virus (IBV) and Gumboro disease were higher in birds fed 4% OM. Adding supplemental enzymes to diet had minimal effect on the parameters. Findings from this study support the literature, which suggests that OM is a suitable feed by-product in broiler diets. Moreover, including OM in poultry rations has the potential to provide an economic and environmentally friendly alternative to traditional diets. Finally, the current trial identified that the addition of enzymes was not necessary to achieve optimal productive performance in broiler fed diet containing OM.Keywords: Feed by-product, growth, nutrition, poultr