Effect of Dietary Inclusion of Olive Leaves and Olive Pulp on the Oxidative Status and Meat Quality of Broiler Chickens

The production of olive oil results in various by-products such as olive leaves and olive pulp, which can be utilized in animal nutrition. The aim of the present study was to investigate the effects of dietary olive leaves and olive pulp on the oxidative status and fatty acid (FA) composition of broiler breast meat. A total of 120 one-day-old male Ross 308 broilers were randomly divided into 5 experimental groups: 1 control group (Cont) without supplementation and 4 experimental groups supplemented with either 5% or 10% olive leaves (OLeav5; OLeav10) or olive pulp (OPulp5; OPulp10). Blood and breast muscle samples were taken at the end of the experiment. The results showed that the addition of olive leaves or olive pulp did not significantly alter the concentration of malondialdehyde (MDA) and the antioxidant capacity of lipid-soluble compounds (ACL) in the blood or the enzyme activities of the liver. However, the antioxidant capacity of water-soluble compounds (ACW) in serum was reduced in broilers receiving 5% olive pulp or 10% olive leaves (p = 0.002). In addition, meat quality parameters were not affected by olive leaves or pulp intake, although 10% olive leaves reduced lightness (L*) (p = 0.023) and α-tocopherol concentration in breast muscle (p = 0.001) compared to control. Olive leaves and pulp intake also affected the FA profile of the breast muscle, with 5% olive pulp increasing monounsaturated fatty acid (MUFA) content (p = 0.002), while 10% olive leaves increased polyunsaturated fatty acid (PUFA) content (p = 0.015). In conclusion, supplementation with up to 5% olive leaves or pulp had no adverse effects on the oxidative status and meat quality of broilers.