Effect of oregano essential oil on the laying performance and oxidative stabi lity of eggs enriched with polyunsat urated fatt y acids

This study evaluated the inclusion of oregano essential oil (OEO, Lippia origanoides Kunth) in diets enriched with polyunsaturated fatty acids (PUFAs) on productive performance of laying hens, lipid profile and oxidative stability of eggs during storage. 144 hens were distributed in one of four treatments with six replicates in order to evaluate the effect of the type of oil used in the diet (palm or fish) and the inclusion of OEO on the production variables, along with the ethereal extract, lipid profile and malonaldehyde concentration (MDA), using a completely randomized factorial design with the repeated measures of days of storage (0, 30 and 60 days at 4° C). Results show that the type of oil and the OEO did not affect productive performance of layers (P > 0.05). PUFA concentration increased in 16.8% in diets with fish oil in 16.8%, where the DHA also increased by1.4% (P < 0.05), increasing the MDA concentration in egg (MDA 41.6 ng/g yolk), while supplementation of OEO at a level of 100 g/ton improved oxidative stability during storage (MDA 31.1 ng/g yolk). During storage the concentration of MDA in the yolk increased with time reaching 38 ng/g yolk at 60 days. The OEO showed potential as a natural antioxidant in the diet of layers hens improving the oxidative stability of eggs stored at 4°C up to 60 days.