Effect of herbal mixture supplementation to fish oiled layer diets on lipid oxidation of egg yolk, hen performance and egg quality

In this study, the effects of a specific herbal mixture as a feed additive in layer diets which are enriched with omega-3 fatty acids by fish oil on egg yolk lipid oxidation, hen performance and egg quality were investigated. A total of 140 Lohmann white 34 week old hens were divided into four groups and the study was carried out 16 weeks. Negative control diet was not included supplemental oil, herbal mixture and synthetic antioxidant (NC); fish oiled control diet (FOC) was involved fish oil (1.5 %) and soy oil (1.5 %) but herbal mixture and synthetic antioxidants free; herbal mixture diet was formulated as of FOC diet + herbal mixture [Origanum Vulgare (dried leaf), Thymus Vulgaris (dried leaf), Thyme Oil, Origanum Oil, Garlic Oil, Anise Oil and Fennel Oil] (FOHM) and synthetic antioxidant diet (FOSA) was prepared with FOC diet + synthetic antioxidants (ethoxyquine, butylhydroxitoluene, butylhydroxianisole and citric acid). Egg production, feed conversion ratio, feed consumption egg weight, eggshell breaking strength and haugh unit were not affected by the dietary treatments. There were no significant differences between egg yolk MDA values of NC and FOC until 42(th) storage day (+4 degrees C) but MDA values in egg yolk of FOC was higher(p < 0.05) than NC's after 42(th) storage day. Addition of herbal mixture and synthetic antioxidant separately to FOC' diet reduced egg yolk MDA values during 56 days storage period even if it is in the first day (p < 0.05). According to these data, addition of herbal mixtures to fish oiled layer diets instead of synthetic antioxidants can be a natural method to prevent egg yolk from oxidation