The Effects of Dietary Rosemary (Rosmarinus officinalis L.) Essential Oil Supplementation on Laying Hen Performance, Egg Quality and Oxidative Stability of Egg

This experiment was designed to investigate the effects of rosemary essential oils in various doses on hen performance, egg quality, lipid peroxidation malondialdehyde (MDA) level in fresh and stored egg yolk. The experiment was carried out in random parcel experimental design. In the experiment, 6 groups were formed and each group was divided into 5 replicates. In total 240 Bovans hite laying hens, each replicate included 8 hens, 32 weeks old, were used. Treatment groups were control (Negative Control), 500 mg//kg antibiotic (Positive Control 1), 200 mg/kg vitamin E (Positive Control 2), 100 mg/kg rosemary essential oil, 200 mg/kg rosemary essential oil, 300 mg/kg rosemary essential oil. There was no significant difference in live weight, egg production, egg weight, damaged egg ratio, mortality and egg quality but feed comsumption, feed conversion ratio (FCR) and egg yolk MDA values were affected significantly in between control and treatment groups. At all treatment groups feed comsumption decreased significantly and other groups improved in feed conversion ratio except 500 mg/kg antibiotic and 100 mg/kg rosemary doses groups compared to negative control significantly. 100 mg/kg rosemary essential oil addition during the storage time for 42 and 56 days and 200 mg/kg vitamin E addition for all storage time to ration decreased egg yolk MDA values significantly. As a result, laying birds fed 200 mg/kg vitamin E, and 100 mg/kg of rosemary essential oil additives can use to prevent lipid oxidation.