Effect of dietary supplementation of black cumin (Nigella sativa L.) and cinnamon (Cinnamomum zeylanicum L.) essential oils on performance, egg quality and eggshell bacterial contamination of laying hens

Abstract: The aim of this study was to determine the effects of dietary supplementation of black cumin (Nigella sativa L.) (BCEO) and cinnamon (Cinnamomum zeylanicum L.) essential oils (CEO) on the performance, egg quality and eggshell bacterial contamination of laying hens. A total of 315 Atak-S, 28-weeks-old of age were assigned to three groups with five replicates of 21 hens each for 11 weeks. The trial carried out basal (no supplemented) and 2 treatments black cumin essential oil supplementation and cinnamon essential oil supplementation. During the experiment performance parameters, egg external and internal quality characteristics and eggshell bacterial microbial contamination were measured weekly. At the end of the experiment, CEO supplementation improved feed conversion rate and increased egg shell thickness (P<0.05). Dietary BCEO reduced eggshell Escherichia coli contamination (P<0.05). However there was no significant statistical difference between the experimental groups in terms of feed consumption, egg production, egg weight and other egg internal and external quality characteristics (P>0.05). As a conclusion, we found that the addition of BCEO to the laying hens feed didn't affect the performance and egg quality while the addition of CEO may improve the performance and reduce the egg shell bacteria load. Key words: Black cumin essential oil, cinnamon essential oil, egg quality, shell bacterial contamination, laying hens,