Effects of different levels of savory essential oil in drinking water on performance, some carcass characteristics, immunity and hematology of broiler chicks

This study was carried out to investigate the effects of savory essential oil on performance, some carcass traits, immunity and hematology of broiler chicks. To this aim, 400 Ross 308 male chicks were used in a completely randomized design with 5 treatments and 4 replicates and 20 broiler chicks per experimental unit. Experimental treatments consisted of negative control (without any additive in drinking water), positive control (drinking water containing Orego-Stim) and drinking water containing 100, 200 and 300 mg savory essential oil per liter. The results showed that the addition of all levels of savory essential oil to drinking water of broiler chicks in the first and second weeks of breeding resulted in a significant increase in feed intake. Moreover, at the first weeks use of 100 and 200 mg/lit of savory essential oil significantly improved weight gain and feed conversion ratio in all groups were less than negative control group (P<0.05). Relative weight of liver and abdominal fat was higher in chickens who received 100 mg/lit of savory essential oil in their drinking water than other groups (P<0.05). There was a significant difference among experimental treatments for some blood parameters such as blood lipids, MCH and AST liver enzyme content (P<0.05). The results indicated that the use of savory essential oil in drinking water has had a positive effect on growth performance and feed efficiency of broiler chicks, especially during the early period of rearing.