LAUSR

Abstract A total of 480 one-day-old male broiler chickens were used in a 42-d study to assess the effects of different inclusion levels of lavender essential oil (LEO) supplementation in comparison with an antibiotic growth promoter on growth performance and physiological characteristics of broiler chickens. On d 1, broiler chickens were randomly assigned into 4 experimental treatments (6 replicates of 20 broiler chickens each) including a basal diet without any additive (control, CON), the basal diet supplemented with 200 mg/kg virginiamycin (VIM), and the basal diet supplemented with either 300 (LEO300) or 600 (LEO600) mg/kg LEO. The results showed that experimental treatments had no significant effect on feed intake at any stage of the study. In addition, no effect of experimental treatments was observed on body weight gain (BWG) and feed conversion ratio (FCR) over the starter period (d 0–21). However, broiler chickens fed diets supplemented with LEO600 and VIM had greater BWG and exhibited a lower FCR during grower (d 21–42) and the entire production period (d 0–42; P