Physiological and Immunological Effects of Rosemary Essential Oil in Growing Rabbit Diets

Abstract

The efficacy of rosemary essential oil (REO), as feed additive, on growth and blood constituents of growing New Zealand White (NZW) rabbits was evaluated. Thirty six NZW were distributed into four groups: 1 control and 3 treated groups. The control was fed the basal diet, while feeds of other treatments were fortified with 0.25, 0.50 and 0.75 g/kg REO for groups 2, 3 and 4, respectively. The criteria of response were growth performance, carcass traits, blood glucose, plasma lipids, immunoglobulins, total antioxidant capacity (TAC), malondialdehyde (MDA) and testosterone concentrations. Results revealed that REO supplementation had no critical impacts on growth performance, carcass yeild or blood glucose. Rabbits recieving dietary REO exhibited lower lipid profile and higher immunoglobulins A than those of the control. The treated rabbits displayed significantly higher TAC than the basal group with the best reaction for those fed G3 diet. In a similar way, MDA was reduced essentially by including REO. There was a significant increase in testosterone levels due to added REO. The present results indicate that supplemental REO at 0.5 g/kg of diet has a beneficial impact on lipid profile, immunity and antioxidant status of rabbits.