Ameliorative effect of Psidium guajava essential oil supplemented feed on chicken experimental coccidiosis

Present study investigated the therapeutic efficacy of Psidium guajava essential oil (EO) on chicken experimental coccidiosis in comparison to the diclazuril. Seventy-five 1-day-old Ross 308 broiler chickens were allocated into 5 groups: CEO1: received EO at 1 mg kg^-1 of feed; CEO5: received EO at 5 mg kg^-1 of feed; CT: received diclazuril as standard treatment; CNT: received only basal diet; NC: control chickens; all of the groups except NC were challenged with mixed Eimeria spp. on d14 and received supplemented diet from d1 to d42. Zootechnical records and oocyst per gram (OPG) of feces samples were analyzed on weekly basis. On the last day of the study, blood samples were taken to measure serum concentrations of biochemical parameters and also activities of antioxidant enzymes. β-caryophyllene and α-pinene were determined as major constituents of the EO. On the 3^rd, 4^th, and 5^th weeks, a significant difference was noted in feed conversion ratio (FCR) between CEO1, CEO5, and CT in comparison to NC and CNT chickens (p < 0.05). No significant difference was observed in OPG between CEO1 and CEO5 (p > 0.05); however, CT showed a lower number of OPG relative to EO supplemented groups (p < 0.05). The highest serum activity of glutathione peroxidase was observed in CEO5 which was higher than other groups (p < 0.05). Results of the present study showed that supplementation of P. guajava EO especially at 5 mg kg^-1 of feed may have beneficial effects on prevention of coccidiosis and improvement of health in broilers.