AimTo control eight most predominant Eimeria spp. involved in the economic disease of coccidiosis in broiler chicken, by a chemically characterized essential oil of eucalyptus and peppermint. Methods and ResultsThe experimental design consisted of 160day-old-broiler chicks, divided into four equal groups (G(1), G(2), G(3) and G(4)), with 40birds per group. Each group was divided into four equal subgroups. Birds in G(1) were deprived of essential oil treatment and of Eimeria challenge. Birds in G(2) were unchallenged, and administered the essential oil in drinking water at 069mlkg(-1) body weight. Birds in G(3) were untreated with essential oil, and each of its four subgroups was challenged at a different age (14, 21, 28 and 35days). Birds in G(4) were treated with essential oil, and challenged in the same manner as for G(3). Equal number of birds from all subgroups (n=10) were sacrificed at the sixth day after the time allocated for each challenge. The 6day incubation period post challenge resulted in respective mean per cent weight increase in G(2) and G(1) birds equivalent to 578 and 531% (P<005). In addition, the essential oil improved the per cent weight increase in challenged birds (546%) compared to the challenged-untreated birds (186%) (P<005). The mean feed conversion, mortality, intestinal lesion scores and oocyst counts were significantly reduced in the challenged-treated birds compared to the challenged-untreated birds (P<005). ConclusionsThe results support the hypothesis of using the essential oils of eucalyptus and peppermint to control the most prevalent Eimeria spp. involved in coccidiosis of broiler chicken, helping in improvement of their production, alleviation of lesions and reduction in intestinal oocyst counts. Significance and Impact of the StudyThis study provides information about the possibility of using this blend of essential oil as a coccidiostat for the protection of broiler chickens against the prevalent eight Eimeria spp. of coccidiosis.