Pathogenicity and control of Eimeria mitis infections in broiler chickens

The pathogenicity of two strains (B4 and C2) of Eimeria mitis was studied using young broiler chickens. Both strains of coccidia were pathogenic, and C2 strain was more virulent than B4. Growth of the broilers was depressed as early as day 3 postinoculation (PI), but the depression was greatest during days 5 and 6 PI. Feed conversion and shank skin pigment of the young broiler chickens were concomitantly affected by infections of E. mitis. Infection subsided by day 7 or 8 PI and was accompanied by a compensatory growth. The drugs effective against the infections were halofuginone, lasalocid, monensin, and nicarbazin. The least efficacious were zoalene and amprolium plus ethopabate.