The Efficacy of Monensin2 Against One Sensitive and Thirteen Drug Resistant Strains of Eimeria tenella

ABSTRACT Monensin, admixed with the feed at a level of 0.0125%, adequately protected chickens against experimental infections of Eimeria tenella initiated by a strain that had no previous exposure to drugs as well as by strains resistant to amprolium, arsenosobenzene, buquinoiate, clopidol, decoquinate, glycarbylamide, nequinate, nicarbazin, nitrofurazone, Nova-stat, Trithiadol, Unistat, or zoalene, respectively. When fed to uninfected chickens, monensin did not affect rate of gain to a significant degree in three of four replicates. Moreover, an analysis of the aggregate data did not indicate a significant difference in rate of gain between the uninfected group. POULTRY SCIENCE 53: 770-772, 1974 MONENSIN has been shown to have a broad spectrum of activity against poultry coccidia in battery trials (Shumar