Eimeria acervulina infection in chicks fed excess copper in the presence or absence of excess dietary methionine.

Five experiments were conducted with young, male, crossbred chicks to investigate the effects of experimental Eimeria acervulina infection on the efficacy of supplemental Cu and (or) methionine when added to a corn-soybean meal diet. Duodenal coccidiosis (due to E. acervulina) and supplemental Cu (500 and 750 mg/kg) depressed weight gain and efficiency of feed utilization. Supplemental Cu increased concentrations of Cu in liver and gallbladder; experimental coccidiosis resulted in a two- to fourfold increase in Cu deposition in these tissues compared with the respective controls. Excess supplemental methionine (.5%) had little effect on Cu toxicity in either healthy or infected chicks. Monensin, an ionophorous coccidiostat, alleviated the coccidiosis-induced Cu deposition.