Roxarsone: Efficacy Against Eimeria brunetti Infections in Chickens

Roxarsone (3-nitro-4-hydroxyphenylarsonic acid) as a feed additive at 0.005% improved growth rate and feed efficiency while reducing macroscopic lesion scores and mortality in broiler chickens. Each bird was inoculated with 200,000 oocysts of Eimeria brunetti in two laboratory experiments. Addition of roxarsone to amprolium+ethopabate or zoalene improved the control of E. brunetti infection. These results establish efficacy of roxarsone in control of E. brunetti. Use of roxarsone in feed of uninoculated birds produced no differences compared to unmedicated controls in weights or feed conversions.