Efficacy of Various Drugs for the Prevention of Experimentally Induced Coccidiosis in Chickens

THE use of coccidiostats in poultry feeds continues to be an important factor in the development of the poultry industry. The efficacy of certain drugs for prevention or control of coccidiosis has been reported by many workers including Peterson (1960) and Morrison et al. (1961) and is continually tested under field conditions. Recently buquinolate* (ethyl 4-hydroxy-6,7-diisobutoxy-3-quinolene-carboxylate), hereafter referred to as BA, has been reported to be efficacious against 5 pathogenic species of Eimeria: E. tenella, E. necatrix, E. maxima, E. acervulina, and E. brunetti. BA in the feed at 0.00825% prevented mortality from coccidiosis and permitted superior weight gains (Johnson and Porter, 1966). Because Amprolium 0.0125% plus ethopabate 0.0004% (AE) and 3,5-dinitroo-toluamide 0.0125% (Zoalene) have been used for several years as effective coccidio-stats in the field, these drugs were used for comparative purposes in this study. Battery trials with strains of Eimeria and a floor pen trial were conducted. The …