Anticoccidial efficacy of salinomycin (AHR-3096C) and compatibility with roxarsone in floor-pen experiments with broilers.

Five experiments were conducted to test the anticoccidial efficacy of salinomycin (AHR-3096C, A. H. Robins) at 66 ppm and its compatibility with roxarsone (50 ppm) under floor pen conditions Monensin (100, 121 ppm), lasalocid (75, 125 ppm), and shuttle programs of salinomycin-monensin (66/100 ppm) or monensin-salinomycin (100/66 ppm) were included for comparison. Coccidiosis exposure was provided by using the infected seeder bird technique. Salinomycin reduced the lesion scores significantly and improved the body weight and feed conversion in all the trials as compared to unmedicated groups. All three ionophores effectively reduced the lesion scores. Birds treated with salinomycin-monensin shuttle programs had lesion scores, body weight, and feed conversion that were not significantly different from the salinomycin treated birds, suggesting that this shuttle program could be used satisfactorily for control of coccidiosis. Lesion scores, body weight, and feed conversion data of the 4th and 5th trials suggested that the anticoccidial activity of salinomycin and roxarsone are additive. There was evidence of compensatory growth after withdrawal of salinomycin and monensin but not with lasalocid.