title: Efficacy of semduramicin and salinomycin against Eimeria maxima in a laboratory test using two levels of oocyst inocula.
abstract: The anticoccidial efficacies of semduramicin and salinomycin against five field isolates of Eimeria maxima in broiler chickens were compared in five trials. Uninfected, unmedicated; infected, unmedicated; infected, 25 ppm semduramicin; and infected, 66 ppm salinomycin treatments were assigned to battery cages using a randomized, complete block design. Two levels of inocula, 10(3) and 10(4) oocysts per bird, were used in each trial in the infected treatments, creating a total of seven treatments per trial. Each treatment consisted of five replicate cages of eight broiler cockerels each. Medications were given in the feed continuously for 7 d beginning 24 h before inoculation. Response variables measured included bird weight gain by pen, feed consumption, feed conversion, plasma carotenoid concentrations, and coccidial lesion score. By using two levels of inocula it was demonstrated that the efficacy of each anticoccidial was equal to or greater than 90% in controlling these E. maxima isolates. It was also demonstrated that 25 ppm semduramicin was more efficacious than 66 ppm salinomycin based on improvements in weight gain, feed conversion, plasma carotenoid concentrations, and coccidial lesion control.
authors.affiliation: Animal Health Group, Pfizer Inc., New York, New York 10017, USA.
authors.forename: D P
authors.initials: DP
authors.lastname: Conway
authors.forename: V
authors.initials: V
authors.lastname: Guyonnet
authors.forename: S
authors.initials: S
authors.lastname: Michener
authors.forename: L R
authors.initials: LR
authors.lastname: McDougald
authors.forename: G F
authors.initials: GF
authors.lastname: Mathis
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000592:standards / Q000627:therapeutic use*; D002338:Carotenoids / Q000097:blood; D002645:Chickens / Q000097:blood / Q000469:parasitology* / Q000502:physiology; D003048:Coccidiosis / Q000188:drug therapy / Q000662:veterinary*; D003049:Coccidiostats / Q000592:standards / Q000627:therapeutic use*; D004435:Eating / Q000502:physiology; D004539:Eimeria / Q000187:drug effects* / Q000302:isolation & purification; D008297:Male; D009550:Nigericin / Q000031:analogs & derivatives* / Q000592:standards / Q000627:therapeutic use; D011201:Poultry Diseases / Q000188:drug therapy*; D011714:Pyrans / Q000592:standards / Q000627:therapeutic use*; D015430:Weight Gain / Q000187:drug effects / Q000502:physiology; D000095662:Polyether Polyketides
chemical_list: D000900:Anti-Bacterial Agents; D002338:Carotenoids; D003049:Coccidiostats; D009550:Nigericin; D011714:Pyrans; C010327:salinomycin; D000095662:Polyether Polyketides; C072941:semduramicin