title: Restoration of sensitivity to salinomycin in Eimeria following 5 flocks of broiler chickens reared in floor-pens using drug programs and vaccination to control coccidiosis.
abstract: Five successive flocks of broilers were reared in floor-pens and given different drug programs or were vaccinated against coccidiosis. Oocysts of Eimeria were isolated from the litter of pens during the fifth flock and their sensitivity to salinomycin (Sal) investigated by measuring new oocyst production following infection of medicated and unmedicated birds. Parasites obtained following 5 flocks given Sal were not well-controlled and it was concluded that they were partially resistant to the drug. Parasites obtained following 4 unmedicated flocks and one medicated flock were better controlled by Sal and it was concluded that in the absence of continuous medication there had been an improvement in drug efficacy. Sal almost completely suppressed oocyst production of isolates from treatments in which medication was followed by vaccination, indicating that when a drug program is followed by vaccination, restoration of sensitivity to Sal had occurred.
authors: Department of Poultry Science, University of Arkansas, Fayetteville 72701 dchapman@uark.edu.
authors: H D
authors: HD
authors: Chapman
authors: Department of Poultry Science, Cornell University, Ithaca NY 14853.
authors: T K
authors: TK
authors: Jeffers
mesh_terms: D000818:Animals; D002645:Chickens; D003048:Coccidiosis / Q000188:drug therapy / Q000469:parasitology / Q000517:prevention & control / Q000662:veterinary*; D003049:Coccidiostats / Q000494:pharmacology; D004351:Drug Resistance; D004539:Eimeria / Q000187:drug effects*; D008297:Male; D033661:Oocysts; D011201:Poultry Diseases / Q000188:drug therapy / Q000469:parasitology* / Q000517:prevention & control; D016052:Protozoan Vaccines / Q000276:immunology*; D011714:Pyrans / Q000494:pharmacology*; D000095662:Polyether Polyketides
chemical_list: D003049:Coccidiostats; D016052:Protozoan Vaccines; D011714:Pyrans; C010327:salinomycin; D000095662:Polyether Polyketides
keywords: Eimeria; anticoccidial drug; broiler; coccidiosis; vaccine