title: Residual activity of anticoccidial drugs in chickens after withdrawal of medicated feeds.
abstract: Seven anticoccidial drugs commonly used in poultry (diclazuri), monensin, salinomycin, halofuginone, nicarbazin, robenidine, amprolium, and lasalocid) were tested for residual activity after withdrawal. In each test, the products were given at the recommended level to cages of 10 broiler chickens. Oral inoculation with coccidia was given after withdrawal of medication. Birds pretreated with 1 ppm of diclazuril and inoculated with Eimeria tenella after drug withdrawal had normal weight gain and very low lesion scores. Residual activity depleted gradually over several days, as shown by higher lesion scores when medication was withdrawn for up to 3 days before inoculation. Similar results were observed when young birds were inoculated with a mixture of E. tenella, E. maxima and E. acervulina, and also when birds were given diclazuril to market weight (6 weeks of age) and inoculated with a mixture of six species of Eiméria (The above species plus E. brunetti, E. mitis, and E. necatrix) after withdrawal of medication for 2 days. In contrast, there was no evidence of residual anticoccidial activity with nicarbazin, halofuginone, lasalocid, amprolium, salinomycin or monensin. Overall, the residual activity was unique to diclazuril.
authors.affiliation: Department of Poultry Science, University of Georgia, Athens 30602, USA. lrmcdoug@uga.cc.uga.edu
authors.forename: L R
authors.initials: LR
authors.lastname: McDougald
authors.forename: B P
authors.initials: BP
authors.lastname: Seibert
mesh_terms: D000670:Amprolium / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D000821:Animal Feed; D000818:Animals; D002645:Chickens / Q000378:metabolism / Q000469:parasitology*; D003048:Coccidiosis / Q000517:prevention & control / Q000662:veterinary*; D003049:Coccidiostats / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D016786:Eimeria tenella / Q000187:drug effects*; D005243:Feces / Q000737:chemistry; D005260:Female; D007832:Lasalocid / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D008297:Male; D008985:Monensin / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D009528:Nicarbazin / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D009570:Nitriles / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D010880:Piperidines; D011201:Poultry Diseases / Q000517:prevention & control*; D011714:Pyrans / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D011799:Quinazolines / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D052999:Quinazolinones; D011897:Random Allocation; D014227:Triazines / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D000095662:Polyether Polyketides
chemical_list: D000670:Amprolium; D003049:Coccidiostats; D007832:Lasalocid; D008985:Monensin; D009528:Nicarbazin; D009570:Nitriles; D010880:Piperidines; D011714:Pyrans; D011799:Quinazolines; D052999:Quinazolinones; D014227:Triazines; C010327:salinomycin; D000095662:Polyether Polyketides; C057884:diclazuril; C010176:halofuginone