piperidines and diclazuril

Following IV injection of doxycycline in a dose of 20 mg kg(-1) b.wt., its serum concentration was best fitted in two-compartment open model in chickens fed either on control or on anticoccidials-containing rations. Diclazuril and halofuginone resulted in a significant short distribution half-life (t(½α)) (7.17±0.39 and 11.88±1.05 min, respectively) and increased total body clearance (Cl(tot)) 0.37±0.024 and 0.295±0.034 L/kg/h, respectively. Following oral dosing the tested drug absorbed with t(½ab) of 41.38±1.6, 17.48±0.86 and 41.83±1.8 min, respectively and their C(max) values (3.18±0.18, 5.425±0.48 and 0.986±0.037 μg/ml) were attained at 2.07±0.097, 1.403±0.074 and 2.55±0.106 h. For doxycycline alone and in presence of diclazuril and halofuginone, respectively. Systemic bioavailability was 22.64±3.46, 86.74±9.23 and 22.38±3.09%, respectively. Following IM injection t(½ab) were 9.096±1.34 for doxycycline alone, 16.24±2.21 and 15.6±1.7 min in the presence of diclazuril and halofuginone, respectively. C(max) was 3.10±0.28, 4.63±0.57 and 0.55±0.07 μg/ml reached at 0.8±0.083, 1.13±0.126 and 1.21±0.105 h. For the antibiotic alone, and in presence of either diclazuril and halofuginone, respectively. Systemic bioavailability was 22.41±3.86, 88.97±12.9 and 12.31±0.99% in chickens fed on anticoccidial-free, diclazuril- and halofuginone-containing rations, respectively. Both the tested anticoccidials induced higher doxycycline tissue residues in all tested tissue samples.

Topics: Animal Feed; Animals; Anti-Bacterial Agents; Chickens; Coccidiosis; Coccidiostats; Doxycycline; Drug Interactions; Drug Therapy, Combination; Female; Half-Life; Injections, Intramuscular; Injections, Intravenous; Male; Nitriles; Piperidines; Quinazolinones; Triazines

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 Residual activity depleted gradually over several days, as shown by higher lesion scores when medication was withdrawn for up to 3 days before inoculation.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.

Topics: Amprolium; Animal Feed; Animals; Chickens; Coccidiosis; Coccidiostats; Eimeria tenella; Feces; Female; Lasalocid; Male; Monensin; Nicarbazin; Nitriles; Piperidines; Poultry Diseases; Pyrans; Quinazolines; Quinazolinones; Random Allocation; Triazines

Ten Eimeria field isolates from North Germany were studied in battery tests for sensitivity to selected anticoccidials. A high percentage of the Eimeria field isolates (9 out of 10) showed resistance to anticoccidials, mostly multiple resistance. Partial or complete resistance to maduramicin was found in 7 field isolates, to monensin in 6, to salinomycin in 5, to nicarbazin in 8, to halofuginone in 7, to robenidine and toltrazuril in 1, and to diclazuril in 2 field isolates. Multiple resistance had developed in 7 of the 10 isolates. Cross-resistance between maduramicin, monensin, and salinomycin occurred in 5 Eimeria isolates. One isolate showed cross-resistance between diclazuril and toltrazuril. From the resistant isolates 15 pure E. acerculina and 5 pure E. brunetti strains were obtained by single oocyst infections. Seven of the E. acerculina and 4 of the E. brunetti strains showed resistance or partial resistance that was also present in the original isolate. Ten of 11 resistant strains were multiply resistant.

Topics: Animals; Chickens; Coccidiosis; Coccidiostats; Drug Resistance; Drug Resistance, Multiple; Eimeria; Germany; Lactones; Male; Monensin; Nicarbazin; Nitriles; Piperidines; Poultry Diseases; Pyrans; Quinazolines; Quinazolinones; Robenidine; Triazines