robenidine and halofuginone

Topics: Animals; Chickens; Chromatography, Liquid; Coccidiosis; Eggs; Food Analysis; Humans; Lactones; Lasalocid; Liquid-Liquid Extraction; Monensin; Nigericin; Piperidines; Poultry; Pyrans; Quinazolinones; Robenidine; Tandem Mass Spectrometry; United States; United States Food and Drug Administration

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

A floor-pen trial was conducted to investigate the effects of different shuttle programs upon the growth of broilers to 8 wk of age. Nicarbazin, halofuginone, and robenidine, when included in the starter feed for 3 wk, were effective in preventing lesions due to Eimeria. The effects of medication upon performance were apparent, medicated groups gaining more weight by 6 wk and having a lower feed conversion at 6, 7, and 8 wk than the unmedicated controls. There were no significant differences in body weight at 6, 7, or 8 wk or feed conversion at 6 or 7 wk among the medicated groups, whether medication was withdrawn for 7 or 14 days. A decrease in the number of small and medium oocysts in the litter was observed as the trial progressed. Few large oocysts (Eimeria maxima) were seen in the medicated groups. Numbers of oocysts did not increase following withdrawal of medication. Birds from all medicated groups were challenged at 6 wk with oocysts of Eimeria acervulina, Eimeria maxima, or Eimeria tenella. Weight gains were similar to that of the unchallenged controls, indicating that they had acquired immunity to these species of Eimeria.

Topics: Animals; Body Weight; Chickens; Coccidiosis; Coccidiostats; Diet; Eimeria; Feces; Immunity; Male; Nicarbazin; Parasite Egg Count; Piperidines; Poultry Diseases; Quinazolines; Quinazolinones; Robenidine

A line of Eimeria tenella (H) resistant to robenidine, decoquinate and amprolium has been produced by genetic recombination. It was not possible to obtain a cross between this line and lines resistant to clopidol or arprinocid and halofuginone. Recombination between lines resistant to arprinocid and halofuginone resulted in a loss of pathogenicity.

Topics: Adenine; Amprolium; Animals; Chickens; Clopidol; Coccidiostats; Decoquinate; Drug Resistance, Microbial; Eimeria; Guanidines; Hydroxyquinolines; Picolines; Piperidines; Quinazolines; Quinazolinones; Recombination, Genetic; Robenidine

Coccidia were isolated from litter samples collected in poultry houses in Georgia and other southeastern states and from intestinal scrapings from chickens submitted to diagnostic laboratories. The most common species of coccidia encountered were E. tenella, E. acervulina, and E. maxima. Each of the 41 isolates was tested for sensitivity to eight commercial anticoccidial drugs. Most of the isolates were resistant to some of the drugs judged by the parameters of percent weight gain, percent lesion score reduction, and a sensitivity index score. There was a high frequency of resistance to clopidol, amprolium/ethopabate, nequinate, zoalene, and sulfaquinoxaline. A very small percentage of the isolates tested were resistant to nicarbazin, robenidine, or halofuginone.

Topics: Amprolium; Animals; Chickens; Coccidiostats; Drug Resistance; Eimeria; Intestines; Manure; Nicarbazin; Piperidines; Quinazolines; Quinazolinones; Robenidine