柔嫩艾美耳球虫对盐酸氟乙基硫胺素耐药性的诱导

Development of Eimeria tenella Resistance to Fluoroethyl Thiamine Hydrochloride

关键词:  艾美耳球虫  氨丙啉  盐酸氟乙基硫胺素  耐药性  鸡

Key words:  Eimeria tenella  amprolium  fluoroethyl thiamine hydrochloride  drug-resistance  chicken

摘要:

为评估盐酸氟乙基硫胺素产生抗药性的倾向，采用药物浓度递增法，在实验条件下进行柔嫩艾美耳球虫耐药性的诱导研究。每组动物用10只快大黄肉鸡，每只鸡接种1×105个孢子化卵囊，以50 mg/kg盐酸氨丙啉和盐酸氟乙基硫胺素为起始诱导浓度连续传代，以病变记分、存活率和卵囊数三项指标综合判定耐药性。经过10次传代，盐酸氨丙啉对敏感虫株的ACI为192.6，而对耐药虫株的ACI为109.1；经过12次传代，盐酸氟乙基硫胺素对敏感虫株的ACI为197.5，而对耐药虫株的ACI为110.6，对盐酸氨丙啉耐药虫株的ACI为163.2；结果表明成功地诱导出对盐酸氨丙啉、盐酸氟乙基硫胺素完全耐药的虫株。盐酸氟乙基硫胺素产生耐药速度慢于盐酸氨丙啉，与盐酸氨丙啉有部分交叉耐药性。

Abstract:

The resistance of Eimeria tenella against the anticoccidial drug fluoroethyl thiamine hydrochloride and amprolium was induced experimentally for evaluate the resistant tendency of fluoroethyl thiamine hydrochloride. The initial concentration of fluoroethyl thiamine hydrochloride and amprolium hydrochloride was 50 mg/kg, E. tenella was serially passaged in chickens with gradually increasing concentration of fluoroethyl thiamine hydrochloride, The drug resistance was assessed by lesion scores, survival rate and number of oocysts, it took 10 and 12 passages to produce the drug resistant strain of E. tenella to 800 mg/kg hydrochloride amprolium and 800 mg/kg fluoroethyl thiamine hydrochloride, respectively. The effects of the drugs were assessed by ACl (anticoccidial index), the results show that the resistance of fluoroethyl thiamine hydrochloride was slower to be developed than amprolium hydrochloride, and was effective to the amprolium-resistant strain.