柔嫩艾美耳球虫扬州分离株对8种抗球虫药的抗药性

将柔嫩艾美耳球虫(Eimeria tenella)扬州分离株感染14日龄苏禽黄羽肉鸡,设立8个用药组、1个感染不用药对照组和1个不感染不用药对照组,以相对卵囊产量、病变记分减少率、最适抗球虫百分数和抗球虫指数为指标对该虫株对盐霉素、马杜拉霉素、球痢灵、氯羟吡啶、氨丙啉、尼卡巴嗪、甲基三嗪酮、地克珠利等8种常用抗球虫药的抗药性进行了综合评定,分析了该地区球虫的抗药性及对策。结果表明,该虫株对甲基三嗪酮敏感,对氨丙啉具有中度抗药性,对盐霉素、马杜拉霉素、球痢灵、氯羟吡啶、尼卡巴嗪、地克珠利等其他6种药物具有完全抗药性。提示目前在扬州地区甲基三嗪酮抗球虫疗效最好,氨丙琳效果稍差,应合理使用,盐霉素等其他6种药物应慎用、减少或暂停使用。

Resistance of Eimeria tenella isolated from Yangzhou to eight commonly used anticoccidial drugs

One Eimeria tenella field isolate from Yangzhou was studied in a battery test for evaluating resistances to eight commonly used anticoccidial drugs. Suqin yellow chickens were randomly divided into 10 groups of 20 each, which consisted of 8 medicated groups, one uninfected and unmedicated control, and one unmedicated and infected control. Chickens of medicated groups and infected control were infected with 105 sporulated oocysts each at the age of 2 weeks and prophylactic medication commenced 2 days prior to infection. Drug resistances were assessed by calculating the relative oocyst production (ROP), reduction of lesion scores (RLS), percentage optimum anticoccidial activity (POAA) and anticoccidial index (ACI). Results revealed that the E.tenella isolate from Yangzhou was sensitive to toltrazuril, middle resistant to amprolium, complete resistant to other six drugs. It suggested that toltrazuril can be used in Yangzhou district, amprolium should be used reasonably, and the other six drugs should not be used at present.