Dyary Hiewa Othman, Banaz Hamasalih Qadir
Department of Basic Sciences, College of Veterinary Medicine, University of Sulaimani, Sulaymaniyah 46001, Iraq.
Directorate of Veterinary Services in Sulaymaniyah, Sulaymaniyah 46001, Iraq.
J Vet Res. 2021 Aug 19;65(3):293-299. doi: 10.2478/jvetres-2021-0047. eCollection 2021 Sep.
The control of gastrointestinal nematodes (GINs) in small ruminants is principally dependent on anthelmintic therapy, which encounters the rising problem of anthelmintic resistance (AR) development. Veterinarians reported anthelmintic failure in several sheep farms in Arbat District, Sulaymaniyah, northern Iraq, which called for a systematic study about the efficacy of three commonly used drugs: albendazole, ivermectin, and levamisole.
A faecal egg count reduction test (FECRT) was conducted to elucidate the anthelmintics' efficacies, with coprocultures to determine the GINs parasitising sheep in the study area. Larval development assays (LDAs) were conducted to determine the drugs' median inhibitory concentrations (IC).
The FECRT revealed that AR was widespread to all three drugs, and ivermectin was the least effective, reducing the faecal egg counts (FECs) by 50.5% to 57.1%. The coprocultures revealed that the GIN genera of sheep in Arbat District were , , and , and the resistance was mainly due to species. The mean IC of albendazole, ivermectin, and levamisole were 0.073 ng/mL, 7.97 ng/mL, and 1.43 ng/mL, respectively.
This study is the first Iraqi report of AR confirmed by both FECRT and LDA methods.
小反刍动物胃肠道线虫（GINs）的控制主要依赖于驱虫治疗，而驱虫治疗正面临着驱虫抗性（AR）不断增加的问题。兽医报告称，伊拉克北部苏莱曼尼亚省阿尔巴特区的几个养羊场出现驱虫失败的情况，这就需要对三种常用药物——阿苯达唑、伊维菌素和左旋咪唑的疗效进行系统研究。
进行粪便虫卵计数减少试验（FECRT）以阐明驱虫药的疗效，并进行粪便培养以确定研究区域内寄生于绵羊的胃肠道线虫种类。进行幼虫发育试验（LDA）以确定药物的半数抑制浓度（IC）。
FECRT显示，AR在这三种药物中普遍存在，伊维菌素效果最差，粪便虫卵计数（FECs）减少了50.5%至57.1%。粪便培养显示，阿尔巴特区绵羊的胃肠道线虫属为 、 和 ，抗性主要归因于 物种。阿苯达唑、伊维菌素和左旋咪唑的平均IC分别为0.073 ng/mL、7.97 ng/mL和1.43 ng/mL。
本研究是伊拉克第一份通过FECRT和LDA方法确认AR的报告。
