van Wyk J A, van Schalkwyk P C, Gerger H M, Visser E L, Alves R M, van Schalkwyk L
Veterinary Research Institute, Onderstepoort, Republic of South Africa.
Onderstepoort J Vet Res. 1989 Dec;56(4):257-62.
A strain of Haemonchus contortus from the Pietermaritzburg district of Natal was found to be resistant to levamisole (geometric mean efficacy 76.5%), morantel (41.9%), the benzimidazoles (oxfendazole: 33.7%) and rafoxanide (82.0%), but apparently fully susceptible to closantel and disophenol. In the case of ivermectin, a mean of 5.2% of the H. contortus was not removed at a dosage of 200 micrograms kg-1 live mass. A second strain of H. contortus, from Amsterdam in the south-eastern Transvaal, showed reduced susceptibility to levamisole (80.8%) and morantel (46.2%), the only 2 drugs tested. This is apparently the first report of resistance to the levamisole/morantel group of anthelmintics in sheep in South Africa.
在纳塔尔省彼得马里茨堡地区发现的一种捻转血矛线虫对左旋咪唑（几何平均效力76.5%）、噻嘧啶（41.9%）、苯并咪唑类（奥芬达唑：33.7%）和硝碘酚腈（82.0%）具有抗性，但显然对氯氰碘柳胺和双酚完全敏感。就伊维菌素而言，以200微克/千克活体重的剂量给药时，平均有5.2%的捻转血矛线虫未被清除。来自德兰士瓦省东南部阿姆斯特丹的第二种捻转血矛线虫菌株对左旋咪唑（80.8%）和噻嘧啶（46.2%）的敏感性降低，这是仅测试的两种药物。这显然是南非绵羊对左旋咪唑/噻嘧啶类驱虫药产生抗性的首次报告。
