用丙硫苯咪唑检测羊线虫抗药性的体外虫卵孵化试验

为探讨用丙硫苯咪唑进行体外虫卵孵化试验检测羊线虫对苯并咪唑类药物的抗药性,对23个羊场的25份田间样品用丙硫苯咪唑和噻苯咪唑进行了虫卵孵化试验并与先前减卵试验（faecal egg count re-duction test,FECRT）的结果比较。结果表明,25份样品中,丙硫苯咪唑和噻苯咪唑对受检虫卵的半数致死量（LD50）均值分别为0.050 1和0.054 0μg/mL,差异不显著。FECRT检测有抗药性的4个羊场,75%的样品对丙硫苯咪唑和噻苯咪唑的LD50均值均在0.1μg/mL以上,只有1个羊场的的LD50值分别为0.068 9μg/mL（丙硫苯咪唑）和0.071 2μg/mL（噻苯咪唑）。检测为可疑的2个羊场,其样品的LD50值为0.04～0.07μg/mL;FECRT检测敏感的蠕虫群体的LD50均在0.04μg/mL以下。此外,丙硫苯咪唑用纯的二甲基亚砜溶解和稀释后于4℃保存7 d,LD50值变化不大,提示药效无明显下降,而保存14 d后药效有下降趋势。

虫卵孵化试验对某羊场羊线虫抗药性的检测

为了解家畜寄生线虫对使用较久的驱虫药丙硫咪唑的抗药性情况， 用虫卵孵化试验对江苏某羊场进行抗药性检测， 测得丙硫咪唑虫卵孵化半数抑制量ＩＤ５０ ＝ ０－０６０ ２ μｇ／ｍＬ， 约是敏感株（０－０２０ ４ μｇ／ｍＬ） 的３ 倍， 但较世界兽医寄生虫促进协会提出的线虫抗药性临界值（０－１ μｇ／ｍＬ） 小。虫卵减少试验也证实了该羊场不存在抗药性。因此该场羊寄生线虫尚无抗药性。

黑龙江大山种羊场羊线虫抗药性的检测──粪便虫卵减少试验检查线虫抗药株

为了查明羊线虫对某种药物的抗药性，本试验用粪便虫卵减少试验（ＦＥＣＴＲＴ）对黑龙江大山种羊场羊线虫的抗药性进行了检测。结果表明该羊场的羊线虫对丙硫苯咪唑产生了抗药性；改用佳灵三特、羊佳２号进行治疗，获得较为满意的结果。粪卵减少试验是检测线虫抗药性的一种简单实用的方法。

河北省坝上地区绵羊消化道线虫对丙硫苯咪唑抗药性的检测

目的 为了查明绵羊消化道线虫对丙硫苯咪唑的抗药性。方法 应用粪便虫卵减少试验 (FECRT)对河北省坝上地区绵羊消化道线虫的抗药性进行了检测。结果 应用 5 m g/ kg丙硫苯咪唑对 5组绵羊进行驱虫的虫卵减少率分别为 4 3.9% ,38.4 6 % ,4 9.0 9% ,37.6 3%和 4 3.35 % ,驱净率分别为 2 0 % ,15 % ,15 % ,2 5 %和 10 %。结论 根据 FECRT 95 %置信域小于 90 % 。

Suspected Resistance against Moxidectin in Sheep Strongylid Nematodes in Austria

Loss of efficacy due to resistance development against anthelmintics in livestock parasites is a growing concern worldwide. The aim of the present study was to determine the efficacy of moxidectin, a frequently-used macrocyclic lactone, against gastrointestinal nematodes of sheep in Austria. Individual faecal samples were collected from 243 adult sheep from 16 flocks in Styria and Salzburg before deworming and egg excretion （EPG （eggs per gram） of faeces） was determined using a modified McMaster technique. The animals were randomly assigned to a treatment group which received 0.2 mg/kg of body weight of moxidectin （Cydectin , Zoetis Schweiz GmbH, Zurich, Switzerland）, and an untreated control group. Fourteen days after deworming a FECRT （faecal egg count reduction test） for detection of anthelmintic resistance was performed. Before deworming, the infection rate for gastrointestinal strongylids was 94.7%, with EPG values of 0-5,800. The FECRT showed reduction rates between 93.08% and 99.78% and was sufficient in 15/16 flocks. The lower confidence interval was 70.0-100%. In 3/16 flocks this value was below the minimum for sufficient efficacy （70.0%, 79.0%, 85.0%）, and in two flocks the value （90,0%） was near the limit. These results indicated a （suspected） reduced efficacy of moxidectin in 5/16 examined flocks.