用虫卵孵化试验对江苏羊场线虫抗药性的检测

用虫卵孵化试验对江苏羊场线虫抗药性进行了检测,测得其虫卵经半数抑制量ＥＤ５０为０．０６３３μｇ／ｍＬ丙硫苯咪唑,是敏感株的２０余倍。该方法操作方便,快速,结果客观,敏感,可以用于检测虫株抗药性的发生和抗药性动态变化规律分析,为寄生虫病防止抗药提供有效依据。     

虫卵孵化试验对某羊场关线虫抗药性的检测

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，用虫卵孵化对江苏某羊场进行抗药性检测，测得内硫咪唑虫卵孵化半数抑制量ＩＤ５０＝０．０６０２μｇ／ｍＬ，约是敏感株（０．０１９４μｇ／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０．１μｇ／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。     

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。     

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。     

虫卵孵化试验对山羊捻转血矛线虫左旋咪唑抗药性检测

在多次使用左旋咪唑后不能有效控制羊线虫病的羊场是否有线虫抗药性产生,我们用改良的虫卵孵化试验进行抗药性检测,在控制温度的条件下进行样品中的虫卵浓集和孵化,当虫卵发育到即将孵化时加入不同剂量的左旋咪唑让其暴露于不同药物浓度中继续孵化,适时终止孵化,并计算虫卵孵化抑制率。结果表明加入药物继续孵化6和9 h,药物浓度自然对数值与虫卵死亡机率值呈直线回归关系,ED50分别为0.295ug/mL和0.406 ug/mL,与文献报道左旋咪唑捻转血矛线虫敏感株的ED50接近,经虫卵减少试验证实该羊场未产生左旋咪唑抗药性。     

用虫卵孵化试验检查羊捻转血矛线虫的抗药性

用虫卵孵化试验对上海某羊肠的羊捻转血矛线虫的抗药性进行了检查,结果表明该羊肠有抗丙硫苯咪唑捻转血矛线虫存在,其５０％抑制虫卵有效孵化率（ＥＤ５０）为０．０８７,０．０１μｇ／ｍＬ,噻苯咪唑或０．０４８,０．０２μｇ／ｍＬ丙硫苯咪唑,而敏感株ＥＤ５０为０．００４５,０．００８５μｇ／ｍＬ噻苯咪唑或０．００６４,０．００２３μｇ／ｍＬ丙硫苯咪唑,抗药株ＥＤ５０值明量高于敏感株,改用羊佳１号进行治疗,取     

山羊线虫对丙硫咪唑抗药性的虫卵孵化抑制试验与粪便虫卵减少试验的相关性

为探讨山羊线虫对丙硫咪唑抗药性的虫卵孵化抑制试验与临床治疗试验的相关性,采用WAAVP推荐的虫卵孵化试验,测定了5个羊场的山羊线虫对丙硫咪唑抗药性的IC50值,结果依次为0.066 58、0.202 10、0.269 90、0.273 40、0.359 60 mg/L.同时,以丙硫咪唑3、5、8、11、13、17 mg/kg剂量分别对这5个山羊场进行临床驱虫试验,其CD100值分别为3、5、8、8、11 mg/kg.经检验分析,IC50值与CD100值之间的相关系数为0.977 0,即呈正直线型相关.     

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 % ,表明试验羊对该药有抗药性     

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 …

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,获得了较为满意的结果。     

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。     

盐酸阿苯达唑亚砜的合成

以阿苯达唑为原料,采用一锅合成法,通过氧化、酸化反应得到目标产物盐酸阿苯达唑亚砜。以丙酮为反应溶剂,当阿苯达唑和盐酸的投料比为30 g∶13 mL,阿苯达唑和双氧水的投料比为1∶1.01(n∶n),反应时间为30 min时,制备的盐酸阿苯达唑亚砜的收率为95.78%,通过IR、1H-NMR1、3C-NMR和ESI-MS分析对其产物结构进行了确证。     

牛肉中阿苯达唑及其代谢产物残留的检测

阿苯达唑是一种广谱抗蠕虫药,但是由于用药不当等原因,其在动物可食性组织中的残留可能刺激神经系统及消化系统、触发过敏反应甚至出现肝功能异常。本试验基于5μg/kg的检验限建立牛肉中的阿苯达唑及其代谢产物的检测方法——高效液相色谱法。样品中残留的阿苯达唑及其主要代谢产物阿苯达唑砜和阿苯达唑亚砜,经乙醚提取,乙腈和己烷萃取,由高效液相色谱（配紫外检测器）测定得到阿苯达唑及其亚砜与砜的平均回收率分别为71.8%～88.6%、78.1%～85.6%和83.1%～91.9%,变异系数分别为2.8%～9.2%、0.9%～4.9%和1.4%～4.8%。     

Albendazole repeated administration induces cytochromes P4501A and accelerates albendazole deactivation in mouflon (Ovis musimon)

Adult mouflon ewes (Ovis musimon) were treated repeatedly with therapeutic doses of albendazole (ABZ, p.o. 7.5 mg/kg of body weight/day, for five consecutive days). Animals (treated or control) were sacrificed 24 h after the fifth dose of ABZ and liver and small intestine were collected to prepare microsomes. The activities of several biotransformation enzymes were measured in both hepatic and intestinal microsomes. A significant increase in the activity and amount of cytochromes P4501A (CYP1A) was observed in both tissues of ABZ treated mouflons compared to control animals. No other biotransformation enzymes tested were affected by five ABZ doses. The in vitro biotransformation of ABZ was studied in hepatic and intestinal microsomes from ABZ treated and control mouflons. Concentrations of two main ABZ metabolites - pharmacologically active ABZ sulfoxide and pharmacologically inactive ABZ sulfone were analysed using HPLC. A significant increase in rate of formation of ABZ sulfone (which is catalysed by CYP1A) was observed in hepatic as well as in intestinal microsomes from ABZ treated animals. The enhancement of ABZ deactivation by its repeated administration may affect the anthelmintic efficacy of this drug and may contribute to the development of parasite resistance.     

丙硫（口苯）咪唑对藏系绵羊寄生虫驱虫效果试验

驱虫是畜防工作的一项中心任务 ,是畜牧业生产发展非常重要的关键环节。 1990年开始在我州全面推广驱虫这一“畜防工程” ,牲畜寄生虫的感染强度和感染率明显下降 ,对降低春乏死亡 ,提高牲畜抗病能力 ,效果十分显著。     

Effect of age and gender in the pharmacokinetics of albendazole and albendazole sulphoxide enantiomers in goats

The kinetics of albendazole metabolites and albendazole sulphoxide enantiomers were studied in 2- and 14-month-old female and male goats, after a single oral dose administration (10 mg/kg) of an albendazole formulation. Blood samples from the jugular vein were collected at 0.5, 1, 2, 4, 6, 8, 10, 12, 16, 20, 24, 30, 36, 42, 48 and 54 h post-treatment and analyzed using a high performance liquid chromatography method. In all groups the area under the plasma concentration-time curve (AUC) and peak concentration (C_max) values of (+)-ABZSO were significantly higher than those of (−)-ABZSO. The AUC and C_max values obtained for (+)-ABZSO and (−)-ABZSO in adult animals were higher compared to the results in young animals, showing significant differences except for (+)-ABZSO in female animals. In young animals, independently of gender, the C_max appeared earlier compared to adult animals. The mean residence time (MRT) values were shorter in young animals compared to adult animals for all compounds analyzed. No sex-related differences were found for any of the parameters calculated except for the (+)-ABZSO from adult animals.     

Effect of the ionophore antibiotic monensin on the ruminal biotransformation of benzimidazole anthelmintics

The benzimidazole (BZD) anthelmintics, netobimin (NTB) pro-drug and albendazole sulphoxide (ABZSO) are reduced to albendazole (ABZ) by ruminal microflora. The aim of the current work was to evaluate the influence of the ionophore monensin (MON) on the in vitro biotransformation of NTB and ABZSO by sheep ruminal fluid. Ruminal fluid, collected from Corriedale sheep, was preincubated (24 h) either without (control) or with known MON concentrations (0.5, 1.5 and 3.0 microg/mL) at 38 degrees C under a CO2 atmosphere. Afterwards, aliquots from both MON-pretreated and control ruminal fluid samples were incubated (30 and 60 min) with 2 microg/mL of either NTB or ABZSO. Incubated samples were chemically extracted and analysed by High Performance Liquid Chromatography to quantify the metabolites formed. The rate of ABZ production after 30 min of NTB incubation with control ruminal fluid was 0.023 microg/min. Conversely, the rates of ABZ formation were significantly (P<0.05) lower (0.009, 0.011 and 0.013 microg/min) when NTB was incubated with ruminal fluid pretreated with MON (at 0.5, 1.5 and 3.0 microg/mL, respectively). After both incubation periods, the reduction of ABZSO to ABZ was 22 to 70% lower when the ruminal fluid was preincubated with the different MON concentrations. The lower ABZ production observed in the presence of MON may result in a modified availability of this molecule in the gastrointestinal (GI) tract and hence, on its anthelmintic efficacy against GI nematodes.     

不同剂量阿苯达唑治疗鼠旋毛虫病效果初探

使用不同剂量阿苯达唑对人工感染旋毛虫的小白鼠进行疗效试验,观察其不同剂量的杀虫效果.结果表明：应用阿苯达唑20 mg/（kg·d）×7治疗鼠旋毛虫病有很好的治疗效果,为阿苯达唑临床应用提供科学参考.     

Pharmacological assessment of netobimin as a potential anthelmintic for use in horses: Plasma disposition, faecal excretion and efficacy

This study aimed to determine the plasma disposition and faecal excretion of netobimin (NTB) and its respective metabolites as well as the efficacy against strongyles in horses following oral administration. Netobimin (10 mg/kg) was administered orally to 8 horses. Blood and faecal samples were collected from 1 to 120 h post-treatment and analysed by high performance liquid chromatography (HPLC). Using a chiral phase-based HPLC, plasma disposition of ABZSO enantiomers produced was also determined. Faecal strongyle egg counts (EPG) were performed by a modified McMaster’s technique before and after the treatment. Neither NTB nor ABZ were present and only albendazole sulphoxide (ABZSO) and sulphone metabolites (ABZSO₂) were detected in the plasma samples. Maximum plasma concentration of ABZSO (0.53 ± 0.14 μg/ml) and ABZSO₂ (0.36 ± 0.09 μg/ml) were observed at (t_max) 10.50 and 19.50 h, respectively following administration of NTB. The area under the curve (AUC) of the two metabolites was similar to each other. Netobimin was not detected, and ABZ was predominant in faecal samples. The maximum plasma concentration (C_max) of (−)ABZSO was significantly higher than (+)ABZSO, but the area under the curves (AUCs) of the enantiomer were not significantly different each other in plasma samples. The enantiomers of ABZSO were close to racemate in the faecal samples analyzed. Netobimin reduced the EPG by 100%, 100%, 77%, 80% and 75% 2, 4, 6, 8 and 10 weeks post-treatment, respectively. The specific behaviour of the two enantiomers probably reflects different enantioselectivity of the enzymatic systems of the liver which are responsible for sulphoxidation and sulphonation of ABZ. Considering the pharmacokinetic and efficacy parameters NTB could be used as an anthelmintic in horses.     

河北省坝上高原地区绵羊消化道线虫优势虫种季节动态研究

河北省坝上高原地区完全放牧条件下的绵羊消化道线虫优势虫种(捻转血矛线虫、羊仰口线虫和食道口线虫)季节动态：幼虫的感染强度在温暖的4～9月最低，而寒冷的10～3月较高；成虫的感染强度在6～9(或8)月最低。血矛线虫4～6月和9月～次年1月感染强度较高，羊仰口线虫除6～8月外其余各月份感染强度较高。食道口线虫4～6月为感染强度的高峰期。