吡喹酮氯仿油制剂治疗山羊日本血吸虫病研究

通过口服吡喹酮氯仿油制剂（25mg/kg）治疗人工感染山羊日本血吸虫病，39天后解剖冲法，计数残存虫体，与对照组相比，减虫率为95.7%，减雌率为96.7%。早期文献报道（1981)，当口服吡喹酮剂量20mg/kg时，可获得99.8%的减虫率和100%的减雌率。鉴于国外已有吡喹酮不能完全治愈病人的报道和血吸虫可能已有抗吡喹酮的抗药性，吡喹酮治疗动物血吸虫的适宜治疗剂量值得商讨。     

吡喹酮非水溶液注射剂的研制--日本血吸虫病治疗试验

利用本课题组研制的吡喹酮非水溶液注射剂，分别进行了小鼠和牛的日本血吸虫病治疗试验。结果表明，感染日本血吸虫的小鼠按每千克体质量20mg和30mg的剂量肌肉注射吡喹酮的减雌率均达100％，人工感染日本血吸虫的牛按每千克体质量10mg和12mg的剂量肌肉注射吡喹酮的减雌率均达100％，每千克体质量8mg的剂量的减雌率为96．41％。自然感染血吸虫病牛按每千克体质量10mg的剂量肌肉注射后30d，粪便转阴率达90．50％。这一结果说明，研制的吡喹酮注射剂具有良好的治疗效果。     

吡喹酮脂质体对实验动物感染血吸虫病的疗效试验

采用逆相蒸发法(REV)制备吡喹酮脂质体,包封率为59％～62％。小白鼠腹腔注射的半数致死量(LD50)为1865mg/kg。取小白鼠150只,感染血吸虫尾蚴(40士2)条/只;家免80只,接种尾蚴(200士20)条/只。一月后,由静注给药,经32d后剖杀动物,门静脉冲洗虫子计数。结果用吡喹酮脂质体5mg/kg组小白鼠总减雌率为91.27％,减虫率为85.00％;家兔的总减雌率为97.45％,减虫率为84.92％。用10mg/kg组小白鼠的总减雌率为99.40％,减虫率为93.30％;家兔的总减雌率为99.17％,减虫率为97.65％。对照组(PZQ50mg/kg)小白鼠的总减雌率为85.91％,减虫率为82.83％;家兔的总减雌率为93.37％,减虫率为87.30％。经统计检验,小白鼠用5mg/kg组与对照组比较,减雌率和减虫率差异不显著(P＞0.05);10mg/kg组与对照组比较,减雌率和减虫率差异显著(P＜0.05)。     

吡喹酮肌肉注射液治疗山羊实验感染日本血吸虫病研究

本研究以二种吡喹酮肌肉注射液治疗山羊人工感染血吸虫病，剂量３０ｍｇ／ｋｇ，减虫率分别为９７．９％和９８．６％，减雌率分别为９７．９％１００％；剂量２０ｍｇ／ｋｇ，减虫率分别为９６．３％和９８．１％，减雌率分别为９６．９％和９８．４％，显示了良好的疗效。二种吡喹酮肌肉注射液药剂稳定性好，放置二年，未见有毒性反应，建议可在现场试用。     

口服抗原疫苗预防小鼠日本血吸虫病的初步试验

为了观察口服可溶性血吸虫成虫抗原疫苗预防小鼠日本血吸虫病的效果，本试验应用生物可降解的天然高分子材料──壳聚糖作为载体[1，2]，运用单凝聚法[4]制成粒径500～1500μm的可溶性血吸虫成虫抗原微囊，胃饲ICR小鼠，经3次免疫后人工感染日本血吸虫，4周后剖杀小鼠。结果，试验组获得43．23％（P＜0．05）减虫率和41．18％（P＞0．05）减雌率。血吸虫抗原微囊体外释放试验表明，在0．01MolpH7．2PBS中微囊4h后即开始释放抗原，至第7天时抗原释放结束，累积释放抗原95．87％。     

吡喹酮注射剂早期治疗小鼠血吸虫病效果的初步研究

为探索吡喹酮新制剂早期治疗血吸虫病效果,对人工感染日本血吸虫20d的小鼠皮下给药进行减虫率、肝脏减卵率统计,并在不同时间点对口服组和皮下注射吡喹酮新制剂组的未感染小鼠在给药后采集血浆,高效液相色谱法建立药时曲线。结果显示新制剂600mg/kg剂量治疗的3次试验的减虫率分别为72.88%、82.69%和56.7%,肝脏减卵率分别为81.7%、94.8%和70.7%,对感染20d期别的血吸虫有较好效果。而高效液相色谱法检测血药浓度显示,新制剂经皮下给药方式可使有效杀虫浓度(约0.3μg/mL)持续10d以上,具有缓释作用。吡喹酮新注射制剂能杀灭20d童虫,减少血吸虫病的危害,对血吸虫病的防治有较大的意义。     

IgG1型单克隆抗体和吡喹酮协同预防日本血吸虫病的研究

6组昆明系小鼠人工感染日本血吸虫尾蚴前2小时,组1和组2胃饲低剂量吡喹酮(20mg/kg),并分别腹腔注入鼠抗日本血吸虫IgG_1型单克隆抗体ISj51和ISj55作被动免疫,4天后重复1次,4周后剖杀集虫。结果表明,单抗合并吡喹酮的组1和组2的减雌率分别为45.32％和42.95％,均明显高于(p<0.01)仅作腹腔被动免疫转移ISj 51和ISj 55单抗的组3和组4(分别为15.11％和19.44％),亦高于(p>0.05)仅用单剂吡喹酮的组5(37.41％)。2株单抗在巨噬细胞和嗜酸性粒细胞的介导下,杀伤童虫率接近1:2稀释的8周阳性鼠血清(分别为37.50％,46.88％和48.00％,41.18％)。提示:鼠抗日本血吸虫IgG_1型单抗协同低剂量吡喹酮,具有预防日本血吸虫感染,提高灭雌率,降低吡喹酮毒副作用的优点,对控制和预防日本血吸虫病的传播具有一定的意义。     

犬应用吡喹酮缓释剂后血药浓度的检测

应用反相高效液相色谱法测定犬用吡喹酮缓释剂后的血药浓度。犬应用包埋缓释剂后1～7个月血药浓度为0．48～1．45μg／ml；犬应用注射缓释剂后1～6个月血药浓度为0．051～0．2μg／ml；犬口服常用驱（杀）虫剂量后1～8小时的血药浓度为0．66～1．60μg／ml。显然前者与口服浓度相当，而后者则远远低于口服浓度；前者预防效果减虫率达98．46～100％，后者仅达55．65～65．11％；从而以确凿的数据证实犬用包埋型缓释剂的有效预防期至少在7个月以上。     

二丁酰环腺苷酸(dbcAMP)对猪生长及糖代谢的调控

通过皮下注射和饲料添加不同剂量二丁酰环腺苷酸（dbcAMP)进行饲养试验，研究其对猪生长和糖代谢调控的效果。结果表明：皮下注射1.0mg/kg和饲料添加20mg/kg为最佳调控剂量，在生长猪阶段，日增重分别提高13．61％和15．41％（P＜0．05）；料重比分别降低18．81％和19．10％（P＜0．01）；在肥育猪阶段日增重和料重比差异不显著（P＞0．05）。肥育猪肝糖原含量分别降低27．32％和27．18％（P＜0．05）；肌糖原含量分别降低28．79％和31．79％（P＜0．05）。血糖含量在生长猪和肥育猪阶段都明显提高（P＜0．05）。证明dbcAMP对猪的生长性能和糖代谢有明显调控作用。     

复合酶对生长猪效果试验

选择120头本地饲养的哈白猪随机分为4组,每组设2个重复。4组分别饲喂养0mg/kg、10mg/kg、100mg/kg、1000mg/kg的商品用复合酶制剂。试验结果表明,猪日粮中添加酶制剂,可促进生长和改善饲料利用率。与对照组相比,添加10mg/kg酶制剂组平均日增重提高7．69％（P＜0．05）,饲养利用率提高,4．70％（P＜0．05）,经济效益提高50．76（P＜0．01）;添加100mg/kg酶制剂组平均日增重提高7．69(P<0.05),饲养利用率提高8．39％（P＜0．01）,经济效益提高79．72％（P＜0．01）;添加1000mg/kg酶制剂组平均日增重提高3．08％（P＞0．05）,饲料利用率提高5．70％（P＜0．05）,经济效益提高－10．90％（P＞0．05）。     

复方吡喹酮注射液防治羊脑多头蚴病的试验研究

为了获得复方吡喹酮注射液治疗羊脑多头蚴病的最佳治疗剂量,本试验应用复方吡喹酮注射液30、50、80 mg/kg BW三个剂量组对患羊脑多头蚴病的绵羊进行治疗,设80 mg/kg BW剂量的丙硫咪唑作为药物对照组.试验结果表明,30 mg/kg BW剂量组治愈率较低,为68.97%,不能达到治疗目的;50和80 mg/kg BW剂量对羊脑多头蚴均有很强的驱杀作用,对病羊的治愈率分别为91.84%和92.85%,但两组间差异不显著(P＞0.05);高、中剂量组(80、50 mg/kg BW)与低剂量组、药物对照组比较差异极显著(P＜0.01).50 mg/kg BW剂量为防治羊脑多头蚴病的最佳治疗剂量.     

约氏乳杆菌对大鼠生长性能、血液指标及脏器指数的影响

本试验旨在研究约氏乳杆菌对大鼠生长性能、血液指标及脏器指数的影响。试验选取SD大鼠80只,雌雄各半。大鼠按照体重相近的原则随机分为4个剂量组,即阴性对照组、试验Ⅰ(5 000 mg/kg体重)、试验Ⅱ(1 000 mg/kg体重)和试验Ⅲ组(200 mg/kg体重)。试验期为30 d。结果表明:试验剂量为200~1 000 mg/kg体重时,约氏乳杆菌对大鼠体增重、总采食量、饲料转化率、血液学指标和病理学指标的影响无显著性差异(P>0.05);试验剂量为5 000 mg/kg体重时,谷草转氨酶、血糖、总胆固醇差异不显著(P>0.05);与其他剂量组相比,大鼠的体增重和总采食量显著降低(P<0.05),但饲料转化率无显著差异(P>0.05);谷丙转氨酶水平显著降低(P<0.05),白蛋白和总蛋白显著增高(P<0.05);雌性大鼠尿素氮和雄性大鼠肌酐显著增高(P<0.05)。综合分析,约氏乳杆菌剂量低于1 000 mg/kg体重时,对大鼠平均日增重、血液指标及脏器指数无影响;约氏乳杆菌剂量高于5 000 mg/kg体重时,对大鼠脏器指数有影响。     

两种药物对高原型牦牛多头蚴病的治疗效果观察

[目的]观察吡喹酮片剂、阿苯达唑干混悬剂对高原型牦牛多头蚴病的治疗效果,确定最佳剂量和用药次数。[方法]应用吡喹酮片剂按35、70 mg/kg剂量口服、阿苯达唑干混悬剂按25、50 mg/kg剂量口服治疗牦牛多头蚴病。[结果]吡喹酮片剂两个剂量的治愈率分别为72.73%和91.67%;阿苯达唑干混悬剂两个剂量的治愈率分别为81.82%和83.33%。从吡喹酮片剂35 mg/kg的剂量组死亡的2头牛检出多头蚴8个,平均感染强度2.67个;从阿苯达唑干混悬剂25 mg/kg的剂量组死亡的1头牛检出脑多头蚴2.0个,平均感染强度2个。从阳性对照组死亡的10头牛检出脑多头蚴37个,平均感染强度3.7个。[结论]吡喹酮片剂70mg/kg剂量间隔5 d三次给药达高效,适于推广应用。     

Use of praziquantel for the control of Moniezia expansa in lambs

The efficacy of a drench containing praziquantel in combination with levamisole was evaluated in four trials performed in the 1990-91 and 1992-93 seasons in the Waikato Region of New Zealand. The trials involved 93 naturally infected lambs and compared the efficacy of a 3.75 mg/kg praziquantel 7.5mg/kg levamisole drench against Moniezia expansa, with albendazole, an albendazole-levamisole combination and oxyclozanide-levamisole combination in controlled trials. There was no significant reduction in the number of Moniezia expansa scoleces or proglottids in the control, albendazole and albendazole-levamisole groups. Oxyclozanide gave a high clearance of proglottids, but a 28% reduction of scoleces. The praziquantel-levamisole combination demonstrated complete removal of segments in all trials, and of scoleces in two trials. One scolex was found in each of the two other trials. The combination was also tested for efficacy against nematode parasites. Total worm counts indicated that levamisole in the praziquantel-levamisole combination drench retained its efficacy. The economic benefits of the use of the praziquantel-levamisole drench were investigated. This trial compared the liveweight gains of three groups of 100 lambs treated twice 4 weeks apart with either levamisole or with the praziquantel-levamisole combination or acting as untreated control group. The group treated with the praziquantel-levamisole combination gained significantly more weight in both 4-week periods and overall, when compared with either the control or levamisole treated animals.     

Anthelmintic efficacy of febantel combined with praziquantel against Ancylostoma tubaeforme, Toxocara cati, and Taenia taeniaeformis in cats

Forty cats, each harboring 2 or 3 parasitic infections (Ancylostoma tubaeforme, Toxocara cati, and/or Taenia taeniaeformis), were used to titrate the anthelmintic efficacy of a paste containing 3.4% febantel and 0.34% praziquantel. The cats were allotted into 4 groups (10 cats/group). For 3 consecutive days, the cats were given febantel/praziquantel at 5/0.5 mg/kg/day, 10/1 mg/kg/day, 15/1.5 mg/kg/day, or a blank paste vehicle (control) at 0.29 g/kg of body weight. The recommended dosage of 10 mg of febantel and 1 mg of praziquantel/kg cleared greater than or equal to 98% of the 3 helminth species.     

Anthelmintic treatment in horses: the extra-label use of products and the danger of under-dosing

Anthelmintic products form the basis of helminth control practices on horse stud farms at present. Regular evaluation of the efficacy of these products is advisable, as it will provide information on the worm egg reappearance period and the resistance status in the worm population. The aim of this study was to evaluate the efficacy of doramectin, pyrantel pamoate, ivermectin and moxidectin on a Thoroughbred stud farm in the Western Cape Province, South Africa. The study also compared the anthelmintic efficacy of two moxidectin formulations administered at their recommended dosages (an injectable, at 0.2 mg/kg, not registered for horses, and an oral gel at 0.4 mg/kg, registered for horses). Two mixed-sex groups of 30 yearlings and 40 weaners were tested in 2001 and 2002, respectively, divided into 3 and 4 groups of equal size. In 2001, moxidectin was one of 3 drugs administered orally and at a dose rate of 0.4 mg/kg. In 2002, pyrantel pamoate and ivermectin were orally administered at 19 and 0.2 mg/kg. Moxidectin and doramectin (the latter not registered for horses) were administered by intramuscular injection at a dose of 0.2 mg/kg, the dosage registered for other host species. The faecal egg count reduction test was used to determine the anthelmintic efficacies in both years. Each animal acted as its own control and the arithmetic mean faecal egg count and lower 95% confidence limit was calculated for each of the groups. A 100% reduction in the faecal egg counts and a 100% lower 95% confidence limit was recorded for moxidectin (0.4 mg/kg) in 2001. In 2002, a 99% and 96% reduction was recorded for pyrantel pamoate and ivermectin, respectively. In the same year doramectin and moxidectin (both injectable and given at 0.2 mg/kg) did not have any effect on worm egg counts. Of the 4 drugs tested in 2002, only pyrantel pamoate recorded lower 95% confidence limits above 90%.