伊维菌素吡喹酮咀嚼片含量测定方法的建立

为了建立伊维菌素吡喹酮咀嚼片同时测定两种主药含量的方法,采用十八烷基硅烷键合硅胶为填充剂,以乙腈∶水的梯度洗脱系统作为流动相,伊维菌素检测波长为245 nm,吡喹酮检测波长为210 nm。在该色谱条件下,溶剂和辅料对伊维菌素和吡喹酮出峰均无干扰,伊维菌素和吡喹酮与相邻杂质峰分离良好。伊维菌素在2～400μg/m L的浓度范围线性关系良好;吡喹酮在1～100μg/m L的浓度范围内线性关系良好。伊维菌素回收率为102.5%,吡喹酮回收率为99.4%。该方法操作简便,准确度高,重复性好,可用于伊维菌素吡喹酮咀嚼片同时测定两种主药的含量。     

高效液相色谱法测定赛鸽用复方吡喹酮胶囊中吡喹酮和伊维菌素的含量

用高效液相色谱法同时测定赛鸽用复方吡喹酮胶囊中吡喹酮和伊维菌素的含量.采用Nova-Pak C18柱(150 mm×3.9 mm,4 μm),以乙腈-甲醇-水(53:35:12)为流动相,流速为1.0 mL/min,检测波长254 nm,柱温25℃.在此色谱条件下,吡喹酮和伊维菌素的分离良好,吡喹酮和伊维菌素分别在511～1 534μg/mL和10.1～30.6μg/mL浓度范围内峰面积与浓度呈良好的线性关系(r＞0.999).按外标法以峰面积计算进行测定,吡喹酮和伊维菌素的平均回收率分别为99.9%和98.3%,RSD分别为0.3%和0.6%(n=9).本方法简便、快速、准确,适用于赛鸽用复方吡喹酮胶囊中吡喹酮和伊维菌素含量的测定.     

RP-HPLC检测复方注射剂中伊维菌素和吡喹酮的含量

为了用高效液相色谱法同时测定复方注射剂中伊维菌素和吡喹酮的含量。采用Hyper-C lone 5u C18柱（250 mm×4.60 mm,5μm）,以乙腈-甲醇-水（53∶35∶12）为流动相,流速为1.0mL/m in,检测波长254 nm,柱温30℃的液相检测方法。结果表明,在此色谱条件下,吡喹酮和伊维菌素的分离良好,吡喹酮和伊维菌素分别在30~500μg/mL和5~40μg/mL浓度范围内峰面积与浓度呈良好的线性关系（r2〉0.99）。按外标法以峰面积计算进行测定,吡喹酮和伊维菌素的平均回收率分别为98.93%和95.89%,RSD分别为0.33%和1.58%（n=9）。说明该方法简便、快速、准确,适用于复方吡喹酮注射液中吡喹酮和伊维菌素含量的测定。     

羊体内寄生虫的驱虫试验

为进一步做好寄生虫病防控工作,保证驱虫药品的生物安全,确保驱虫药品防治效果。本试验采用口服伊维菌素溶液、阿苯达唑混悬液、吡喹酮片、伊维菌素-阿苯达唑混悬液和伊维菌素-吡喹酮纳米乳等5种驱虫药的方式,对羊体内寄生虫进行了驱虫试验。结果表明:5种药物的虫卵减少率达83%以上,且伊维菌素-阿苯达唑混悬液和伊维菌素-吡喹酮纳米乳虫卵减少率分别为96.07%和95.56%,对照组前后两次粪检虫卵数无明显变化。说明5种药物均具有良好的驱虫效果,且复方制剂驱虫效果优于单方制剂驱虫效果,羊体重增重效果更佳。复方制剂具有疗效更佳、安全性高、价格低廉、驱虫谱更广等特点,具有更好的经济效益。     

维他昔布咀嚼片体外溶出度的测定

为了建立了维他昔布咀嚼片体外溶出度的测定方法,以0.8％十二烷基硫酸钠溶液为溶出介质,采用桨法(50 r/min),用紫外-可见分光光度法测定溶出度.结果显示,维他昔布浓度在0.002496 ～0.017472 mg/mL范围内,与吸收度呈良好的线性关系(r=0.9995),加样回收率为102.9％(RSD为1.36％),三批样品30 min时溶出度在80％以上.建立的溶出度测定方法重现性,均一性良好,样品溶出度大于80％,可用于维他昔布咀嚼片中溶出度的测定.     

几种驱虫药物对山羊寄生虫效果的比较

对伊维菌素、丙硫咪唑、吡喹酮3种药物的驱虫效果进行了对比试验。结果表明,丙硫咪唑相比其他两种药物而言更广谱、高效低毒、成本低廉,但由于其对螨虫无效,实际工作中需使用伊维菌素进行二次驱虫。     

欣虫净复方注射剂对羊体内寄生虫驱除试验

伊维菌素和吡喹酮是目前优良的抗动物寄生虫病药物,伊维菌素是近20年来同时防治动物各种线虫病、体外寄生虫病效果最好的药物之一,而吡喹酮在防治动物的绦虫病(包括绦虫蚴病),吸虫病(尤其是血吸虫)方面具有其他抗寄生虫药物无法比拟的优点,这两种药物如果组成复方制剂在驱虫谱上可以对几乎所有的动物寄生虫产生驱杀作用,但由于吡喹酮在多种溶媒中的溶解度较低,导致注射剂量过大,容易引起注射部位吸收缓慢,炎症不易消除.本试验应用自制的以高浓度吡喹酮(20%)与适量伊维菌素组合的复方注射剂"欣虫净",通过临床试验观察了该制剂的驱虫效果.     

药物对猪囊尾蚴体外作用的比较研究

选用芬苯达唑、奥芬达唑、氟苯达唑和伊维菌素体外作用猪囊尾蚴,并与吡喹酮和阿苯达唑比较。于用药后６,１２,２４,３６ｈ进行光镜观察。结果表明：芬苯达唑,奥芬达唑和氟苯达只均能体外杀灭猪囊尾蚴,强烈程度顺序为吡喹酮、芬苯达只,阿苯达唑,奥芬达唑,氟苯达唑,发挥作用的时间顺序为吡喹酮,奥芬达唑,芬苯达唑,阿苯达唑,氟苯达唑。伊维菌素无杀灭猪囊尾病作用。     

复方氨基葡萄糖片溶出度测定方法的建立

目的 :采用有效的措施制定出复方氨基葡糖糖片的溶出度测定方法。方法 :本文主要采用的是高效液相色谱法以及紫外分光光度法测定复方氨基葡萄糖片溶出度。测定人员还利用浆法,将累积溶出度作为指标筛选介质以及转速,为了保证测定结果的准确性,相关人员还创造了良好的测定条件。结果:本文所建立的溶出度测定方法收到了较好的效果,而且操作较为简单,测定结果准确度高,值得在复方氨基葡萄糖片溶出度测定中广泛推广。     

高效液相色谱法测定德拉昔布咀嚼片的体外溶出度

建立了德拉昔布咀嚼片溶出度测定的高效液相色谱法,并对德拉昔布咀嚼片和Deramaxx咀嚼片的溶出度进行比较。方法为浆法,转速为50 r/min,0.8%十二烷基硫酸钠为溶出介质,于5、10、15、20、30、40、50 min分别采样;采用Waters XSelect H88 C18(4.6 mm×250 mm,5μm)色谱柱,磷酸盐缓冲液(pH4.5)-乙腈(52∶48,V/V)为流动相,检测波长252 nm;柱温30℃;外标法定量。结果表明,德拉昔布在5~25μg/mL浓度范围内线性良好(r²=0.9992),检测限与定量限分别为0.81μg/mL、2.57μg/mL;平均回收率为101.8%±0.91%;德拉昔布咀嚼片与Deramaxx溶出度在30 min内分别为87.78%±1.91%和88.76%±2.05%,符合规定。试验所建立的方法简便、准确、专属性强,可用于德拉昔布咀嚼片的溶出度测定。     

Efficacy of ivermectin chewable tablets and two new ivermectin tablet formulations against Dirofilaria immitis larvae in dogs.

One hundred four heartworm-free Beagles less than 1 year old were studied to determine the efficacy of ivermectin chewable tablets and of 2 other ivermectin tablet formulations against heartworm larvae. At 30 days after SC inoculation of dogs with infective Dirofilaria immitis larvae, all ivermectin formulations were given orally at dosage of 6 micrograms/kg of body weight. The ivermectin chewable tablets also were given orally at dosage of 2 and 6 micrograms/kg at 30 and 45 days, respectively, after injection of larvae. Replicates of 6 or 8 dogs in each study were formed on the basis of gender and body weight and, within replicates, were randomly allocated to treatment groups. At 30 days after injection of larvae, the additional dogs (in replicates of 8) were assigned to the control group and to the group given ivermectin chewable tablets at dosage of 6 micrograms/kg. All dogs were housed individually. Necropsy was performed approximately 5 or 6 months after larvae were administered. In both trials, all control dogs had heartworms at necropsy (University of Illinois--geometric mean, 35.0; Florida--geometric mean, 26.1). In both trials, the ivermectin chewable tablet (6 micrograms/kg) and both tablet formulations (6 micrograms/kg) given at 30 days after larval injection, and the chewable formulation (6 micrograms/kg) given at 45 days after larval injection were 100% effective (P less than 0.01) in preventing development of induced infection with D immitis.(ABSTRACT TRUNCATED AT 250 WORDS)     

Field efficacy of ivermectin plus praziquantel oral paste against naturally acquired gastrointestinal nematodes and cestodes of horses in North America and Europe

The efficacy of an oral formulation of ivermectin plus praziquantel in the reduction of nematode and cestode egg counts in horses was assessed in 273 horses under field conditions at 15 sites in North America (n = 6) and Europe (n = 9). Horses were confirmed by fecal examination to have natural infections of strongyles (100%) and tapeworms (76%). Replicates of four horses were formed at each site, and in each replicate three animals received ivermectin (0.2 mg/kg body weight) plus praziquantel (1 mg/kg body weight) oral paste and one animal remained untreated or received vehicle paste. Fecal samples were collected for fecal nematode and cestode egg counting before and 7, 8, 9, 14, 15, and 16 days after treatment. Horses treated with ivermectin plus praziquantel oral paste had significantly (P <.01) lower posttreatment strongylid and cestode egg counts (reductions of 98% or more) than controls. Combined site analyses revealed that 95% or 96% of the horses positive for cestode eggs before treatment that were treated with ivermectin plus praziquantel were negative for cestode eggs at each posttreatment fecal examination. No adverse reactions attributable to ivermectin plus praziquantel oral paste treatments were observed. The results of the studies demonstrated that ivermectin plus praziquantel paste was highly effective in reducing egg shedding by gastrointestinal nematodes and cestodes, and no adverse reactions were observed in horses treated under field conditions.     

Comparative efficacy of flubendazole chewable tablets and a tablet combination of febantel, pyrantel embonate and praziquantel against Trichuris vulpis in experimentally infected dogs

Fourteen of 23 dogs developing patent Trichuris vulpis infections by 120 days p.i. with 5000 embryonated eggs were allocated into three groups. One group was treated with flubendazole 220 mg chewable tablets (Flubenol) at the recommended dose regimen once daily for 3 days. The second group was given the recommended single treatment with a tablet containing 150 mg febantel, 144 mg pyrantel embonate and 50 mg praziquantel in combination (Drontal Plus). The third group remained untreated. All dogs were necropsied for worm counts 10 or 11 days after (first) treatment. No worms were recovered from the flubendazole treated dogs resulting in a significant worm count reduction of 100%. In contrast, 2 of 5 animals treated with the combination of febantel, pyrantel embonate and praziquantel remained infected; the geometric mean worm burden was reduced by 99.4% as compared to the control group but did not differ significantly from those of the controls.     

Efficacy of an ivermectin and pyrantel pamoate combination against adult hookworm, Ancylostoma braziliense, in dogs

A chewable tablet incorporating ivermectin and pyrantel was tested in 12 Beagle dogs for efficacy against the adult hookworm, Ancylostoma braziliense. The dogs were administered infective larvae of A braziliense orally. Twenty-one days after infection the dogs were weighed and allocated randomly to receive either an oral treatment with ivermectin and pyrantel in a beef-based chewable tablet or no treatment. The chewable tablet was a commercially available product, which was made to deliver ivermectin at 6 μg/kg and pyrantel at 5.0 mg/kg to each dog. Seven days after treatment the dogs were euthanased, necropsied, and examined for adult hookworms. At necropsy, no adult A braziliense was observed in any of the 6 treated dogs and all 6 dogs that had been left untreated were infected with adult A braziliense (range, 48 to 161). It was concluded that this combination product is 100% efficacious against adult A braziliense.     

Pharmacokinetics of a new ivermectin/praziquantel oil suspension after intramuscular administration in pigs

A new oil suspension containing 0.15% ivermectin and 15% praziquantel for intramuscular injection was developed, and corresponding pharmacokinetics studies were conducted in swine. The combination product is a white- to cream-colored oil suspension and its physical properties such as settling volume ratio, redispersibility, syringeability and flowability are well consistent with the Technical Standards by the Ministry of Agriculture of the People's Republic of China. The pharmacokinetic study consists of two parts. First, the experiments were carried out to compare the pharmacokinetic parameters of the combination product and those same products with praziquantel or ivermectin removed merely. The results showed that no significant change in the major pharmacokinetic parameters (t(1/2z), T(max), C(max), AUC(INF), TimeDur) was observed when either of the component was removed from the combination product, indicating that ivermectin and praziquantel do not interfere with each other when being used together. Second, the pharmacokinetics of the combination product were compared with those of their respective single product. The results showed that the C(max) (15.94 ng/mL) of ivermectin in combination product was 9.01 times higher than the single product, while the AUC(INF) (1925.61 ng h/mL) was 6.02 times higher. Meanwhile, the C(max) (1.48 μg/mL), AUC(INF) (17.08μgh/mL), t(1/2z) (20.25 h), TimeDur3 (42.01 h) and TimeDur4 (16.60 h) of praziquantel in combination product were improved with a factor of 5.48, 13.66, 8.58, 10.10 and 7.31 times when compared with the single product, respectively. Therefore, the efficacy of the combination product was significantly prolonged, especially for praziquantel, so that comprehensive efficacy of controlling parasites sensitive to ivermectin and praziquantel can be achieved with one-single use of it.     

Serological changes observed in horses infected with Anoplocephala perfoliata after treatment with praziquantel and natural reinfection

The serological changes in two groups of horses known to be harbouring Anoplocephala perfoliata were studied; 12 were treated with 1.5 mg/kg praziquantel and 200 microg/kg ivermectin, and 14 were treated with 200 microg/kg ivermectin. Serological and faecal analyses were carried out on each animal at intervals for 758 days. The titres of antibodies specific for A perfoliata decreased from the day of treatment to day 28 in both groups, and continued to decrease in the group treated with praziquantel and ivermectin, with the first significant decrease from the other group at day 121. From day 151 to day 295 the first significant increase in antibody levels in the group treated with both drugs was observed; no A perfoliata eggs were detected in the faeces of these animals until day 295 when five of the 10 were positive.     

Biovailability of ivermectin administered orally to dogs

The bioavailability of three formulations of ivermectin was determined following oral administration to dogs. The average peak plasma level (C _max) of ivermectin administered in the standard tablet formulation at 6 and 100 µg/kg of body weight was 2.97 and 44.31 ng/g, respectively. This suggest dose-dependent pharmacokinetics.C _max and total ivermectin bioavailability, as assessed from the area under the plasma curve (AUC), were similar between two tablet formulations of ivermectin administered at 100 µg/kg. Furthermore,C _max was similar following administration of radiolabelled ivermectin at 6 µg/kg in either a beef-based chewable formulation or in the standard tablet formulation.