Lyons E T, Tolliver S C, Rathgeber R A, Collins S S
Department of Veterinary Science, University of Kentucky, Gluck Equine Research Center, Lexington, KY 40546-0099, USA.
Parasitol Res. 2007 Feb;100(3):473-8. doi: 10.1007/s00436-006-0289-6. Epub 2006 Sep 30.
Foals (79), born in 2004 on three thoroughbred horse farms (C, M, and S) in central Kentucky, were fed pyrantel tartrate daily, beginning at about 3 months of age. In addition, other parasiticides [fenbendazole (FBZ), ivermectin (IVM) alone or with praziquantel (PRAZ), oxibendazole (OBZ), pyrantel pamoate (PRT), and moxidectin (MOX)] were given periodically. All treatments were administered by farm personnel. Over a 14-month period, from May 2004 to July 2005, collections (n=989) of feces were made from the foals for determination of presence of internal parasite eggs/oocysts by qualitative and/or quantitative methods. Conclusions on drug activity are based necessarily on considering the combined effect of pyrantel tartrate and the other compounds. For small strongyles, this was related to which specific additional compound was given. Based on the percentage of foals with strongyle-egg-positive feces and/or the level of eggs per gram of feces (EPG) counts for the foals after treatment, drug activity on small strongyles was highest to lowest for MOX, IVM and IVM/PRAZ, FBZ, OBZ, PRT, and FBZ (2x for 5 days). The macrocyclic lactones (MOX and IVM) were highly superior to the other compounds. Some of the strongyle counts were high (over 2,000), especially on one farm (S), during periods when foals received only pyrantel tartrate, but a few days after administration of therapeutic dose rates of the drugs IVM or MOX, they were negative or very low. Ascarid eggs were present in feces of three foals after treatment with a combination of IVM and PRAZ. The qualitative method was more efficient than the quantitative method in detection of ascarid and strongyle eggs in the feces. Prevalence of eggs of ascarids (Parascaris equorum) was low (0, 4, and 31%), of strongyles high (80, 100, and 100%), of Strongyloides westeri very low (only one infected foal), and oocysts of Eimeria leuckarti medium to high (36, 41, and 85%) for the three farms, C, M, and S, respectively. It is uncertain whether the low ascarid prevalence was from activity of pyrantel tartrate and/or the other drugs or to a limited source of infective eggs.
2004年出生在肯塔基州中部三个纯种马养殖场（C、M和S）的79匹小马驹，从大约3月龄开始每天饲喂酒石酸噻嘧啶。此外，还定期给予其他驱虫剂[芬苯达唑（FBZ）、伊维菌素（IVM）单独使用或与吡喹酮（PRAZ）联用、奥苯达唑（OBZ）、双羟萘酸噻嘧啶（PRT）和莫西菌素（MOX）]。所有治疗均由养殖场工作人员进行。在2004年5月至2005年7月的14个月期间，从这些小马驹采集粪便样本（n = 989），通过定性和/或定量方法测定体内寄生虫卵/卵囊的存在情况。关于药物活性的结论必然基于考虑酒石酸噻嘧啶和其他化合物的联合作用。对于小型圆线虫，这与给予哪种特定的其他化合物有关。根据治疗后粪便中带有圆线虫卵阳性的小马驹百分比和/或每克粪便中虫卵数（EPG），药物对小型圆线虫的活性从高到低依次为莫西菌素、伊维菌素和伊维菌素/吡喹酮、芬苯达唑、奥苯达唑、双羟萘酸噻嘧啶以及芬苯达唑（5天内2倍剂量）。大环内酯类药物（莫西菌素和伊维菌素）比其他化合物效果好得多。在小马驹仅接受酒石酸噻嘧啶治疗期间，一些圆线虫计数很高（超过2000），特别是在一个养殖场（S），但在给予伊维菌素或莫西菌素治疗剂量几天后，计数呈阴性或非常低。在用伊维菌素和吡喹酮联合治疗后，三头小马驹的粪便中出现了蛔虫卵。在检测粪便中的蛔虫和圆线虫卵方面，定性方法比定量方法更有效。三个养殖场C、M和S的蛔虫（马副蛔虫）卵感染率较低（分别为0、4和31%），圆线虫感染率较高（分别为80、100和100%），类圆线虫感染率非常低（仅一匹感染小马驹），鲁氏艾美耳球虫卵囊感染率为中到高（分别为36、41和85%）。尚不确定蛔虫感染率低是由于酒石酸噻嘧啶和/或其他药物的作用，还是由于感染性虫卵来源有限。
