Saes Isabela de Lima, Vera João H S, Fachiolli Daniele F, Yamada Paulo H, Dellaqua João V T, Saes Rafaela de Lima, Amarante Alessandro F T, Soutello Ricardo V G
UNESP - São Paulo State University, Dracena, SP, CEP 17900-000, Brazil.
FCAA - Andradina School of Agrarian Sciences, Andradina, SP, Brazil.
Vet Parasitol. 2016 Oct 15;229:90-92. doi: 10.1016/j.vetpar.2016.10.002. Epub 2016 Oct 4.
The aim of this study was to determine the time required by different anthelmintic agents to reduce strongyle egg shedding in horses. Fifty horses were divided into five homogenous groups based on faecal egg counts (FECs). Treatment groups received either ivermectin; moxidectin; fenbendazole; piperazine; or no treatment (control group). Faecal examinations were performed 4, 8, 12, 18, 24, 36 and 48h after the anthelmintic treatment. After this period, faecal samples were taken every 24h over the next 12days and finally on alternate days (48-h intervals) for another 14days until the end of the experiment (28days post-treatment). The faecal egg count reduction (FECR) was calculated based on the post-treatment mean FECs in the controls and treated animals. Eggs were absent from the faecal examinations beginning at 72h and 4days, respectively, following treatment with moxidectin or ivermectin. Piperazine showed an FECR greater than 95% from 48h up to 9days post-treatment, with the highest FECR value recorded at 7days post-treatment (98.1%). However, the FECR was lower than 90% in the last two samplings (26 and 28days post-treatment). The febendazole group presented the lowest efficacy with FECR below 90% in all samplings. The faecal cultures showed that at the beginning of the trial, all of the groups presented with mixed infections and were predominantly composed of cyathostomins (92.8%), followed by Strongylus vulgaris (5.6%) and Triodontophorus serratus (1.6%). Only cyathostomin larvae were identified following treatment with fenbendazole or piperazine. In conclusion, horses in the present study had a segment of the cyathostomin population with resistance to fenbendazole and piperazine. The strongyle population was susceptible to macrocyclic lactones, with cessation in egg shedding three and four days after treatment with moxidectin and ivermectin, respectively.
本研究的目的是确定不同驱虫剂减少马体内圆线虫虫卵排出所需的时间。根据粪便虫卵计数（FECs）将50匹马分为五个同质组。治疗组分别接受伊维菌素、莫西菌素、芬苯达唑、哌嗪治疗，或不治疗（对照组）。在驱虫治疗后4、8、12、18、24、36和48小时进行粪便检查。在此期间之后，在接下来的12天内每隔24小时采集粪便样本，最后在另外14天内每隔一天（48小时间隔）采集样本，直至实验结束（治疗后28天）。粪便虫卵计数减少率（FECR）根据对照组和治疗组动物治疗后的平均FECs计算得出。分别在用莫西菌素或伊维菌素治疗后72小时和4天开始的粪便检查中未发现虫卵。哌嗪在治疗后48小时至9天的FECR大于95%，在治疗后7天记录到最高的FECR值（98.1%）。然而，在最后两次采样（治疗后26天和28天）中，FECR低于90%。芬苯达唑组的疗效最低，在所有采样中FECR均低于90%。粪便培养表明，在试验开始时，所有组均存在混合感染，主要由杯状类圆线虫（92.8%）组成，其次是普通圆线虫（5.6%）和锯齿三齿线虫（1.6%）。在用芬苯达唑或哌嗪治疗后仅鉴定出杯状类圆线虫幼虫。总之，本研究中的马有一部分杯状类圆线虫种群对芬苯达唑和哌嗪具有抗性。圆线虫种群对大环内酯类敏感，分别在用莫西菌素和伊维菌素治疗后三天和四天停止排虫卵。
