Abstract The aim of this study was to evaluate the efficacy and the cost-benefit ratio of the treatment with a single-dose of toltrazuril 5% to control Eimeria spp. infection in lambs kept at pasture in condition favorable to coccidiosis. This experiment was designed after a lamb of the target-flock died due to acute diarrhea caused by clinical coccidiosis. Thirty-two lambs of both genders and age approximately 6–7 months were randomized between two groups, balanced by oocysts per gram of feces (OPG) count and live weight. The group TOL was treated with toltrazuril 5% in a single dose and group CON was the untreated (control). Individual feces were collected weekly from day 0 until day 84 after the onset of the treatment. Lambs were weighed at days 0, 84, and 126; and the costs of the treatment were calculated. Efficacy of the treatment using toltrazuril 5% was higher than 95 % until day 21. Treated lambs become re-infected on day 28. E. ahsata was the most frequent species found in the lambs feces. There was no significant diff ;erence in weight gain between the groups. The total cost of the treatment was U$2.32 per animal, and the economic loss caused by death of lamb was U$38.4. Thus, although the treatment with a single-dose of toltrazuril has been effective against Eimeria spp. infection, it was not considered economically feasible in lambs with subclinical coccidiosis. However, the treatment with toltrazuril can become a cost-effective option to prevent clinical coccidiosis and deaths of lambs caused by Eimeria spp. infection at pasture system.

中文翻译：

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单剂量托曲珠利对艾美球虫的影响。在牧场饲养的羔羊中，有利于球虫病

摘要 本研究的目的是评估单剂量 5% 托曲珠利治疗艾美球虫的疗效和成本效益比。牧场饲养的羔羊感染球虫病。本实验是在目标羊的一只羔羊因临床球虫病引起的急性腹泻死亡后设计的。将 32 只性别和年龄约为 6-7 个月的羔羊随机分为两组，通过每克粪便的卵囊数 (OPG) 计数和活重进行平衡。TOL 组用 5% 托曲珠利单剂量治疗，CON 组为未治疗组（对照）。从治疗开始后的第 0 天至第 84 天，每周收集个体粪便。羔羊在第 0、84 和 126 天称重；并计算治疗费用。直到第 21 天，使用 toltrazuril 5% 的处理效率高于 95%。经过处理的羔羊在第 28 天再次感染。E.ahsata 是在羔羊粪便中发现的最常见的物种。各组之间的体重增加没有显着差异。治疗总费用为每头2.32美元，羔羊死亡造成的经济损失为38.4美元。因此，虽然用单剂量的托曲珠利治疗对艾美球虫有效。感染，在患有亚临床球虫病的羔羊中被认为在经济上不可行。然而，托曲珠利治疗可以成为预防艾美球虫引起的临床球虫病和羔羊死亡的一种具有成本效益的选择。牧场系统感染。ahsata 是羔羊粪便中最常见的物种。各组之间的体重增加没有显着差异。治疗总费用为每头2.32美元，羔羊死亡造成的经济损失为38.4美元。因此，虽然用单剂量的托曲珠利治疗对艾美球虫有效。感染，在患有亚临床球虫病的羔羊中被认为在经济上不可行。然而，托曲珠利治疗可以成为预防艾美球虫引起的临床球虫病和羔羊死亡的一种具有成本效益的选择。牧场系统感染。ahsata 是羔羊粪便中最常见的物种。各组之间的体重增加没有显着差异。治疗总费用为每头2.32美元，羔羊死亡造成的经济损失为38.4美元。因此，虽然用单剂量的托曲珠利治疗对艾美球虫有效。感染，在患有亚临床球虫病的羔羊中被认为在经济上不可行。然而，托曲珠利治疗可以成为预防艾美球虫引起的临床球虫病和羔羊死亡的一种具有成本效益的选择。牧场系统感染。因此，虽然用单剂量的托曲珠利治疗对艾美球虫有效。感染，在患有亚临床球虫病的羔羊中被认为在经济上不可行。然而，托曲珠利治疗可以成为预防艾美球虫引起的临床球虫病和羔羊死亡的一种具有成本效益的选择。牧场系统感染。因此，虽然用单剂量的托曲珠利治疗对艾美球虫有效。感染，在患有亚临床球虫病的羔羊中被认为在经济上不可行。然而，托曲珠利治疗可以成为预防艾美球虫引起的临床球虫病和羔羊死亡的一种具有成本效益的选择。牧场系统感染。