Department of Parasitology and Invasive Diseases, University of Life Sciences in Lublin, 12 Akademicka, 20-033, Lublin, Poland.
INRAE/U. de Tours, UMR1282 ISP, 37380, Nouzilly, France.
Acta Vet Scand. 2020 Jun 5;62(1):28. doi: 10.1186/s13028-020-00526-2.
Parascaris spp. are major gastro-intestinal nematodes that infect foals and can lead to respiratory symptoms, poor growth, and in some cases obstruction of the small intestine and death. Ivermectin resistance has been reported for Parascaris spp. in many countries. In Poland, the knowledge of the level of resistance against ivermectin in Parascaris spp. is limited. The aim of this study was to examine the efficacy of ivermectin against Parascaris spp. in foals from south-eastern Poland. Foals (n = 225 = reared in 7 stud farms) were treated orally with ivermectin paste. Faecal samples were collected from the rectum of each foal or from the environment straight after defaecation on 1 day prior and 2 weeks after deworming. A faecal egg count (FEC) was performed using the McMaster method with a minimum detection limit of 50 eggs/g. FEC reduction (FECR) was calculated using the Faecal Egg Count Reduction Test. The statistical analysis was limited to foals excreting more than 150 eggs/g before treatment and to stud farms with at least 6 foals excreting at or above this level. Confidence intervals were determined by 1000 bootstraps at farm level and the contribution of sex and age to FECR was quantified using a generalized equation estimation procedure. Parascaris spp. eggs were found in 40% of the foals. Following ivermectin treatment, Parascaris spp. eggs were identified in 28.4% of the foals. The mean estimated FECR ranged from 44% to 97% and average efficacy was 49.3%. FECR was more pronounced in older foals (P-values = 0. 003). The FECR was more pronounced in males than in females (P value = 0.028). This study is the first to indicate a reduced efficacy of ivermectin against Parascaris spp. in foals in Poland.
副蛔虫是主要的胃肠道线虫，感染马驹可导致呼吸道症状、生长不良，在某些情况下还会导致小肠阻塞和死亡。副蛔虫对伊维菌素的耐药性已在许多国家得到报道。在波兰，对副蛔虫对伊维菌素的耐药水平知之甚少。本研究旨在检查伊维菌素对波兰东南部马驹副蛔虫的疗效。马驹（n = 225 = 在 7 个马场饲养）口服伊维菌素膏剂进行治疗。在驱虫前 1 天和驱虫后 2 周，从每匹马驹的直肠或刚排便的环境中采集粪便样本。使用麦克马斯特法进行粪便卵计数（FEC），最低检测限为 50 个卵/g。使用粪便卵计数减少试验（FECR）计算 FEC 减少率。统计分析仅限于治疗前排泄超过 150 个卵/g 的马驹，以及至少有 6 匹马驹排泄在或高于这一水平的马场。在农场水平上通过 1000 次引导确定置信区间，并使用广义方程估计程序量化性别和年龄对 FECR 的贡献。40%的马驹中发现了副蛔虫卵。在伊维菌素治疗后，28.4%的马驹中发现了副蛔虫卵。估计的平均 FECR 范围为 44%至 97%，平均疗效为 49.3%。年龄较大的马驹的 FECR 更明显（P 值=0.003）。雄性马驹的 FECR 比雌性马驹更明显（P 值=0.028）。本研究首次表明，波兰马驹副蛔虫对伊维菌素的疗效降低。
