Rehbein Steffen, Knaus M, Visser M, Rauh R, Yoon S
Merial GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, 83101, Rohrdorf, Germany.
Merial Inc., 3239 Satellite Blvd., Duluth, GA, 30096, USA.
Parasitol Res. 2016 Dec;115(12):4639-4648. doi: 10.1007/s00436-016-5256-2. Epub 2016 Sep 15.
Gastrointestinal and pulmonary nematode infections are affecting the health and productivity of grazing cattle worldwide. To evaluate the effects of a single treatment with ivermectin long-acting injection (IVM LAI; IVOMEC® GOLD, Merial; 3.15 % ivermectin w/v) in first-grazing season cattle, two studies were conducted under continued stocking conditions for 84 or 100 days in Bavaria, Germany. Each study involved 68 naturally infected, approximately 4- to 6-month-old Brown Swiss bull calves. Animals were blocked based on pretreatment body weights. Within each block of four animals, animals were randomly assigned to treatments: one to saline (control) and three to IVM LAI. Treatments were injected at 1 mL/50 kg body weight subcutaneously in front of the shoulder. Animals in both studies were managed as one herd each grazing together. Cattle were weighed and fecal samples were collected pretreatment and at intervals thereafter for determination of weight gain and treatment efficacy, respectively. Fecal examination including composite fecal culture indicated the presence of nematodes of the genera Cooperia (dominating), Haemonchus, Nematodirus, Ostertagia, Strongyloides, Trichostrongylus, Trichuris, and Dictyocaulus, and Moniezia cestodes in the cattle. Following treatment, IVM LAI-treated cattle did not shed any Dictyocaulus larvae for 84 days while controls continued to pass larvae. Compared to the controls, IVM LAI-treated cattle had significantly (p < 0.01) lower strongylid egg counts at each occasion. Percentage reductions were ≥94 % up to 70 days after treatment and were ≥83.9 and 58.9 % at 84 and 100 days. Over the 84- or 100-day study periods, IVM LAI-treated cattle gained significantly more weight than the controls: 22.7 and 12.4 kg, respectively. The two studies demonstrated a high efficacy of IVM LAI against gastrointestinal and pulmonary nematode infections under field conditions in Germany which was associated with significant benefit as to weight gain.
胃肠道和肺部线虫感染正影响着全球放牧牛的健康和生产力。为评估伊维菌素长效注射液（IVM LAI；IVOMEC® GOLD，梅里亚公司；3.15%伊维菌素，重量/体积）单次治疗对首次放牧季节牛的影响，在德国巴伐利亚州持续放牧条件下进行了两项为期84天或100天的研究。每项研究涉及68头自然感染的、约4至6月龄的瑞士褐牛公牛犊。动物根据预处理体重进行分组。在每组四只动物中，动物被随机分配至各处理组：一组接受生理盐水（对照），三组接受IVM LAI。按1 mL/50 kg体重在肩部前方皮下注射给药。两项研究中的动物均作为一个牛群一起放牧管理。在预处理时以及此后定期对牛称重并采集粪便样本，分别用于测定体重增加和治疗效果。包括混合粪便培养的粪便检查表明，牛体内存在库珀属（为主）、血矛线虫属、细颈线虫属、奥斯特他线虫属、类圆线虫属、毛圆线虫属、毛首线虫属和网尾线虫属的线虫，以及莫尼茨绦虫。治疗后，接受IVM LAI治疗的牛在84天内未排出任何网尾线虫幼虫，而对照组继续排出幼虫。与对照组相比，接受IVM LAI治疗的牛在每次检测时的圆线虫卵计数均显著更低（p < 0.01）。治疗后70天内虫卵减少百分比≥94%，在84天和100天时分别≥83.9%和58.9%。在84天或100天的研究期间，接受IVM LAI治疗的牛体重增加显著高于对照组，分别增加了22.7 kg和12.4 kg。两项研究表明，在德国的田间条件下，IVM LAI对胃肠道和肺部线虫感染具有高效，且与体重增加的显著益处相关。
