Malczewski A, Wescott R B, Spratling B M, Gorham J R
Am J Vet Res. 1975 Nov;36(11):1671-5.
The occurrence of internal parasites in Washinton cattle was estimated. During the survey period in 1972 and 1973, more than 3,700 fecal samples from 29 herds and 4 feedlots, and viscera from 55 cattle were examined. The percentage of fecal samples with parasite eggs or oocysts from herds was as follows: oocysts, 77%; "strongyline" eggs, 44%; Nematodirus eggs, 3%; Moniezia eggs, 3%; Fasciola eggs, 2%; Trichuris eggs, 2%; and Dictyocaulus larvae, 1%. The fecal samples from feedlots contained principally strongyline eggs which varied markedly in numbers among groups of cattle in the lots. The predominant parasite in viscera was Ostertagia spp, which was recovered from all of the cattle examined. Other parasites identified in the survey were found less frequently in these examinations. Cattle in dairy and beef operations utilizing irrigated pastures were particularly prone to Fasciola infections, and more strongyline eggs were observed there than in fecal samples from other management systems. Seasonal fluctuations in numbers of strongyline and Fasciola eggs were pronounced.
对华盛顿州牛体内寄生虫的感染情况进行了评估。在1972年和1973年的调查期间，对来自29个牛群和4个饲养场的3700多个粪便样本以及55头牛的内脏进行了检查。各牛群粪便样本中带有寄生虫卵或卵囊的比例如下：卵囊，77%；“类圆线虫属”卵，44%；细颈线虫属卵，3%；莫尼茨绦虫卵，3%；肝片吸虫卵，2%；鞭虫卵，2%；以及网尾线虫幼虫，1%。饲养场的粪便样本主要含有类圆线虫属卵，不同牛群中的数量差异显著。内脏中最主要的寄生虫是奥斯特线虫属，所有检查的牛只中均发现了该寄生虫。调查中鉴定出的其他寄生虫在这些检查中出现的频率较低。利用灌溉牧场的奶牛场和肉牛场的牛特别容易感染肝片吸虫，并且在那里观察到的类圆线虫属卵比其他管理系统的粪便样本中更多。类圆线虫属和肝片吸虫卵的数量存在明显的季节性波动。
