Svensson C, Uggla A, Pehrson B
Experimental Station, Veterinary Institute, Skara, Sweden.
Vet Parasitol. 1994 May;53(1-2):33-43. doi: 10.1016/0304-4017(94)90014-0.
Large numbers of oocysts of Eimeria alabamensis have been found in the faeces of calves suffering from diarrhoea shortly after being turned out to pasture. To investigate the source and clinical significance of this coccidial infection, the numbers of oocysts excreted, the consistency of the faeces and the growth rates of four groups of 12 calves were compared. Group I calves were kept indoors and their diet was unchanged, Group II calves were turned out onto a previously ungrazed pasture, Group III calves were turned out onto a permanent pasture and Group IV calves were kept indoors and fed cut grass from a previously ungrazed field. Eight days after the animals were turned out there was an almost 1000-fold increase in the numbers of oocysts in the faeces of Group III calves, the dominant species being E. alabamensis, but there were only minor fluctuations in the numbers of oocysts excreted by the other groups. It was therefore concluded that the source of the infection was oocysts that had overwintered on the permanent pasture. Most of the calves in Group III developed watery diarrhoea 5 days after turnout, but there was only a slight softening of the faeces of the calves in Groups II and IV at about the same time. The faeces of the calves in Group I was of firm consistency throughout the trial. The calves in Group III lost 18 kg during the 24 day period following turnout, whereas the calves in the other groups gained between 6 and 18 kg.
在刚被赶到牧场不久就患腹泻的犊牛粪便中，发现了大量阿拉巴马艾美耳球虫的卵囊。为了调查这种球虫感染的来源和临床意义，对四组每组12头犊牛排出的卵囊数量、粪便稠度和生长速率进行了比较。第一组犊牛饲养在室内，饮食不变；第二组犊牛被赶到以前未放牧过的牧场上；第三组犊牛被赶到永久牧场上；第四组犊牛饲养在室内，喂以来自以前未放牧过田地的割草。动物被放出8天后，第三组犊牛粪便中的卵囊数量增加了近1000倍，优势种为阿拉巴马艾美耳球虫，但其他组排出的卵囊数量只有轻微波动。因此得出结论，感染源是在永久牧场上越冬的卵囊。第三组中的大多数犊牛在放出5天后出现水样腹泻，但第二组和第四组的犊牛在大约同一时间粪便只是稍有变软。在整个试验期间，第一组犊牛的粪便一直很坚实。第三组犊牛在放出后的24天内体重减轻了18千克，而其他组的犊牛体重增加了6至18千克。
