Catchpole J, Gregory M W
Parasitology. 1985 Aug;91 ( Pt 1):45-52. doi: 10.1017/s003118200005650x.
Ten colostrum-deprived, coccidia-free lambs were reared artificially in indoor cages. At 4 weeks of age they were allocated to 5 groups of 2: Groups 1-3 received 10(4), 10(5) and 10(6) sporulated oocysts of Eimeria crandallis/lamb respectively, each as a single inoculum. Group 4 lambs received daily doses increasing over a 4-week period. Groups 1-3 showed diarrhoea and weight loss from about day 14, followed by slow recovery from about day 30. The diarrhoea was accompanied by a wave of oocyst output and a reduction in serum albumin and plasma alkaline phosphatase activity. One lamb in group 4 died of an unrelated condition on day 15; the other showed no clinical effect of the oocyst inoculations and its oocyst output was related only to the first week or two of inoculation. Lambs in Group 1 showed no clinical effect or oocyst output following challenge with 10(6) oocysts on day 28. E. crandallis showed high pathogenicity and immunogenicity. Its pathogenicity was not closely related to infecting dose within the range 10(4)-10(6).
十只未哺初乳、无球虫的羔羊在室内笼子中人工饲养。4周龄时，它们被分成5组，每组2只：第1 - 3组分别给每只羔羊接种10⁴、10⁵和10⁶个已孢子化的克兰德艾美耳球虫卵囊，均为单次接种。第4组羔羊在4周内每天递增剂量接种。第1 - 3组从大约第14天开始出现腹泻和体重减轻，随后从大约第30天开始缓慢恢复。腹泻伴随着一波卵囊排出，血清白蛋白和血浆碱性磷酸酶活性降低。第4组中有一只羔羊在第15天死于无关疾病；另一只未表现出卵囊接种的临床效应，其卵囊排出仅与接种的头一两周有关。第1组的羔羊在第28天用10⁶个卵囊攻毒后未表现出临床效应或卵囊排出。克兰德艾美耳球虫表现出高致病性和免疫原性。在10⁴ - 10⁶的范围内，其致病性与感染剂量没有密切关系。
