McDougald L R
J Protozool. 1979 Feb;26(1):109-13. doi: 10.1111/j.1550-7408.1979.tb02741.x.
Attempted infection of 2 young lambs with oocysts of Eimeria christenseni from a goat was unsuccessful. Negative results were obtained also when young kids were fed oocysts of Eimeria ninakohlyakimovae from sheep. There was no difficulty in infecting lambs with the sheep coccidium resembling E. ninakohlyakimovae nor goats with the goat coccidium E. christenseni. Oocysts from the goat measured 38.4 X 26.7 microns, but were easily distinguished from Eimeria ahsata from the sheep by sporocyst size and shape, and from Eimeria ovina by oocyst size. Eimeria ninakohlyakimovae-like oocysts from sheep averaged 23.0 X 18.2 microns and were morphologically indistinguishable from previously reported goat coccidia. Since no cross infections of sheep and goats could be accomplished with oocysts of Eimeria sp. characteristic of one or the other host, I concluded that sheep coccidia previously known as E. ninakohlykimovae are distinct from morphologically similar goat coccidia and therefore constitute a separate species. Since the name E. ninakohlyakimovae was first used for coccidia from the goat, the sheep coccidium is renamed Eimeria ovinoidalis with oocyst structure and endogenous stages similar to those previously described from the sheep.
尝试用来自山羊的克里斯滕艾美耳球虫卵囊感染2只幼龄羔羊，但未成功。给幼龄山羊投喂来自绵羊的尼氏艾美耳球虫卵囊，结果也呈阴性。用类似尼氏艾美耳球虫的绵羊球虫感染羔羊以及用山羊球虫克里斯滕艾美耳球虫感染山羊均无困难。来自山羊的卵囊大小为38.4×26.7微米，但根据孢子囊大小和形状可轻松与来自绵羊的阿氏艾美耳球虫区分开来，根据卵囊大小可与绵羊艾美耳球虫区分开来。来自绵羊的类似尼氏艾美耳球虫的卵囊平均大小为23.0×18.2微米，在形态上与先前报道的山羊球虫无法区分。由于用一种或另一种宿主特有的艾美耳球虫卵囊无法实现绵羊和山羊之间的交叉感染，我得出结论，先前称为尼氏艾美耳球虫的绵羊球虫与形态相似的山羊球虫不同，因此构成一个单独的物种。由于尼氏艾美耳球虫这个名称最初用于山羊球虫，因此将绵羊球虫重新命名为类绵羊艾美耳球虫，其卵囊结构和内发育阶段与先前从绵羊中描述的相似。
