Environmental Microbial and Food Safety Laboratory, Animal and Natural Resources Institute, Agricultural Research Service, United States Department of Agriculture, 10300 Baltimore Avenue, Beltsville, MD 20705, USA.
Vet Parasitol. 2010 Aug 27;172(1-2):23-32. doi: 10.1016/j.vetpar.2010.04.028. Epub 2010 Apr 28.
A new species, Cryptosporidium ubiquitum, previously identified as the Cryptosporidium cervine genotype and infrequently as the cervid, W4 or genotype 3 genotype, is described. In published studies this genotype was reported in wild and domesticated ruminants, rodents, carnivores and primates including humans. In the present study oocysts were found in feces from a captive prehensile-tailed porcupine and her infant. Oocysts from the porcupine were transmitted to 4 boer goats. Oocysts from the goats were transmitted to a calf (calf 1) and oocysts from calf 1 were transmitted to gerbils and BALB/c mouse pups. Calf 2 housed near calf 1 became contaminated and excreted oocysts of C. ubiquitum. Oocysts collected from calf 2 were transmitted to a calf 3. When calf 2 stopped excreting C. ubiquitum oocysts it was challenged with oocysts of C. parvum and became infected, indicating a lack of cross-species immunity. Oocysts of C. ubiquitum from calf 1 measured 4.71-5.32 microm x 4.33-4.98 microm (mean=5.04 microm x4.66 microm) with a length/width shape index of 1.08 (n=50). Purified PCR products of the SSU rRNA, actin and COWP genes were sequenced and analysis of the 3 unlinked loci demonstrated the new species to be distinct from all other species and also demonstrated a lack of recombination, providing further evidence of species status. Based on morphological, molecular and biological data, this geographically widespread parasite infectious for a wide range of mammalian hosts is recognized as a new species and is named C. ubiquitum.
一种新的物种，Cryptosporidium ubiquitum，以前被鉴定为鹿源 Cryptosporidium cervine 基因型，并且偶尔也被鉴定为鹿、W4 或基因型 3 基因型。在已发表的研究中，这种基因型已在野生和家养反刍动物、啮齿动物、食肉动物和灵长类动物（包括人类）中报道过。在本研究中，在一只圈养的食蚁兽及其幼崽的粪便中发现了卵囊。从食蚁兽中分离出的卵囊被传代到 4 只布尔山羊。从山羊中分离出的卵囊被传代到一只小牛（小牛 1），从小牛 1 中分离出的卵囊被传代到沙鼠和 BALB/c 幼鼠中。靠近小牛 1 饲养的小牛 2 被污染并排出了 C. ubiquitum 的卵囊。从小牛 2 中收集的卵囊被传代到小牛 3。当小牛 2 停止排出 C. ubiquitum 卵囊时，它被挑战用 C. parvum 的卵囊感染，表明缺乏跨物种免疫力。从小牛 1 中分离出的 C. ubiquitum 卵囊大小为 4.71-5.32 µm x 4.33-4.98 µm（平均值=5.04 µm x 4.66 µm），长宽比形状指数为 1.08（n=50）。对 SSU rRNA、肌动蛋白和 COWP 基因的纯化 PCR 产物进行测序，对 3 个不相关的基因座进行分析，表明该新物种与所有其他物种都不同，也表明不存在重组，进一步证明了其物种地位。基于形态学、分子生物学和生物学数据，这种在地理上广泛分布的寄生虫感染范围广泛的哺乳动物宿主，被认为是一种新的物种，并被命名为 C. ubiquitum。
