Choi B K, Nattermann H, Grund S, Haider W, Göbel U B
Institut für Mikrobiologie und Hygiene, Universitätsklinikum Charité, Humboldt-Universität zu Berlin, Germany.
Int J Syst Bacteriol. 1997 Jan;47(1):175-81. doi: 10.1099/00207713-47-1-175.
Digital dermatitis (DD), first described in 1974 by Cheli and Mortellaro (R. Cheli and C. Mortellaro, p. 208-213, in Proceedings of the 8th International Conference on Diseases of Cattle, 1974), is a major problem in diary cows and beef cattle causing significant economic losses worldwide. Lesions are typically found at the volar skin proximal to the heel bulbs. Microscopic examination of biopsies or touch preparations of these lesions revealed a variety of different bacterial morphotypes including significant numbers of spirochetes which often represent the predominant morphotype. We used comparative 16S rRNA sequence analysis to determine the diversity and phylogeny of these hitherto unclassified DD spirochetes. Results indicate that those lesions looked at so far contained at least five spirochetal phylotypes, all clustering within the genus Treponema. Phylotype DDKL-4 was nearly identical (99.4% similarity) to that of a nonpathogenic human treponeme, T. phagedenis. Two phylotypes DDKL-3 and DDKL-13 were closely related to those from treponemes commonly found in human periodontitis lesions, i.e., T. denticola and T. vincetii, exhibiting 95 and 98% similarity, respectively. The other two phylotypes, DDKL-12 and DDKL-20, had no close relatives to any cultivable treponemal species but clustered to previously described group IV oral treponemes. Preliminary analysis using in situ hybridization with fluorescently labeled oligonucleotide probes against smears from DD biopsies revealed that from all lesions analyzed so far, T. denticola-like spirochetes were detected in the highest proportion of all spirochetal morphotypes.
数字皮炎（DD）于1974年由切利和莫泰拉罗首次描述（R.切利和C.莫泰拉罗，《第八届国际牛病会议论文集》，第208 - 213页，1974年），是奶牛和肉牛养殖中的一个主要问题，在全球范围内造成重大经济损失。病变通常出现在脚跟球部近端的掌侧皮肤。对这些病变的活检组织或触片进行显微镜检查发现了多种不同的细菌形态类型，包括大量螺旋体，螺旋体常常是主要的形态类型。我们使用比较16S rRNA序列分析来确定这些迄今未分类的DD螺旋体的多样性和系统发育。结果表明，到目前为止所观察的那些病变至少包含五种螺旋体系统发育型，它们都聚集在密螺旋体属内。系统发育型DDKL - 4与一种非致病性人类密螺旋体——溃蚀性密螺旋体几乎相同（相似度为99.4%）。两种系统发育型DDKL - 3和DDKL - 13与常见于人类牙周炎病变中的密螺旋体密切相关，即齿垢密螺旋体和文森特密螺旋体，相似度分别为95%和98%。另外两种系统发育型DDKL - 12和DDKL - 20与任何可培养的密螺旋体物种都没有近亲关系，但聚集到先前描述的IV组口腔密螺旋体中。使用针对DD活检涂片的荧光标记寡核苷酸探针进行原位杂交的初步分析表明，在所有分析的病变中，齿垢密螺旋体样螺旋体在所有螺旋体形态类型中检测比例最高。
