Abstract The objective of this study was to evaluate the genetic diversity of Moraxella bovis and Moraxella bovoculi bacteria isolated from infectious bovine keratoconjunctivitis (IBK) outbreaks in the state of Rio Grande do Sul, Brazil. The genetic diversity among Moraxella spp. was evaluated by RAPD-PCR, JWP1-JWOPA07-PCR, ERIC-PCR and by sequencing the 16S-23S intergenic regions. Based on the dendrogram, two genetically differentiated clades were observed; 14 isolates were classified as M. bovis and 17 as M. bovoculi. Genetic distances between the M. bovis samples ranged from 0.0379 to 0.4285, while for M. bovoculi the dissimilarities ranged from zero to 0.7297. Alternatively, based on sequencing analyses of the 16S-23S intergenic region, M. bovis and M. bovoculi isolates were grouped into the same two different clades, but it was not possible to differentiate between isolates within clades. PCR techniques were demonstrated to be a satisfactory tool to unravel the genetic variability among Moraxella spp., while sequencing of the 16S-23S intergenic region was only able to differentiate two species of the Moraxella genus. Despite sampling geographically close regions, we demonstrate considerable genetic diversity in M. bovis and M. bovoculi strains and genetically distinct M. bovis strains co-infecting the same animal.

中文翻译：

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来自巴西南部传染性牛角结膜炎 (IBK) 暴发的牛莫拉菌和牛莫拉菌分离株之间的遗传差异

摘要 本研究的目的是评估从巴西南里奥格兰德州爆发的传染性牛角膜结膜炎 (IBK) 暴发中分离出的牛莫拉菌和牛莫拉菌细菌的遗传多样性。莫拉氏菌属之间的遗传多样性。通过 RAPD-PCR、JWP1-JWOPA07-PCR、ERIC-PCR 和对 16S-23S 基因间区域进行测序来评估。基于树状图，观察到两个遗传分化的进化枝；14 个分离株被分类为牛分枝杆菌，17 个被分类为牛分枝杆菌。M. bovis 样本之间的遗传距离范围从 0.0379 到 0.4285，而 M. bovoculi 的差异范围从 0 到 0.7297。或者，基于 16S-23S 基因间区域的测序分析，牛分枝杆菌和牛分枝杆菌分离株被分为相同的两个不同的进化枝，但不可能区分进化枝内的分离株。PCR 技术被证明是一种令人满意的工具，可以解开 Moraxella spp. 之间的遗传变异性，而 16S-23S 基因间区域的测序只能区分 Moraxella 属的两个物种。尽管在地理上很近的区域取样，但我们在牛分枝杆菌和牛分枝杆菌菌株以及共同感染同一动物的遗传上不同的牛分枝杆菌菌株中证明了相当大的遗传多样性。