Currently, five Bartonella species and an expanding number of Candidatus Bartonella species have globally been reported in ruminants. Likewise, different Bartonella genotypes were identified. However, studies relating to ruminant‐associated Bartonella in Brazil are scarce. The current study aimed to assess the prevalence and genetic diversity of Bartonella in cattle, buffaloes and associated ectoparasites in Brazil. For this purpose, EDTA‐blood samples from 75 cattle and 101 buffaloes were sampled. Additionally, 128 Rhipicephalus microplus and one Amblyomma sculptum ticks collected from cattle, and 197 R. microplus, one A. sculptum and 170 lice (Haematopinus tuberculatus) collected from buffaloes were included. Bartonella DNA was initially screened through an HRM real‐time PCR assay targeting the 16S–23S internal transcribed spacer (ITS), and the positive samples were submitted to an additional HRM assay targeting the ssrA gene. The HRM‐positive amplicons were sequenced, and the nucleotide identity was assessed by BLASTn. Bartonella spp.‐positive DNA samples were analysed by conventional PCR assays targeting the gltA and rpoB genes, and then, the samples were cloned. Finally, the phylogenetic positioning and the genetic diversity of clones were assessed. Overall, 21 of 75 (28%) cattle blood samples and 13 of 126 (10.3%) associated ticks were positive for Bartonella bovis. Out of 101 buffaloes, 95 lice and 188 tick DNA samples, one (1%) buffalo and four (4.2%) lice were positive for Bartonella spp. Conversely, none of the ticks obtained from buffaloes were positive for Bartonella. The Bartonella sequences from buffaloes showed identity ranging from 100% (ITS and gltA) to 94% (ssrA) with B. bovis. In contrast, the Bartonella DNA sequences from lice were identical (100%) to uncultured Bartonella sp. detected in cattle tail louse (Haematopinus quadripertusus) from Israel in all amplified genes. The present study demonstrates the prevalence of new B. bovis genotypes and a cattle lice‐associated Bartonella species in large ruminants and their ectoparasites from Brazil. These findings shed light on the distribution and genetic diversity of ruminant‐ and ectoparasite‐related Bartonella in Brazil.

中文翻译：

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巴西塞拉多大型反刍动物和相关体外寄生虫中巴尔通体物种的分子检测和遗传多样性。

目前，全球范围内已报道反刍动物中存在五种巴尔通体和数量不断增加的候选巴尔通体。同样，鉴定出不同的巴尔通体基因型。然而，巴西与反刍动物相关的巴尔通体相关的研究很少。目前的研究旨在评估巴西牛、水牛和相关体外寄生虫中巴尔通体的流行率和遗传多样性。为此，我们从 75 头牛和 101 头水牛身上采集了 EDTA 血液样本。此外，还包括从牛身上收集的 128 只小扇头蜱和 1 只Amblyomma sculptum蜱，以及从水牛身上收集的 197 只R. microplus、1 只A. sculptum和 170 只虱子 ( Haematopinus tuberculatus )。巴尔通体DNA 最初通过针对 16S-23S 内转录间隔区 (ITS) 的 HRM 实时 PCR 测定进行筛选，并将阳性样本提交给针对 ssrA 基因的额外 HRM测定。对 HRM 阳性扩增子进行测序，并通过 BLASTn 评估核苷酸同一性。通过针对gltA和rpoB基因的常规 PCR 检测对巴尔通体阳性 DNA 样本进行分析，然后对样本进行克隆。最后，评估克隆的系统发育定位和遗传多样性。总体而言，75 份牛血液样本中的 21 份 (28%) 和 126 份相关蜱中的 13 份 (10.3%)牛巴尔通体呈阳性。在 101 头水牛、95 头虱子和 188 头蜱 DNA 样本中，1 头 (1%) 头水牛和 4 头头虱 (4.2%)巴尔通体呈阳性。相反，从水牛获得的蜱中没有巴尔通体呈阳性。来自水牛的巴尔通体序列与牛巴尔通体的同一性范围为 100%（ITS 和gltA）至 94%（ssrA）。相比之下，来自虱子的巴尔通体DNA 序列与未培养的巴尔通体相同 (100%) 。在来自以色列的牛尾虱（Haematopinus fourpertusus）中检测到所有扩增基因。本研究表明，新的牛双歧杆菌基因型和与牛虱相关的巴尔通体在来自巴西的大型反刍动物及其体外寄生虫中普遍存在。这些发现揭示了巴西反刍动物和体外寄生虫相关巴尔通体的分布和遗传多样性。