绵羊γ-疱疹病毒2 (OvHV-2) 属于Macavirus属，引起了绵羊相关恶性慢性咽炎 (SA-MCF)，这是一种影响马和其他许多有蹄类动物的致命的淋巴增殖性疾病。本研究描述了墨西哥发生的SA-MCF爆发以及通过产生细胞核内包涵体、合胞体、免疫荧光 (IF)、免疫细胞化学 (ICC)、免疫组织化学 (IHC)、端点聚合酶链反应 (PCR) 和ORF75基因的部分测序，在原代兔睾丸培养物中鉴定了OvHV-2病毒。参与此次爆发的动物口腔前庭和舌头出现粘膜龈溃疡、多唾液、角膜混浊、食物摄入减少和体重减轻等不同程度临床症状。这些临床症状和组织病理学发现表明了SA-MCF的诊断。患病动物的抗凝血血液样本中收集了血浆分数，并进行了PCR分析。阳性的血浆分数被用于接种兔睾丸原代细胞培养物以鉴定病毒。在感染后的48至72小时内，观察到具有病毒细胞病理效应特征的小聚集反脉冲细胞。此外，在接种的原代培养细胞中鉴定出细胞核内酸性充满酸性胞质包涵体 (IBs)，并且胞质对OvHV-2的超免疫兔抗血清呈现免疫反应性。此外，在患病鹿的肝脏组织切片中，也通过同一种兔超免疫血清鉴定出具有免疫反应性的细胞核旁链 IBs。获得的序列与GenBank中报告的OvHV-2序列进行了比对，核苷酸一致性高于98%。基于本研究提供的证据，我们得出结论：墨西哥Queretaro州Tequisquiapan市的SA-MCF爆发是由OvHV-2引起的。这是第二项报告表明马对OvHV-2感染具有敏感性并能够发展SA-MCF。我们首次在墨西哥的马和偶蹄类动物的血浆中发现了OvHV-2的存在。 版权：© 2023 Madrigal-Valencia等。本文为开放获取文章，按照知识共享署名协议，允许在任何媒介中无限制使用、分发和复制，只要原作者和来源得到公认。

Ovine gammaherpesvirus 2 (OvHV-2), a member of the genus Macavirus, causes sheep-associated malignant catarrhal fever (SA-MCF), a fatal lymphoproliferative disease affecting a wide variety of ungulates in addition to horses. This study described an outbreak of SA-MCF in Mexico and the identification of the OvHV-2 virus in primary rabbit testis cultures through the generation of intranuclear inclusion bodies, syncytia, immunofluorescence (IF), immunocytochemistry (ICC), immunohistochemistry (IHC), endpoint polymerase chain reaction (PCR), and partial sequencing of the ORF75 gene. The animals involved in this outbreak showed mucogingival ulcers in the vestibule of the mouth and tongue, hypersalivation, corneal opacity, reduced food consumption, and weight loss of variable severity. These clinical signs and the histopathological findings suggested the diagnosis of SA-MCF. Buffy coat fractions from the anticoagulated blood samples of ill animals were collected and analyzed by PCR. Positive buffy coats were used to inoculate the primary cell cultures of rabbit testis to identify the virus. Small clusters of refractile cytomegalic cells, characteristic of viral cytopathic effects, were observed between 48 and 72 h post-infection. Furthermore, intranuclear acidophilic inclusion bodies (IBs) were identified in the inoculated primary culture cells, and the cytoplasm showed immunoreactivity with hyperimmune rabbit serum against OvHV-2. Moreover, in the liver histological sections from sick deer, immunoreactive juxtanuclear IBs were identified with the same rabbit hyperimmune serum. The obtained sequences were aligned with the OvHV-2 sequences reported in GenBank and revealed a nucleotide identity higher than 98%. Based on the evidence provided in this study, we conclude that the outbreak of SA-MCF in the municipality of Tequisquiapan in the state of Queretaro, Mexico, was caused by OvHV-2. This is the second study reporting that horses are susceptible to OvHV-2 infection and can develop SA-MCF. We identified for the first time in Mexico, the presence of OvHV-2 in buffy coats from horses and Artiodactyla.Copyright: © 2023 Madrigal-Valencia et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.