This study set out to identify the presence of bovine immunodeficiency virus (BIV) in animals geographically located in Mexico. BIV was first discovered in the United States in a dairy cow with persistent lymphocytosis, lymphoid hyperplasia and lymphocytic encephalitis. Many studies indicate that BIV infection is globally distributed, but its presence in Mexico remains unknown. We collected 1,168 heparinized blood samples from cattle in ten states across the Mexican Republic, then separated plasma using centrifugation and tested for antibodies against BIV. We used an indirect ELISA based on the use of a synthetic peptide derived from transmembrane glycoprotein (gp45/TM). In order to identify the viral genome, we designed a synthetic gene as a PCR control, as well as a pair of oligonucleotides for amplifying a 519 bp product of the env gene which encodes the surface protein. Positive amplicons were purified and subjected to nucleotide sequencing. A total of 189 (28.94%) tested plasma samples suggest the presence of specific anti‐BIV antibodies in all states studied except for Chiapas. Additionally, PCR results identified six positive cows in the states of Puebla and Coahuila. BIV in these cows was confirmed via nucleotide sequencing and in silico analysis of these samples. This is the first report of the presence of BIV in Mexican cattle.

中文翻译：

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墨西哥牛感染牛免疫缺陷病毒的第一个证据。

本研究旨在确定位于墨西哥的动物体内是否存在牛免疫缺陷病毒（BIV）。BIV 最初是在美国在一头患有持续性淋巴细胞增多、淋巴样增生和淋巴细胞性脑炎的奶牛身上发现的。许多研究表明，BIV 感染在全球范围内分布，但墨西哥是否存在该感染仍不清楚。我们从墨西哥共和国十个州的牛身上采集了 1,168 份肝素化血液样本，然后通过离心分离血浆并测试 BIV 抗体。我们使用基于跨膜糖蛋白 (gp45/TM) 衍生的合成肽的间接 ELISA。为了鉴定病毒基因组，我们设计了一个合成基因作为 PCR 对照，以及一对用于扩增编码表面蛋白的env基因的 519 bp 产物的寡核苷酸。纯化阳性扩增子并进行核苷酸测序。总共 189 份 (28.94%) 测试血浆样本表明，除恰帕斯州外，所有研究的州都存在特异性抗 BIV 抗体。此外，PCR 结果在普埃布拉州和科阿韦拉州发现了六头阳性奶牛。通过核苷酸测序和这些样本的计算机分析证实了这些奶牛的 BIV。这是墨西哥牛中存在 BIV 的第一份报告。