Toker Eda Baldan, Ates Ozer, Aytoğu Gizem, Yaşar Mevlüt, Aybey Nilay, Yeşilbağ Kadir
Department of Virology, Faculty of Veterinary Medicine, Bursa Uludag University, Bursa, Türkiye.
Department of Virology, Faculty of Veterinary Medicine, Afyon Kocatepe University, Afyonkarahisar, Türkiye.
Microb Pathog. 2025 Oct;207:107869. doi: 10.1016/j.micpath.2025.107869. Epub 2025 Jul 3.
The Bovine gammaherpesvirus type 4 (BoHV-4) has been detected worldwide in healthy and disease-exhibiting cattle. Notably, BoHV-4 has recently been identified in bovine respiratory system infections. This study focuses on the isolation and complete genome characterization of Bovine gammaherpesvirus-4 (BoHV-4) as a primary viral agent responsible for respiratory infections in cattle. Cytopathogenic effects were observed in MDBK cells, confirming the presence of an enveloped DNA virus in identification tests. The viral titer of isolate BoHV-4/9746 at the 7th passage level was 6.75 log TCID/0.1 mL. PCR tests (TK gene) identified BoHV-4 as the only viral agent present, ruling out other common respiratory (BCoV, BoHV-1, BVDV, BRSV, BPIV-3, IDV, and BEV) applied to the 5th passage supernatant. WGS analysis revealed a partial LUR sequence (86870 bp) of the BoHV-4 /9746 Bursa-TR isolate, which showed high similarity (99.8%) to the reference V.test strain. The results of phylogenetic analyses applied according to partial LUR and TK gene regions also support each other, and BoHV-4 BoHV-4/9746 isolate branches among Genotype-1 sequences, similar to other European BoHV-4 strains. Cross-neutralization antibody reactions put forth a four-fold decrease in the neutralizing capacity of the BoHV-1 hyperimmune sera against the isolate BoHV-4 /9746. In conclusion, negative results of lung sample for other viral agents affecting the respiratory tract suggest that BoHV-4 may act as a primary viral agent. This study is the first report of a partial LUR genome of a Turkish BoHV-4 isolated from the respiratory tract.
牛4型γ疱疹病毒（BoHV-4）已在全球范围内的健康牛和患病牛中被检测到。值得注意的是，BoHV-4最近在牛呼吸系统感染中被发现。本研究聚焦于牛γ疱疹病毒4型（BoHV-4）的分离及全基因组特征分析，该病毒是牛呼吸道感染的主要致病病毒。在MDBK细胞中观察到细胞病变效应，在鉴定试验中证实存在一种包膜DNA病毒。分离株BoHV-4/9746在第7代传代水平的病毒滴度为6.75 log TCID/0.1 mL。PCR检测（TK基因）确定BoHV-4是唯一存在的病毒病原体，排除了应用于第5代传代上清液的其他常见呼吸道病毒（牛冠状病毒、牛疱疹病毒1型、牛病毒性腹泻病毒、牛呼吸道合胞体病毒、牛副流感病毒3型、异源型犬瘟热病毒和牛肠道病毒）。全基因组测序分析揭示了BoHV-4 /9746法氏囊TR分离株的部分LUR序列（86870 bp），其与参考V.test株具有高度相似性（99.8%）。根据部分LUR和TK基因区域进行的系统发育分析结果也相互支持，BoHV-4 BoHV-4/9746分离株在1型基因型序列中分支，与其他欧洲BoHV-4毒株相似。交叉中和抗体反应显示，BoHV-1超免疫血清对分离株BoHV-4 /9746的中和能力下降了四倍。总之，影响呼吸道的其他病毒病原体的肺样本检测结果为阴性，表明BoHV-4可能是主要致病病毒。本研究是关于从呼吸道分离出的土耳其BoHV-4部分LUR基因组的首次报道。
