Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, Jilin Province, China.
Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, Changchun, Jilin Province, China.
BMC Vet Res. 2024 Nov 29;20(1):539. doi: 10.1186/s12917-024-04400-5.
At the end of 2021, an epidemic of reproductive abnormalities in cows occurred in Jilin Province, China, posing an urgent need for a rapid diagnosis.
To identify the cause of the disease, a total of 172 samples were collected from 21 dead calves and 45 aborting or pregnant cows in 10 farms across the province. Routine PCR or RT-PCR detection did not find any common abortion-related agents. We then employed the viromics-based precision diagnosis method to analyze these samples, and the read-based annotation showed signals of an Akabane disease virus (AKAV) in some libraries. To further identify the virus, nested RT-PCR detection revealed that 52.3% (11/21) of dead calves and 26.6% (12/45) of cows were positive for the virus. Phylogenetic analysis of the partial fragments showed that the S segment of the virus was 100% identical to the Chinese strain TJ2016, but its M and L segments shared 94.3% and 96.5% identities with an Israeli strain.
The viromic and molecular results suggested that these animals were infected with a reassortant AKAV. Coupled with the clinical signs, the virus should be responsible for the epizootic, highlighting that molecular and serological surveys of the virus in cows during early pregnancy, as well as ecological investigation in its arthropod vectors, are necessary.
2021 年末，中国吉林省发生了一起奶牛生殖异常疫情，急需快速诊断。
为了查明病因，从全省 10 个农场的 21 头病死犊牛和 45 头流产或妊娠奶牛中采集了 172 份样本。常规 PCR 或 RT-PCR 检测未发现任何常见的流产相关病原体。随后，我们采用基于病毒组学的精准诊断方法对这些样本进行分析，基于读段的注释在一些文库中显示出了阿卡斑病毒（AKAV）的信号。为了进一步鉴定该病毒，巢式 RT-PCR 检测显示，52.3%（11/21）的病死犊牛和 26.6%（12/45）的奶牛病毒检测呈阳性。病毒部分片段的系统发育分析表明，该病毒的 S 片段与中国 2016 年 TJ 株完全一致，但 M 和 L 片段与以色列株的同源性分别为 94.3%和 96.5%。
病毒组学和分子结果提示这些动物感染了重组 AKAV。结合临床症状，该病毒应为此次疫情的病原，这突显了在奶牛妊娠早期对该病毒进行分子和血清学调查以及对其节肢动物媒介进行生态调查的必要性。
