Liu Yongbo, Fu Cheng, Lu Gang, Luo Jie, Ye Shaotang, Ou Jiajun, Wang Xiangbin, Xu Haibin, Huang Ji, Wu Liyan, Zhang Xin, Wu Peixin, Li Shoujun
College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.
Guangdong Provincial Key Laboratory of Prevention and Control for Severe Clinical Animal Diseases, Guangzhou, China.
Front Vet Sci. 2020 Nov 13;7:580301. doi: 10.3389/fvets.2020.580301. eCollection 2020.
The canine influenza virus (CIV) outbreaks have raised concerns as they pose a threat to the health of dogs. The successful construction of a canine influenza (CI) infection model is essential to study the CIV. Here we investigated the pathogenicity of different infectious doses of H3N2 CIV in Beagle dogs. Thirty-seven healthy Beagle dogs were used in the experiment and were infected with 10, 10, 10, and 10 50% egg-infectious doses (EID). Compared to the dogs in the other three groups, those in the 10 EID group presented with obvious clinical symptoms, high virus titer, and typical pathological changes. Considering the ensemble of clinical scores, body temperature, virus shedding, lung lesions, pathological section scores, and visceral virus titers, we determined that 10 EID is the minimum infectious dose for the Beagle infection model. The other three infectious doses had almost no clinical symptoms. These results indicate that 10 EID is the minimum infectious dose of H3N2 CIV that can cause obvious clinical manifestations and pathological changes associated with CI in Beagle dogs. The theoretical framework developed in this research will guide the establishment of an infection model of CIV for future research.
犬流感病毒（CIV）的爆发引发了人们的担忧，因为它们对犬类健康构成威胁。成功构建犬流感（CI）感染模型对于研究CIV至关重要。在此，我们研究了不同感染剂量的H3N2 CIV对比格犬的致病性。实验使用了37只健康的比格犬，分别用10、10、10和10个50%鸡胚感染剂量（EID）进行感染。与其他三组犬相比，10 EID组的犬表现出明显的临床症状、高病毒滴度和典型的病理变化。综合临床评分、体温、病毒排出、肺部病变、病理切片评分和内脏病毒滴度，我们确定10 EID是比格犬感染模型的最小感染剂量。其他三个感染剂量几乎没有临床症状。这些结果表明，10 EID是能在比格犬中引起与CI相关的明显临床表现和病理变化的H3N2 CIV的最小感染剂量。本研究建立的理论框架将指导未来研究中CIV感染模型的建立。
