在新生猪小猪中不同亚基因型伪狂犬病病毒的致病性特征
1Key Laboratory of Animal Diseases and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.
Frontiers in veterinary science
|August 22, 2024
概括
与古典菌株相比,猪中伪狂犬病病毒变种菌株的病原性和复制性增加. 针对古典菌株的抗体对这些新兴变异菌株提供了较低的保护.
科学领域:
- 兽医病毒学 兽医病毒学
- 动物病理学 动物病理学
背景情况:
- 伪狂热病毒 (PRV) 在猪业中造成重大经济损失.
- 新出现的PRV变种株,特别是在中国,由于它们的传播和未知的致病性,引起了人们的担忧.
- 了解经典和变种PRV菌株之间的差异对于疾病控制至关重要.
研究的目的:
- 评估PRV亚型之间的复制特征和病毒性基因差异.
- 调查小猪中PRV菌株的临床特征,组织热带性和炎症反应.
- 评估抗体对抗经典和变种PRV菌株的交叉中和能力.
主要方法:
- 三种PRV菌株的隔离和表征.
- 在体外评估斑块大小和复制能力.
- 在体内小猪感染模型,以评估临床症状,死亡率,病毒分泌和组织热带性.
- 分析炎症反应和抗体中和试验.
主要成果:
- 基因型II变异的PRV菌株表现出比经典菌株更大的斑块大小和更高的复制率.
- 变种菌株导致较高的死亡率,严重的临床症状,增加的鼻脱落,以及更强烈的炎症反应.
- 在菌株之间观察到组织热带的差异.
- 对古典基因型II菌株的抗体显示出变种菌株的中和性减少,而对变种菌株的抗体有效中和了两种类型.
结论:
- 与古典菌株相比,基因型II变异的PRV菌株具有增强的致病性和复制性.
- 新兴的变种菌株对目前的伪狂犬病控制策略构成重大挑战.
- 抗体有效性是菌株特异性的,突出了针对PRV变种菌株的更新疫苗方法的需要.
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