血清4型禽腺病毒强毒株GY株的分离鉴定和致病性研究

Isolation, Identification and Pathogenicity Study of GY strain of Serotype 4 Fowl Adenovirus

关键词:  禽腺病毒  分离  鉴定  致病性

Key words:  Fowl adenovirus, Isolation, Identification, Pathogenesis

摘要:

禽腺病毒是近年来危害我国养禽业的垂直传播性病毒之一，疫苗是目前防控该病的主要途径，而标准化检验强毒株在疫苗研制过程中必不可少。本研究从山东某疑似感染禽腺病毒的发病鸡群中采集病料并分离到一株4型禽腺病毒GY株，经克隆纯化后用LMH细胞繁殖的病毒滴度可以达到107.5TCID50/0.1ml，且纯净性良好。动物回归试验结果表明，攻毒鸡8/10死亡，剖检均出现心包积液，肝脏肿大、出血或坏死，可作为检验用强毒。从攻毒途径、攻毒剂量等方面对I群禽腺病毒（4型）GY株对SPF鸡的致病性进行了研究。结果显示，经胸部肌肉注射后发病率和发病时间相对颈部皮下注射途径更有优势，确定将攻毒途径定为肌肉注射。通过比较不同剂量（5×103.0~5×106.0TCID50）GY株病毒攻击SPF鸡致病性，将攻毒剂量定为5×105.0 TCID50。上述研究结果为确定I群禽腺病毒（4型）GY株作为检验用毒的攻毒途径、剂量和发病标准提供了依据。

Abstract:

Fowl Adenoviruses (FAdV) are one of the most prevalent vertically transmitted viruses diseases caused by these viruses. It is important to the identify high virulent stains of these viruses in order to develop effective vaccines. In this study, strain GY of serotype 4 fowl adenovirus was isolated from a diseased chicken flock in Shandong. Virulent test on purified clone of GY strain, propagated on LMH cells, showed high virus titer, reaching 107.5TCID50/0.1ml. Tests on SPF chickens showed high pathogenicity, mortality reaching 80%, pathological dissection result showed pericardial effusion, liver enlargement, bleeding and necrosis. Different dosages and routes of infections were tested , showing chest intramuscular injection to be the most effective route of infection, and 5×105.0 TCID50 to be the optimum dosage of infection. This study demonstrates that the GY strain is high virulent and is promising to be adopted as reference strain for inspection of serotype 4 fowl adenovirus, and provides evidence-based guidance for future applications.