摘要
【背景】禽滑液囊支原体是感染鸡的一种重要病原体,给我国的家禽养殖业带来了严重的经济损失。【目的】评价从病鸡中分离到的3株禽滑液囊支原体的致病性,以期丰富不同区域来源的分离株对鸡致病性的认识。【方法】分别用分离株CHN-WF224-2016、CHN-BZJ2-2015、CHN-JNB19-2016感染商品肉鸡,并在攻毒后第10天和21天进行实验室解剖,通过气囊和足垫的临床病变、血清学检测结果及气管粘膜病理形态学改变来比较评价分离株的致病力。【结果】CHN-BZJ2-2015和CHN-WF224-2016分离株能引起明显足垫肿胀和关节滑膜炎,其中CHN-BZJ2-2015分离株致病力最强,感染21d后的血清学检测和气管粘膜厚度与CHN-JNB19-2016分离株和MS-H疫苗株比较差异显著(P<0.05)。【结论】本研究表明我国目前流行的禽滑液囊支原体菌株其致病力存在明显差异,强调养殖场要积极控制和预防禽滑液囊支原体感染的重要性,同时为今后该疫苗的研发积累了实验数据。
[Background] Mycoplasma synoviae(MS) is an important causative agent infecting chicken, which causes enormous losses to the poultry industry in China. [Objective] This study was designed to evaluate the pathogenicity of three isolates from MS outbreak farms, which could enrich our understanding about pathogenicity of MS isolates from different districts. [Methods] Systemic MS infection was induced experimentally in commercial broiler chickens with recent MS isolates(CHN-WF224-2016, CHN-BZJ2-2015 and CHN-JNB19-2016). The virulence of each strain was evaluated by detecting air sac and foot pad lesions, serologic response, tracheal mucosal thickness and MS isolation rates from the infected chicken at 10 and 21 days post-infection and comparing these results with those obtained from a live attenuated vaccine strain(MS-H) and uninfected controls. [Results] Isolates CHN-BZJ2-2015 and CHN-WF224-2016 induced foot pad lesions and typical infectious synovitis, especially CHN-BZJ2-2015 group. Serologic response and tracheal mucosal thickness measurements at 21 days post infection indicated that CHN-BZJ2-2015 isolate was significantly more virulent than the CHN-JNB19-2016 isolate and MS-H strain(P<0.05). [Conclusion] The variation in virulence of MS isolates emphasizes the importance of active, on-going control and prevention of MS in the chicken flocks of China and accumulates experimental data for vaccine development.
引文
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