Martin Michael P, Wakenell P S, Woolcock P, O'Connor B
University of California at Davis, School of Veterinary Medicine, Department of Population Health and Reproduction, 1 Shields Avenue, 1114 Tupper Hall, Davis, CA 95616, USA.
Avian Dis. 2007 Jun;51(2):584-9. doi: 10.1637/0005-2086(2007)51[584:EOTEOT]2.0.CO;2.
Infectious bronchitis virus CA99 serotype was isolated from several broiler flocks in Northern California. The virus caused late-onset respiratory disease and increased airsacculitis condemnation in affected flocks despite the use of an established infectious bronchitis virus vaccination program. An experimental study compared Holland/Arkansas and Massachusetts/Arkansas vaccination protocols to determine the efficacy of commercial infectious bronchitis virus vaccines in reducing respiratory disease and airsacculitis lesions found at processing that were associated with a CA99 field isolate. All vaccination groups were given Massachusetts/Connecticut strains of infectious bronchitis virus vaccines at age 1 day followed by vaccination with either Holland/ Arkansas or Massachusetts/Arkansas vaccine strains at 18 days of age. Birds were challenged at age 31 days with a CA99 field isolate. Gross pathology, histopathology, and virus isolation were evaluated. Chickens vaccinated with Holland/Arkansas had marginally better protection against CA99 challenge than chickens vaccinated with Massachusetts/Arkansas, although differences were not statistically significant.
传染性支气管炎病毒CA99血清型是从加利福尼亚州北部的几个肉鸡群中分离出来的。尽管使用了既定的传染性支气管炎病毒疫苗接种程序，但该病毒仍在受影响的鸡群中引发了迟发性呼吸道疾病，并增加了气囊炎的判废率。一项实验研究比较了荷兰/阿肯色州和马萨诸塞州/阿肯色州的疫苗接种方案，以确定商业传染性支气管炎病毒疫苗在减少加工时发现的与CA99田间分离株相关的呼吸道疾病和气囊肿病变方面的效果。所有接种组在1日龄时接种马萨诸塞州/康涅狄格州株的传染性支气管炎病毒疫苗，然后在18日龄时接种荷兰/阿肯色州或马萨诸塞州/阿肯色州疫苗株。在31日龄时用CA99田间分离株对鸡进行攻毒。评估大体病理学、组织病理学和病毒分离情况。接种荷兰/阿肯色州疫苗的鸡对CA99攻毒的保护作用略优于接种马萨诸塞州/阿肯色州疫苗的鸡，尽管差异无统计学意义。
