Ikeda S, Matsuda K, Yonaiyama K
Natl Inst Anim Health Q (Tokyo). 1976 Spring;16(1):1-7.
The VR strain of avian encephalomyelitis virus, which had been adapted to embryonated hen's eggs, was inoculated into 2-day-old chicks by the subcutaneous route (10(2.5) approximately 10(3.0) EID50) or by the oral route (10(4.8) EID50). The chicks were examined chronologically for the distribution of the virus in the body. As a result, minute amounts of the virus were detected from the liver, spleen, pancreas, and muscle at the site of inoculation one day after inoculation and various amounts from almost all the organs 3 days and more after inoculation. The virus titer could nearly reach a maximum 7 to 9 days after inoculation. Above all, such high virus titers as ranging from 10(4.3) to 10(5.8) EID50/0.1 g were demonstrated in the brain, heart, liver, spleen, and pancreas. After that, there was a tendency for virus titer to decrease in most organs and for virus to multiply persistently in the pancreas, brain, and eyeball. Virus titer was maintained at a level of 10(2.3) approximately 10(2.8) EID50/0.1 g in these three organs even 21 days after inoculation. In the group of subcutaneous inoculation, all the chicks manifested clinical signs of infection 5 to 10 days after inoculation. On the other hand, no chicks were involved in clinical infection in the group of oral inoculation. Multiplication of the virus was delayed in the body of these chicks. Small amounts of the virus were detected from the spleen and pancreas 11 days after inoculation. Low titers (10(2.7) EID50/0.1 g at the highest) of the virus were only detected from the brain, spinal cord, spleen, pancreas, esophagus, and other organs 14 and 21 days after inoculation.
将适应鸡胚的禽脑脊髓炎病毒VR株通过皮下途径（10(2.5) 约10(3.0) EID50）或口服途径（10(4.8) EID50）接种到2日龄雏鸡体内。按时间顺序检查雏鸡体内病毒的分布情况。结果，接种后1天在接种部位的肝脏、脾脏、胰腺和肌肉中检测到微量病毒，接种3天及更久后在几乎所有器官中检测到不同量的病毒。病毒滴度在接种后7至9天几乎可达到最高值。最重要的是，在脑、心脏、肝脏、脾脏和胰腺中显示出10(4.3) 至10(5.8) EID50/0.1 g的高病毒滴度。此后，大多数器官中的病毒滴度有下降趋势，而病毒在胰腺、脑和眼球中持续增殖。即使在接种后21天，这三个器官中的病毒滴度仍维持在10(2.3) 约10(2.8) EID50/0.1 g的水平。在皮下接种组中，所有雏鸡在接种后5至10天出现感染的临床症状。另一方面，口服接种组中没有雏鸡发生临床感染。这些雏鸡体内病毒的增殖延迟。接种后11天在脾脏和胰腺中检测到少量病毒。接种后14天和21天，仅在脑、脊髓、脾脏、胰腺、食管和其他器官中检测到低滴度（最高为10(2.7) EID50/0.1 g）的病毒。
