Leitner G, Heller E D
Department of Animal Science, Hebrew University of Jerusalem, Faculty of Agriculture, Rehovot, Israel.
Avian Dis. 1992 Apr-Jun;36(2):211-20.
In order to investigate the possibility of pathogenic Escherichia coli penetrating the bloodstream via the intestinal mucosa in normal and stressed turkeys and chickens, birds were inoculated orally with the bacteria or exposed environmentally to it. Immediately after hatch, intestines contained a substantial number of coliform bacteria that increased with time. In orally infected turkeys, the pathogenic bacteria (nalidixic-acid-resistant O78) replaced 10%-50% of the native coliform flora but could not be isolated from the trachea or blood. Environmentally exposed groups exhibited pathogenic bacteria in intestines but not in blood. Stressing of exposed turkeys resulted in isolation of the pathogenic bacteria from blood and even spleen. In orally infected broiler chickens, stress resulted in bacteremia and mortality. Chickens that were exposed to pathogenic bacteria at a young age and showed no mortality or morbidity demonstrated no detrimental effects due to challenge with the same pathogenic bacteria later in life. Stress seems to cause penetration of the pathogenic bacteria into the bloodstream, which in turn can cause severe disease and mortality.
为了研究致病性大肠杆菌在正常和应激状态下的火鸡和鸡中通过肠黏膜进入血液循环的可能性，给禽类口服接种该细菌或使其环境暴露于该细菌。刚孵化后，肠道中含有大量大肠菌群细菌，且其数量随时间增加。在口服感染的火鸡中，病原菌（耐萘啶酸的O78）取代了10%-50%的原生大肠菌群，但在气管或血液中未分离到该病原菌。环境暴露组在肠道中检出了病原菌，但血液中未检出。对暴露的火鸡施加应激导致从血液甚至脾脏中分离出病原菌。在口服感染的肉鸡中，应激导致菌血症和死亡。幼年时暴露于病原菌且未出现死亡或发病的鸡，在生命后期再次受到相同病原菌攻击时未表现出有害影响。应激似乎会导致病原菌进入血液循环，进而引发严重疾病和死亡。
