Porter J F, Connor K, Krueger N, Hodgson J C, Donachie W
Moredun Research Institute, Edinburgh, UK.
J Comp Pathol. 1995 May;112(4):381-9. doi: 10.1016/s0021-9975(05)80019-2.
Three groups of specific pathogen-free (SPF) lambs were inoculated intratracheally with an ovine isolate of Bordetella parapertussis (5.5 x 10(9) colony-forming units) or with B. parapertussis followed 2 or 5 days later with Pasteurella haemolytica serotype A2 (120-180 million colony-forming units). When P. haemolytica A2 was administered 2 days after infection with B. parapertussis all lambs became febrile for at least 72 h. At necropsy their lungs were discoloured, congested and showed large areas of collapse and consolidation which, in one case, covered the entire lung. Histopathological examination confirmed that the combined infection produced a severe acute bronchopneumonia in four of seven lambs. B. parapertussis and P. haemolytica were recovered from all of the lambs in this group. Seven lambs challenged with P. haemolytica 5 days after B. parapertussis and six lambs infected with B. parapertussis alone showed no clinical signs of disease other than mild pyrexia and only mild histopathological changes. B. parapertussis, but not P. haemolytica, was recovered from these lambs. The findings indicated that B. parapertussis predisposed the SPF lambs to P. haemolytica pneumonia. This effect appeared to be dependent upon the time interval between the administration of the two agents.
将三组无特定病原体（SPF）羔羊经气管内接种绵羊百日咳博德特氏菌分离株（5.5×10⁹菌落形成单位），或先接种百日咳博德特氏菌，然后在2天或5天后接种溶血巴斯德氏菌A2型（1.2亿至1.8亿菌落形成单位）。当在感染百日咳博德特氏菌2天后给予溶血巴斯德氏菌A2型时，所有羔羊至少发热72小时。尸检时，它们的肺变色、充血，出现大面积萎陷和实变，在1例中，整个肺都被累及。组织病理学检查证实，联合感染在7只羔羊中的4只中引起了严重的急性支气管肺炎。在该组的所有羔羊中均分离到百日咳博德特氏菌和溶血巴斯德氏菌。7只在感染百日咳博德特氏菌5天后受到溶血巴斯德氏菌攻击的羔羊以及6只仅感染百日咳博德特氏菌的羔羊，除了轻度发热外没有其他疾病临床症状，仅表现出轻微的组织病理学变化。从这些羔羊中分离到了百日咳博德特氏菌，但未分离到溶血巴斯德氏菌。这些发现表明，百日咳博德特氏菌使SPF羔羊易患溶血巴斯德氏菌肺炎。这种作用似乎取决于两种病原体给药之间的时间间隔
