Davies D H, Long D L, McCarthy A R, Herceg M
Vet Microbiol. 1986 Feb;11(1-2):125-44. doi: 10.1016/0378-1135(86)90013-1.
Groups of Caesarean-derived, colostrum-deprived lambs were inoculated by the intratracheal route with Pasteurella haemolytica 4 to 6 days after the inoculation of parainfluenza virus type 3 (PI3). Some were killed immediately (0 h) and others 24 h later. Control groups were inoculated with PI3 alone, P. haemolytica alone or media alone. Pulmonary phagocytic cells, P. haemolytica and PI3 were recovered by pulmonary lavage. The phagocytes were separated into alveolar macrophage (AM) and neutrophil fractions by density gradient centrifugation and examined biochemically and microbiologically. Twenty-four hours after the inoculation of P. haemolytica bacterial proliferation to greater than 0 h levels had occurred in four of six animals inoculated with P. haemolytica alone, two of eight inoculated with P. haemolytica 4 days after PI3 and all of eight inoculated with P. haemolytica 6 days after PI3. Mean bacterial numbers in animals inoculated with P. haemolytica 6 days after PI3 and killed at 24 h (10(9.1 +/- 1.9)) were significantly higher than they were in the other two groups killed at this time (PI3 4 days, P. haemolytica 24 h, mean = 10(5.3 +/- 1.7); P. haemolytica alone 24 h, mean = 10(4.5 +/- 2.9)). Pneumonic lesions were also more severe in the first group. This defect in pulmonary clearance and increase in the severity of pneumonia in animals inoculated with P. haemolytica 6 days after PI3 coincided with a 1000-fold decrease in virus titres in the lung between Day 6 and Day 7 after virus inoculation and the first detectable evidence of the host's immune response. The virus infection resulted in a significant increase in the number of AM that could be recovered from the lung and an increase in the number of AM with cytoplasmic vacuolation. However, there was no difference in the total number of AM or the number of vacuolated AM between animals that controlled the P. haemolytica infection and those in which proliferation of P. haemolytica occurred. The inoculation of P. haemolytica resulted in a 100-fold increase in the number of neutrophils in the lavage fluid, but there were no differences between virus-infected and uninfected animals, nor was there a difference between animals that controlled the P. haemolytica infection and those that did not.(ABSTRACT TRUNCATED AT 400 WORDS)
在接种3型副流感病毒（PI3）4至6天后，通过气管内途径给剖腹产出生且未摄入初乳的羔羊群体接种溶血巴氏杆菌。一些羔羊在接种后立即（0小时）处死，另一些在24小时后处死。对照组分别单独接种PI3、单独接种溶血巴氏杆菌或仅接种培养基。通过肺灌洗回收肺吞噬细胞、溶血巴氏杆菌和PI3。通过密度梯度离心将吞噬细胞分离为肺泡巨噬细胞（AM）和中性粒细胞组分，并进行生化和微生物学检查。接种溶血巴氏杆菌24小时后，单独接种溶血巴氏杆菌的6只动物中有4只、接种PI3 4天后接种溶血巴氏杆菌的8只动物中有2只，以及接种PI3 6天后接种溶血巴氏杆菌的所有8只动物，细菌增殖均超过0小时水平。接种PI3 6天后接种溶血巴氏杆菌并在24小时处死的动物（10（9.1±1.9））中的平均细菌数显著高于此时处死的其他两组（PI3 4天，溶血巴氏杆菌24小时，平均值=10（5.3±1.7）；单独接种溶血巴氏杆菌24小时，平均值=10（4.5±2.9））。第一组的肺部病变也更严重。在接种PI3 6天后接种溶血巴氏杆菌的动物中，肺部清除缺陷和肺炎严重程度增加与病毒接种后第6天至第7天肺中病毒滴度下降1000倍以及宿主免疫反应的首次可检测证据同时出现。病毒感染导致从肺中回收的AM数量显著增加，以及细胞质空泡化的AM数量增加。然而，在控制溶血巴氏杆菌感染的动物和溶血巴氏杆菌增殖的动物之间，AM总数或空泡化AM数量没有差异。接种溶血巴氏杆菌导致灌洗液中中性粒细胞数量增加100倍，但在病毒感染和未感染动物之间没有差异，在控制溶血巴氏杆菌感染的动物和未控制感染的动物之间也没有差异。（摘要截取自400字）
