Joens L A, Nibbelink S, Glock R D
Department of Veterinary Science, University of Arizona, Tucson 85721, USA.
Am J Vet Res. 1997 Oct;58(10):1125-31.
To evaluate experimental induction of porcine proliferative enteritis (PPE), using cell cultured Lawsonia intracellularis (ileal symbiont intracellularis), and to determine whether dexamethasone administration or age of the host or both affects susceptibility to L intracellularis infection.
Thirty-two 3- or 7-week-old pigs.
Lawsonia intracellularis was extracted from tissue with lesions of PPE and was subcultured in a continuous Henle 407 cell line at 37 C under an atmosphere of 5% CO2. Three- or 7-week-old pigs were inoculated orally with 100 ml of a 10-day-old cell culture preparation of the bacterium or infective intestinal homogenates. Control pigs were inoculated with uninfected Henle cells. Pigs were observed daily for clinical signs of infection and necropsied at death or at termination of the study. Lesions in the small and large intestines were recorded.
Diarrhea was observed in pigs 4 to 7 days after inoculation with the pure culture agent or homogenates and lasted throughout the study period. Histologic lesions consistent with PPE were detected in pigs inoculated with pure culture. Intestinal lesions were absent in control pigs inoculated with uninfected Henle cells. Differences in lesions were not significant between treatment groups that varied in age or were receiving dexamethasone. Tissue specimens from pigs at necropsy were culture negative for Salmonella spp and Serpulina hyodysenteriae.
Gross and microscopic lesions typical of acute PPE were induced in pigs by use of a cell culture agent. Age differences and the stress induced by administration of dexamethasone had no effect on development of intestinal lesions.
使用细胞培养的胞内劳森菌（回肠共生胞内菌）评估猪增生性肠炎（PPE）的实验性诱导，并确定给予地塞米松或宿主年龄或两者是否会影响对胞内劳森菌感染的易感性。
32头3周龄或7周龄仔猪。
从患有PPE病变的组织中提取胞内劳森菌，并在37℃、5%二氧化碳气氛下于连续的亨勒407细胞系中传代培养。给3周龄或7周龄仔猪口服接种100 ml该细菌的10日龄细胞培养制剂或感染性肠道匀浆。对照仔猪接种未感染的亨勒细胞。每天观察仔猪是否有感染的临床症状，并在死亡时或研究结束时进行剖检。记录小肠和大肠的病变情况。
接种纯培养物制剂或匀浆后4至7天，仔猪出现腹泻，并持续整个研究期间。接种纯培养物的仔猪检测到与PPE一致的组织学病变。接种未感染亨勒细胞的对照仔猪未出现肠道病变。年龄不同或接受地塞米松治疗的治疗组之间病变差异不显著。剖检仔猪的组织标本沙门氏菌属和猪痢疾蛇形螺旋体培养均为阴性。
使用细胞培养制剂在仔猪中诱导出了急性PPE典型的大体和微观病变。年龄差异和给予地塞米松引起的应激对肠道病变的发展没有影响。
