Experimental models of porcine post-weaning colibacillosis and their relationship to post-weaning diarrhoea and digestive disorders as encountered in the field
Experimental models of porcine post-weaning colibacillosis and their relationship to post-weaning diarrhoea and digestive disorders as encountered in the field
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DOI：
10.1016/s0378-1135(99)00202-3
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发表时间：
2000-03-15
影响因子：
3.3
通讯作者：
Jestin, A
中科院分区：
文献类型：
--
作者：
Madec, F;Bridoux, N;Jestin, A
本研究的目的是建立一个可靠的猪断奶后大肠杆菌病的模型系统，并在这样做，以评估肠道致病性大肠杆菌断奶后腹泻和消化系统疾病的主要关系，在该领域遇到的。采用168头28日龄断奶的SPF仔猪进行了6个连续试验。将仔猪分为23个处理组，其中17个处理组经口或灌胃接种大肠杆菌。大肠杆菌（LT+、STI+、STII+），具有K88（F4）等粘附因子。仔猪被激发一次，（断奶后第4天）或断奶后数天接种，每次接种的攻毒负荷为10（8）至10（12）CFU。总体而言，14.5%的接种猪出现严重疾病并死亡：这些猪的消化道出现典型的大肠杆菌病病变，50%的接种猪至少在1天内出现腹泻，但是是短暂的（平均1.7天），在攻击后很快出现（有时在半天内），并伴有抑郁和低体重增加的迹象。一般来说，迅速恢复，然后发生。在接种后的第二个2周，大多数接种组的猪的日增重达到与未接种对照组相同的水平。只有少数猪发生持续数天的慢性肠炎，这是田间病例中通常观察到的情况。腹泻在对K88菌毛受体检测为粘附阳性的仔猪中更常见，但这些动物中的疾病并不更严重。所有猪的反应主要取决于所用接种物，尤其是攻毒负荷。虽然肠毒素E.大肠杆菌在断奶后腹泻的病因学中显然是重要的，其他因素也是产生断奶后腹泻所必需的：慢性断奶后消化障碍和商业养猪场中常见的不节俭。(C)2000 Elsevier Science B.V.保留所有权利。
The aim of this study was to develop a reliable model system of porcine post-weaning colibacillosis, and in doing so to assess the primary relationship of enterotoxigenic Escherichia coli to post-weaning diarrhoea and digestive disorders as encountered in the field. Six sequential experiments were carried out using 168 SPF piglets weaned into an optimal controlled environment at 28 days of age. The piglets were allocated to 23 treatment groups, 17 of which were inoculated either orally or intragastrically with enterotoxigenic strains of E. coli (LT+, STI+, STII+) possessing adhesive factors including K88 (F4). The piglets were challenged either once (Day 4 post-weaning) or on several days post-weaning, with the challenge load for each inoculation varying from 10(8) to 10(12) CFU.Overall 14.5% of inoculated pigs developed severe illness and died: these had lesions in their digestive tracts typical of colibacillosis, Diarrhoea occurred on at least 1 day in 50% of inoculated pigs, but was transient (1.7 days on average), appeared very soon after challenge (sometimes within half a day), and was accompanied by signs of depression and low weight gain. Generally a prompt recovery then occurred. In the second 2 weeks post-inoculation daily weight gain reached the same level in most inoculated groups of pigs as in the uninoculated controls. Only a small number of pigs developed a chronic enteritis lasting several days, as is typically observed in field cases. Diarrhoea was more common in the piglets that were tested adhesive positive to the K88 fimbriae receptor, but the disorders were no more severe in these animals. The response of all pigs depended primarily on the inoculum used, and especially on the challenge load. Although enterotoxigenic E. coli are clearly important in the aetiology of post-weaning diarrhoea, other factors are also required for the production of the: chronic post-weaning digestive disorders and ill-thrift that are commonly encountered in commercial piggeries. (C) 2000 Elsevier Science B.V. All rights reserved.