Cawthraw S A, Wassenaar T M, Ayling R, Newell D G
Applied and Molecular Immunology Unit, Central Veterinary Laboratory (Weybridge), Addlestone, Surrey, UK.
Epidemiol Infect. 1996 Aug;117(1):213-5. doi: 10.1017/s0950268800001333.
The mechanisms by which Campylobacter jejuni rapidly spreads through large broiler flocks are unknown. Recent evidence suggests that the minimum infective oral dose for 100% caecal colonization is about 10(4) cfu, which, with such a 'fragile' organism, may limit transmissibility. However, the colonization potential of laboratory-adapted strains may be anomalous compared with fresh isolates or those passaged in vivo. The colonization potential of two chicken and one human C. jejuni isolates, which were minimally passaged, have been investigated using a quantitative model of chicken colonization. There was no detectable difference between these strains but all were more efficient colonizers than a laboratory-adapted strain 81116. In addition, the colonization potential of C. jejuni strain 81116 following a passage in vivo was also determined. The results indicated this increased c. 10000 fold following a single passage in vivo, such that a dose of only 40 cfu caused maximal colonization. Enhanced colonization potential may, therefore, account for the rapid rate of transmission within large flocks.
空肠弯曲菌在大型肉鸡群中迅速传播的机制尚不清楚。最近的证据表明，实现100%盲肠定植的最低感染口服剂量约为10⁴cfu，对于这样一种“脆弱”的生物体而言，这可能会限制其传播能力。然而，与新鲜分离株或体内传代的菌株相比，实验室适应菌株的定植潜力可能有所不同。使用鸡定植定量模型研究了两种鸡源和一种人源的空肠弯曲菌分离株（传代次数极少）的定植潜力。这些菌株之间没有可检测到的差异，但它们都是比实验室适应菌株81116更有效的定植菌。此外，还测定了空肠弯曲菌菌株81116在体内传代后的定植潜力。结果表明，在体内单次传代后，其定植潜力增加了约10000倍，以至于仅40 cfu的剂量就能导致最大程度的定植。因此，增强的定植潜力可能解释了在大型鸡群中快速传播的速度。
