Kamel Mohammed, Abo El-Hassan Diea G, El-Sayed Amr
Faculty of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany.
Trop Anim Health Prod. 2015 Aug;47(6):1161-7. doi: 10.1007/s11250-015-0843-2. Epub 2015 May 7.
In the present work, the epidemiological role of apparently healthy sheep in transmission of Escherichia coli O157:H7 in different seasons was investigated. Fecal samples (convenience sampling) of apparently healthy farmed sheep (three farms, n = 70) and from 15 wandering flocks fed on city wastes (n = 80) in the Giza governorate were examined. The samples were collected in spring under mild weather conditions and during hot summer to be compared. Out of the 150 animals, 13 (8.7%) were E. coli O157 shedders. The 13 ovine sorbitol-negative E. coli O157 were characterized by different PCR sets. The eae gene was detected in 11 isolate (85%), stx1 in 3 isolates (23%), stx2 in 8 isolates (62%), and finally the hlyA in 11 isolate (85%). Among the 13 isolates, 2 strains (15%) were positive for eae, stx1, stx2, and hlyA as gene combination, one isolate (8%) for eae, stx1, and hlyA, 5 isolates (38%) for eae, stx2, and hlyA, 1 isolate (8%) for eae and stx2, 2 isolates (15%) contained eae and hlyA, 1 isolate (8%) contained hlyA only, and finally, 1 isolate (8%) did not contain any of these genes. None of the isolates showed the gene combination eae stx1, stx1 hlyA, or stx2 hlyA. The results indicated significant association of unfavorable weather and management conditions on O157:H7 shedding while the age or sex did not play any role in this process.
在本研究中，调查了看似健康的绵羊在不同季节传播大肠杆菌O157:H7中的流行病学作用。对吉萨省三个养殖场看似健康的养殖绵羊（n = 70）和以城市垃圾为食的15个流浪羊群（n = 80）的粪便样本（方便抽样）进行了检测。样本在春季温和天气条件下以及炎热的夏季采集，以便进行比较。在150只动物中，13只（8.7%）为大肠杆菌O157排泄者。13株绵羊山梨醇阴性大肠杆菌O157通过不同的PCR组进行了特征分析。在11株分离株（85%）中检测到eae基因，3株分离株（23%）中检测到stx1，8株分离株（62%）中检测到stx2，最后在11株分离株（85%）中检测到hlyA。在13株分离株中，2株（15%）作为基因组合，eae、stx1、stx2和hlyA呈阳性，1株分离株（8%）eae、stx1和hlyA呈阳性，5株分离株（38%）eae、stx2和hlyA呈阳性，1株分离株（8%）eae和stx2呈阳性，2株分离株（15%）含有eae和hlyA，1株分离株（8%）仅含有hlyA，最后，1株分离株（8%）不含有这些基因中的任何一种。没有分离株显示出eae stx1、stx1 hlyA或stx2 hlyA的基因组合。结果表明，不利的天气和管理条件与O157:H7排泄显著相关，而年龄或性别在此过程中不起任何作用。
