This study aimed to determine the major diseases, antimicrobial use, and resistance in commensal Escherichia coli in dairy cattle in Jordan. Forty-three (large, n = 21; small, n = 22) farms were surveyed. A validated questionnaire was administered to the herdsmen to elicit information about disease prevalence, antimicrobial knowledge, and antimicrobial use. In addition, fecal samples were collected from 5 lactating animals on each farm. A total of 520 E. coli isolates were tested for resistance to 12 antimicrobials. From the herdsmen's perspective, the diseases that require use of veterinary services in large and small production systems were mastitis (51.2%), metritis (51.2%), and enteritis (39.5%), and the most commonly used antimicrobials were oxytetracycline and streptomycin. Dairy herdsmen (83.7%) reported that it is easy to purchase antimicrobials without a veterinary prescription and 97.7% of them more frequently changed the antimicrobial drug rather than increasing the dose when presented with nonresponse to treatment. Escherichia coli isolates exhibited high resistance to streptomycin (47.5%), tetracycline (45.4%), and ampicillin (34.2%). Less than 10% of isolates were resistant to chloramphenicol, kanamycin, gentamicin, ciprofloxacin, and ceftriaxone. Overall, 64.6 and 37.1% of the E. coli isolates exhibited resistance to ≥1 antimicrobial and multidrug resistance (resistance to ≥3 antimicrobial classes), respectively. The isolates exhibited 107 antimicrobial resistance profiles. This study indicates that antimicrobials are frequently misused in dairies in Jordan and that resistance among commensal E. coli toward antimicrobials of human and veterinary importance is high. Therefore, educational programs for herdsmen and enacting regulations and guidelines are necessary to promote the judicious use of antimicrobials in dairy animals in Jordan.

这项研究旨在确定约旦奶牛共病大肠杆菌中的主要疾病，抗菌药物使用和耐药性。对43个（大型，n = 21；小型，n = 22）农场进行了调查。向牧民发放经过验证的问卷，以获取有关疾病患病率，抗菌知识和抗菌剂使用的信息。另外，从每个农场的5只泌乳动物中收集粪便样品。总共520个大肠杆菌测试分离株对12种抗菌素的耐药性。从牧民的角度来看，在大型和小型生产系统中需要使用兽医服务的疾病是乳腺炎（51.2％），子宫炎（51.2％）和肠炎（39.5％），最常用的抗菌药物是土霉素和链霉素。奶牛牧民（83.7％）报告说，无需兽药处方就很容易购买抗菌药物，其中97.7％的人更经常更换抗菌药物，而不是对治疗无反应时增加剂量。大肠杆菌分离株表现出对链霉素（47.5％），四环素（45.4％）和氨苄青霉素（34.2％）的高抗性。不到10％的分离株对氯霉素，卡那霉素，庆大霉素，环丙沙星和头孢曲松耐药。总体上，分别有64.6％和37.1％的大肠杆菌分离株表现出对≥1抗菌和多药耐药（对≥3抗菌类别的耐药）。分离物表现出107种抗菌素耐药性。这项研究表明，抗菌药物在约旦的乳制品厂中经常被滥用，而普通大肠杆菌中的耐药性对人和兽用抗菌药物的重要性很高。因此，必须有针对牧民的教育计划并制定法规和指南，以促进在约旦乳牛动物中明智地使用抗菌药物。