Gelalcha Benti D, Gelgie Aga E, Kerro Dego Oudessa
Department of Animal Science, The University of Tennessee, Knoxville, TN, United States.
Front Vet Sci. 2023 Dec 18;10:1260433. doi: 10.3389/fvets.2023.1260433. eCollection 2023.
The extended-spectrum beta-lactamase (ESBL)-producing such as , are emerging as a serious threat to global health due to their rapid spread and their multidrug-resistant (MDR) phenotypes. However, limited information is available regarding the prevalence and antimicrobial resistance (AMR) profile of ESBL- in the United States dairy farms. This study aimed to determine the prevalence and AMR pattern of ESBL- in East Tennessee dairy cattle farms.
Rectal fecal samples from dairy cattle ( = 508) and manure ( = 30), water ( = 19), and feed samples ( = 15) were collected from 14 farms. The presumptive was isolated on CHROMagar™ ESBL and confirmed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). Antimicrobial susceptibility testing was performed on the ESBL- isolates.
From 572 fecal and farm environmental samples, a total of 233 (41%, = 572) ESBL- were identified. The prevalence of fecal ESBL- was 47.5% (95% CI: 46.2-49.2). The within-farm prevalence of ESBL- ranged from 8 to 100%. Recent treatment history with third-generation cephalosporins (3GC), cow parity ≥3, and calves were the independent risk factors associated ( < 0.05) with fecal carriage of ESBL-. Overall, 99.6% ( = 231) ESBL- tested were phenotypically resistant to at least one of the 14 antimicrobial agents tested. The most common AMR phenotypes were against beta-lactam antibiotics, ampicillin (99.1%; = 231 isolates), and ceftriaxone (98.7%, = 231). Most ESBL- isolates (94.4%) were MDR (resistance to ≥3 antimicrobial classes), of which 42.6% showed co-resistance to at least six classes of antimicrobials. ESBL- isolates with concurrent resistance to ceftriaxone, ampicillin, streptomycin, tetracycline, sulfisoxazole, and chloramphenicol are widespread and detected in all the farms. The detection of MDR ESBL- suggests that dairy cattle can be a reservoir for these bacteria, highlighting the associated public health risk.
产超广谱β-内酰胺酶（ESBL）的细菌，如大肠杆菌，由于其迅速传播和多重耐药（MDR）表型，正成为全球健康的严重威胁。然而，关于美国奶牛场中ESBL产生菌的流行情况和抗菌药物耐药性（AMR）概况的信息有限。本研究旨在确定东田纳西州奶牛场中ESBL产生菌的流行情况和AMR模式。
从14个农场收集了奶牛的直肠粪便样本（n = 508）以及粪便（n = 30）、水（n = 19）和饲料样本（n = 15）。在CHROMagar™ ESBL培养基上分离疑似菌株，并通过基质辅助激光解吸/电离飞行时间质谱（MALDI-TOF MS）进行确认。对ESBL产生菌分离株进行抗菌药物敏感性测试。
从572份粪便和农场环境样本中，共鉴定出233株（41%，n = 572）ESBL产生菌。粪便中ESBL产生菌的流行率为47.5%（95%置信区间：46.2 - 49.2）。农场内ESBL产生菌的流行率在8%至100%之间。近期使用第三代头孢菌素（3GC）的治疗史、奶牛胎次≥3以及犊牛是与粪便携带ESBL产生菌相关的独立危险因素（P < 0.05）。总体而言，99.6%（n = 231）的测试ESBL产生菌对所测试的14种抗菌药物中的至少一种表现出表型耐药。最常见的AMR表型是对β-内酰胺类抗生素、氨苄西林（99.1%；n = 231株分离株）和头孢曲松（98.7%，n = 231）耐药。大多数ESBL产生菌分离株（94.4%）为多重耐药（对≥3类抗菌药物耐药），其中42.6%对至少六类抗菌药物表现出共同耐药。同时对头孢曲松、氨苄西林、链霉素、四环素、磺胺异恶唑和氯霉素耐药的ESBL产生菌分离株广泛存在，且在所有农场均有检测到。多重耐药ESBL产生菌的检测表明奶牛可能是这些细菌的储存宿主，突出了相关的公共卫生风险。
