Kilonzo-Nthenge A, Nahashon S N, Godwin S, Liu S, Long D
Department of Family and Consumer Science, Tennessee State University, 3500 John A. Merritt Boulevard, Nashville, Tennessee 37209, USA.
Department of Agricultural Sciences, Tennessee State University, 3500 John A. Merritt Boulevard, Nashville, Tennessee 37209, USA.
J Food Prot. 2016 Dec;79(12):2031-2037. doi: 10.4315/0362-028X.JFP-16-032.
Public health concerns over the emergence of antimicrobial resistant bacteria have increased recently. The purpose of this study was to investigate the prevalence of antimicrobial resistant Enterobacteriaceae in shell eggs purchased from small poultry farms and farmers' markets. A total of 504 eggs were pooled to make 252 composite samples, consisting of 2 eggs per composite. The microbial quality of shell eggs was determined by standard quantitative, biochemical, and PCR techniques. Susceptibility to 13 antimicrobial agents was determined by the Kirby-Bauer disk diffusion technique, and results were interpreted based on Clinical and Laboratory Standards Institute values. Shell eggs and egg contents were positive for Escherichia coli (11.9 and 5.2%, respectively), Enterobacter (9.1 and 7.9%), and Serratia (11.5 and 4.8%). Salmonella was isolated from 3.6% of egg shells but not from egg contents. Mean (±SD) Enterobacteriaceae levels (4.4 ± 2.0 log CFU per eggshell) on shell eggs from poultry farms was significantly higher (P ≤ 0.05) than that on shell eggs from farmers' markets (2.1 ± 1.3 log CFU per eggshell). Of the 134 isolates recovered, resistance among isolates from farm and market shell eggs to erythromycin was most common (48.5 and 32.8%, respectively) followed by ampicillin (44.8 and 17.2%), and tetracycline (29.9 and 17.2%). The multiple antibiotic resistance index value for E. coli and Pantoea was 0.62, and that for Salmonella and Klebsiella terrigena was 0.08, indicating that Enterobacteriaceae in shell eggs can be resistant to multiple antimicrobial agents. These data reveal that shell eggs from small poultry farms and farmers' markets can harbor antimicrobial resistant pathogenic and commensal bacteria. Thus, failure to properly handle shell eggs poses a potential health hazard to consumers.
近期，公众对耐药菌出现的健康担忧有所增加。本研究的目的是调查从小型家禽养殖场和农贸市场购买的带壳鸡蛋中耐抗菌药物肠杆菌科细菌的流行情况。总共收集了504枚鸡蛋，制成252个混合样本，每个混合样本包含2枚鸡蛋。通过标准定量、生化和PCR技术测定带壳鸡蛋的微生物质量。采用 Kirby-Bauer 纸片扩散法测定对13种抗菌药物的敏感性，并根据临床和实验室标准协会的值解释结果。带壳鸡蛋及其内容物中大肠杆菌呈阳性（分别为11.9%和5.2%）、肠杆菌呈阳性（9.1%和7.9%）、沙雷氏菌呈阳性（11.5%和4.8%）。从3.6%的蛋壳中分离出沙门氏菌，但未从蛋内容物中分离出。家禽养殖场带壳鸡蛋上的肠杆菌科细菌平均水平（±标准差）（每枚蛋壳4.4±2.0 log CFU）显著高于（P≤0.05）农贸市场带壳鸡蛋上的水平（每枚蛋壳2.1±1.3 log CFU）。在回收的134株分离菌中，养殖场和市场带壳鸡蛋分离菌对红霉素的耐药最为常见（分别为48.5%和32.8%），其次是氨苄西林（44.8%和17.2%）和四环素（29.9%和17.2%）。大肠杆菌和泛菌的多重耐药指数值为0.62，沙门氏菌和土生克雷伯菌的多重耐药指数值为0.08，表明带壳鸡蛋中的肠杆菌科细菌可对多种抗菌药物耐药。这些数据表明，小型家禽养殖场和农贸市场的带壳鸡蛋可能携带耐抗菌药物的致病和共生细菌。因此，未能妥善处理带壳鸡蛋会对消费者构成潜在的健康危害。
