In 2019, the U.S. Department of Agriculture’s (USDA) Food Safety and Inspection Service (FSIS) provided revised guidance for labeling claims of “raised without antibiotics” (RWA) and similar terms for meat and poultry produced in the US. In 2022, Price et al. published a study reporting that 15% of RWA-labeled cattle contained antibiotic residues in urine samples. In 2023, the USDA embarked on the project reported herein to independently determine the extent of antibiotic drug residues present in kidney and liver tissues from slaughtered cattle purported to be RWA. In this study, FSIS inspectors randomly collected kidney and liver tissues from 189 RWA animals in 79 slaughter establishments across the US. The samples were monitored for 185 veterinary drugs multiple times by different means, including liquid-chromatography coupled with tandem mass spectrometry (LC-MS/MS) and quadrupole high-resolution MS with an orbital ion trap instrument (LC-Q/orbitrap). Samples from 37 animals (20%) met the analytical identification criteria for at least one antibiotic confirmed in at least two analyses. Multiple antibiotics were determined in 11 RWA animals. Macrolides (tulathromycin, tildipirosin, tilmicosin, and gamithromycin) were confirmed in 20 (11%) of the RWA animals. The ionophore, monensin, was also confirmed in tissues from 11 samples, with unconfirmed/partial identifications in 8 others. Tetracyclines were confirmed in samples from 12 animals, several of which were found to contain multiple antibiotic residues. One animal each was also found to be positive for sulfamethazine (a sulfonamide antibiotic) and metabolites of penicillin G (a β-lactam antibiotic). Although they are not antibiotics, two anthelmintics (fenbendazole and eprinomectin) were confirmed in tissues from 3 RWA animals. FSIS has informed the slaughter establishments with positive results and advised them to conduct a root cause analysis and implement corrective actions.

中文翻译：

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据报道，在没有抗生素的情况下饲养的牛体内的抗生素残留


2019 年，美国农业部 （USDA） 食品安全和检验局 （FSIS） 为美国生产的肉类和家禽提供了修订后的指南，用于“无抗生素饲养”（RWA） 和类似术语的标签声明。2022 年，Price 等人发表了一项研究，报告称 15% 的 RWA 标记牛在尿液样本中含有抗生素残留。2023 年，美国农业部开始了本文报道的项目，以独立确定据称是 RWA 的屠宰牛的肾脏和肝脏组织中存在的抗生素药物残留的程度。在这项研究中，FSIS 检查员从美国 79 个屠宰场的 189 只 RWA 动物中随机收集了肾脏和肝脏组织。通过不同方法对 185 种兽药进行多次监测，包括液相色谱-串联质谱 （LC-MS/MS） 和四极杆高分辨率 MS 与轨道离子阱仪 （LC-Q/orbitrap）。来自 37 只动物 （20%） 的样品符合至少一种抗生素的分析鉴定标准，至少在两次分析中得到确认。在 11 只 RWA 动物中测定了多种抗生素。大环内酯类药物（tulathromycin、tildipirosin、tilmicosin 和 gamithromycin）在 20 只 （11%） 的 RWA 动物中得到证实。离子载体莫能菌素也在 11 个样本的组织中得到证实，另外 8 个样本未得到证实/部分鉴定。在 12 只动物的样本中证实了四环素类药物，其中几种被发现含有多种抗生素残留。还发现各一只动物对磺胺二甲嘧啶（一种磺胺类抗生素）和青霉素 G（一种 β-内酰胺类抗生素）的代谢物呈阳性。 虽然它们不是抗生素，但在 3 只 RWA 动物的组织中证实了两种驱虫药 （芬苯达唑和依维菌素）。FSIS 已将积极结果通知屠宰场，并建议他们进行根本原因分析并实施纠正措施。