产前饲喂模式下恩诺沙星在初产蛋中的残留规律及膳食暴露评估

Assessment of residue regularity and dietary exposure of enrofloxacin in primiparous eggs under prenatal feeding mode

目的探讨产前饲喂模式下恩诺沙星在初产蛋中残留规律,评估其对鸡蛋的安全性以及消费者健康的影响。方法选取378只日龄为85 d的海兰褐蛋鸡,根据给药时间分为14组, 1.5 g/(kg·BW)恩诺沙星粉剂连续拌料喂药5 d。从给药后生产第1枚鸡蛋开始连续采集鸡蛋8 d,采用液相色谱-串联质谱法分析鸡蛋中恩诺沙星及其代谢产物环丙沙星的残留量,采用每日允许摄入量对初产蛋的安全性进行评估。结果初产蛋中恩诺沙星和环丙沙星含量均随着停药时间延长逐渐降低。连续给药5 d,停药1 d的初产蛋中恩诺沙星和环丙沙星含最高,分别为959.725和62.263mg/kg,停药7 d后鸡蛋中环丙沙星含量低于检出限,恩诺沙星代谢缓慢,停药24 d后鸡蛋中恩诺沙星含量低于检出限。停药1 d的初产蛋对婴儿和成年人身体健康具有慢性危害风险。结论为了保证禽蛋中无恩诺沙星残留,建议至少需要在产蛋前29 d用药,停药24 d以上,以满足产品符合国家监管以及保证消费者健康的要求。

Objective To assess the residual regularity of enrofloxacin in the primiparous eggs of hens under prenatal feeding mode, and evaluate its impact on the safety of eggs and on the health of consumers. Methods A total of 378 Hailan brown hens(85 days old) were divided into 14 groups according to the time of administration, fed by 1.5 g/(kg·BW) enrofloxacin supplemented diet for 5 days. Eggs were collected continuously when the first egg was layed after 8 days of administration. The residues of enrofloxacin and its metabolite ciprofloxacin in eggs were analyzed by liquid chromatography-tandem mass spectrometry, and the safety was evaluated by acceptable daily intake. Results The content of enrofloxacin and ciprofloxacin in the primiparous eggs gradually decreased with the extending time of the drug withdrawal. The highest levels of enrofloxacin and ciprofloxacin in primiparous eggs after administration for 5 days and withdrawal for 1 day were 959.725 g/kg and 62.263 g/kg, respectively. After 7 days of drug withdrawal, the ciprofloxacin content in eggs was lower than the detection limit. However, trace enrofloxacin in eggs was metabolized slowly. The content of enrofloxacin in eggs was lower than the detection limit after 24 days of drug withdrawal. The primiparous eggs after 1 day of drug withdrawal showed a chronic risk of harm to the health of baby and adults. Conclusion In order to ensure that no enrofloxacin residue in poultry eggs, it is recommended that feed the drug at least 29 days prior to egg laying and withdrawal the drug for more than 24 days to meet the requirements of national supervision as well as to ensure consumer health.