Abstract: This experiment aimed to investigate the elimination profile of phenoxymethylpenicillin（penicillin V potassium）soluble powder in eggs. Ten healthy laying hens meeting the required egg production criteria. They were administered the drug orally via drinking water at the maximum recommended clinical dose of 20 mg/kg B.W./d for 5 consecutive days. Freshly prepared medicated water was provided daily and ensured to be fully consumed by the flock.Eggs were collected daily at fixed time points from the start of administration until 14 days after the last dose，with detailed records maintained. Quantitative analysis was performed using an internal standard method. After sample pretreatment，penicillin V residues in eggs were determined by LC?MS/MS. The method demonstrated good linearity within the concentration range of 5－200 ng/mL，with a limit of detection of 5 μg/kg. Recoveries ranged from 96% to 101.4%，with RSD≤3.5%. Penicillin V residues were rapidly eliminated from eggs，falling below the detection limit by the first day post?treatment. Based on the maximum residue limit（MRL）regulations for penicillin V，a withdrawal period of zero days is recommended for phenoxymethylpenicillin soluble powder in laying hens.

Key words: Phenoxymethylpenicillin；Eggs；Drug residue；Withdrawal

摘要： 该文旨在研究青霉素V钾可溶性粉在鸡蛋中的消除规律。选取健康且产蛋率符合 试验要求的10羽蛋鸡进行试验，以临床最大推荐剂量20 mg/kg B.W./d混饮给药，连续给药5 d，每日新配药液，并保证鸡群在当日饮用完毕。给药期间至末次给药后14 d内，每天定点收 集鸡蛋样品并做好记录，采用内标法定量。样品经前处理后用LC?MS/MS法分析，对鸡蛋中青 霉素V残留标志物进行残留检测。结果表明，该方法在5－200 ng/mL浓度范围内线性关系良 好，检测限为5 μg/kg，回收率在96%－101.4%，RSD≤3.5%。残留在鸡蛋中青霉素V消除较 快，第1 d的鸡蛋中青霉素V残留限量低于检测限。综合青霉素V的最大残留限量规定，建议 青霉素V钾可溶性粉在蛋鸡中的休药期为0 d。

关键词: 青霉素V钾；鸡蛋；药物残留；休药期