牛奶中吡利霉素残留消除规律试验研究

Depletion of pirlimycin residue in milk by UPLC-MS/MS

研究吡利霉素在牛奶中的残留消除规律。常规饲养条件下,对6头健康奶牛乳房注入方式给予盐酸吡利霉素乳房注入剂(5 mg/mL),每个乳区10 mL,连续2次给药,间隔24 h。停药后分别于第6、12、24、36、48、60、72、96和120 h对每头奶牛4个乳区挤得的混合奶进行采样,用超高效液相色谱-串联质谱(UPLC-MS/MS)法测定各时间点牛奶中吡利霉素的残留量,结果统计以盐酸吡利霉素残留消除规律曲线及平均消除规律曲线表示。结果表明:吡利霉素在牛奶中的残留消除较快,48 h时6头奶牛牛奶中吡利霉素残留量平均值为94.0μg/L,已低于最高残留限量MRL(100μg/L),到60 h时6头奶牛每头牛奶样品中的残留量都低于MRL。试验结果说明,新药吡利霉素弃奶期的制定应跟据我国具体情况进一步研究确定,笔者初步研究认为48 h较为适宜。

The objective was to study the depletion of pirlimycin residue in milk with time after milking , Six healthy dairy cows were administered pirlimycin hydrochloric acid by breast infusion twice at a dosage of 10 mg/10 mL for two consecutive days at 24 h intervals, The cows were milked at 6, 12, 24, 36, 48, 60, 72, 96, 120 h after the second administration. The residue of pirlimycin in milk was determined with an ultra high performance liquid chromatographytandem mass spectrometry （UPLC-MS/MS）. There was a rapid depletion of pirlimycin in milk and the mean level of residue in the six cows （94.01 g/L） at 48 h and every 60 h was less than MRL （100 μg/L）.