Musser J M, Anderson K L, Rushing J E, Moats W A
Department of Farm Animal Health and Resource Management, College of Veterinary Medicine, North Carolina State University, Raleigh 27606, USA.
J Dairy Sci. 2001 Jan;84(1):126-33. doi: 10.3168/jds.S0022-0302(01)74460-8.
The potential for antibiotic residues in calves from consuming milk containing penicillin G or amoxicillin was investigated. Six calves were fed milk replacer, 6% body weight twice daily, containing 0.293, 2.92, or 5.85 microg of penicillin/ml (ppm) G or 0.25, 1.0, or 2.0 microg of amoxicillin/ml for three consecutive feedings. Urine and blood samples were collected after each feeding. Serum and urine samples were tested with a microbial receptor assay and a microbial growth inhibition assay to indicate potential drug residues. Penicillin G and amoxicillin were detected in the serum and urine of several calves 3 h after drinking spiked milk replacer. Possible violative drug residues in the calves were detected by the microbial growth inhibition assay up to 15 h after drinking spiked milk replacer. Penicillin G, but not amoxicillin, could be detected in urine 24 h after the final feeding of spiked milk replacer. Subsequently, six calves were fed milk replacer containing 11.7 microg of penicillin G/ml (ppm) twice daily, 6% body weight per feeding. Calves were slaughtered 3 h after the final feeding. Mean (+/-SD) concentrations of penicillin G measured by high-pressure liquid chromatography in liver, kidney, muscle, and serum were 0.409 (+/-0.167) microg/g, 0.031 (+/-0.012) microg/g 0.008 (+/-0.002) microg/g, and 0.013 (+/-0.006) mg/ml, respectively. This study indicates that calves fed milk with amoxicillin or penicillin G could possibly have violative residues if slaughtered within 24 h after feeding. Violative drug residues in liver tissue were found in calves slaughtered 3 h after consuming milk replacer containing 11.7 microg of penicillin G/ml (ppm).
研究了犊牛食用含青霉素G或阿莫西林牛奶后抗生素残留的可能性。六头犊牛每天两次喂食代乳粉，每次喂食量为体重的6%，代乳粉中分别含有0.293、2.92或5.85微克/毫升（ppm）的青霉素G，或0.25、1.0或2.0微克/毫升的阿莫西林，连续喂食三次。每次喂食后采集尿液和血液样本。血清和尿液样本通过微生物受体测定法和微生物生长抑制测定法进行检测，以指示潜在的药物残留。饮用添加药物的代乳粉3小时后，在几头犊牛的血清和尿液中检测到了青霉素G和阿莫西林。通过微生物生长抑制测定法在饮用添加药物的代乳粉后长达15小时检测到犊牛体内可能存在违规药物残留。在最后一次喂食添加药物的代乳粉24小时后，尿液中可检测到青霉素G，但检测不到阿莫西林。随后，六头犊牛每天两次喂食含11.7微克/毫升（ppm）青霉素G的代乳粉，每次喂食量为体重的6%。在最后一次喂食3小时后宰杀犊牛。通过高压液相色谱法测得肝脏、肾脏、肌肉和血清中青霉素G的平均（±标准差）浓度分别为0.409（±0.167）微克/克、0.031（±0.012）微克/克、0.008（±0.002）微克/克和0.013（±0.006）毫克/毫升。本研究表明，喂食含阿莫西林或青霉素G牛奶的犊牛，如果在喂食后24小时内宰杀，可能会有违规残留。在食用含11.7微克/毫升（ppm）青霉素G的代乳粉后3小时宰杀的犊牛肝脏组织中发现了违规药物残留。
