Anderson K L, Moats W A, Rushing J E, O'Carroll J M
Department of Food Animal and Equine Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh 27606, USA.
Am J Vet Res. 1998 Sep;59(9):1096-100.
To compare results of 6 commercially available milk antimicrobial screening tests with results of liquid chromatography (LC) when testing milk samples from individual cows treated for mild clinical mastitis by intramammary (IMM) infusion with amoxicillin or penicillin G.
6 cows with noninduced clinical mastitis: 3 treated by IMM infusion with amoxicillin and 3 treated by IMM infusion with penicillin G.
Composite milk samples were collected before, during, and after treatment. Samples were assayed by use of the screening tests and their results and those of LC were compared. The LC results were assumed to represent the true result.
Results of screening tests compared well with results of LC, with agreement of 94%. Positive screening test results for samples containing drug values below the established tolerance or safe level, as evaluated by LC, were obtained from 2 cows in which abnormal milk, as well as marked increases in composite milk somatic cell count, were observed. With the exception of 1 test in 1 cow, all screening tests had negative results at the end of the labeled milk-withholding time.
On the basis of results of the limited sample reported, the screening tests appeared to provide good agreement overall, compared with LC results, when testing milk of individual cows treated by IMM infusion with amoxicillin or penicillin G. Positive screening test results for milk samples containing amoxicillin or penicillin G at values below the established tolerance or safe level, as evaluated by LC, may occasionally be obtained.
比较6种市售牛奶抗菌筛选试验的结果与液相色谱法（LC）的结果，这些试验用于检测经乳房内（IMM）注入阿莫西林或青霉素G治疗轻度临床乳腺炎的个体奶牛的牛奶样本。
6头非诱导性临床乳腺炎奶牛：3头经IMM注入阿莫西林治疗，3头经IMM注入青霉素G治疗。
在治疗前、治疗期间和治疗后采集混合牛奶样本。使用筛选试验对样本进行检测，并将其结果与LC的结果进行比较。假定LC结果代表真实结果。
筛选试验结果与LC结果比较吻合，符合率为94%。对于LC评估显示药物值低于既定耐受或安全水平的样本，2头奶牛的筛选试验结果呈阳性，这2头奶牛的牛奶异常，且混合牛奶体细胞计数显著增加。除1头奶牛的1次试验外，所有筛选试验在标记的禁奶期结束时均为阴性结果。
根据所报告的有限样本结果，当检测经IMM注入阿莫西林或青霉素G治疗的个体奶牛的牛奶时，与LC结果相比，筛选试验总体上似乎具有良好的吻合度。偶尔可能会获得LC评估显示阿莫西林或青霉素G值低于既定耐受或安全水平的牛奶样本的筛选试验阳性结果。
