Korkeala H, Sorvettula O, Mäki-Petäys O, Hirn J
Acta Vet Scand. 1982;23(3):407-15. doi: 10.1186/BF03546792.
The different agar diffusion methods were compared using antibiotic and sulphonamide-impregnated filter-paper discs and the kidneys of healthy and emergency-slaughtered pigs and cows after slaughter. No method used seemed to be sensitive to all antimicrobial drugs preimpregnated onto discs. Tetracycline yielded a greater zone of inhibition at pH 6 than at pH 8 and aminoglycosides, erythromycin, polymyxin B and lin cornycin at pH 8 than at pH 6. It therefore seems necessary to use different pHs (6 and 8). The addition of trimethoprim to the medium is necessary for the detection of sulphonamides. Bacillus subtilis BGA used as the test organism was more sensitive to sulphonamides on the “Test agar for the inhibitor test” containing trimethoprim than on the “Iso-Sensitest agar” also containing trimethoprim. The addition of trimethoprim to “Test agar for the inhibitor test” is recommended at pH 8 but not at pH 6 because false-positive cases (with inhibition zones > 2 mm) were observed at pH 6 with trimethoprim on the kidneys of healthy pigs.
使用浸渍抗生素和磺胺的滤纸圆盘以及屠宰后健康猪和牛以及急宰猪和牛的肾脏，对不同的琼脂扩散方法进行了比较。所使用的方法似乎都不对预先浸渍在圆盘上的所有抗菌药物敏感。四环素在pH 6时产生的抑菌圈比在pH 8时更大，而氨基糖苷类、红霉素、多粘菌素B和林肯霉素在pH 8时比在pH 6时产生的抑菌圈更大。因此，似乎有必要使用不同的pH值（6和8）。在培养基中添加甲氧苄啶对于磺胺类药物的检测是必要的。用作测试菌的枯草芽孢杆菌BGA在含有甲氧苄啶的“抑制剂测试用测试琼脂”上比在同样含有甲氧苄啶的“异感测试琼脂”上对磺胺类药物更敏感。建议在pH 8时向“抑制剂测试用测试琼脂”中添加甲氧苄啶，但在pH 6时不添加，因为在pH 6时，在健康猪的肾脏上使用甲氧苄啶观察到了假阳性情况（抑菌圈>2毫米）。
