Inhibition of Growth for Select Gram-Negative Bacteria by Tricaine Methane Sulfonate (MS-222)
J Herpe Med Surg 15[1]:13-17 Jun'05 Prospective Study 13 Refs

Tricaine methane sulfonate (MS-222 or Tricaine) is a commonly used agent for anesthesia and euthanasia in aquatic organisms. Bacterial diseases are routinely discovered in captive aquatic vertebrates, and bacterial culture is often performed to identify potential pathogens. Currently, no study has evaluated the effect of MS-222 on bacterial isolation from the aquatic environment. Minimum inhibitory concentration tests using a gradient of MS-222 were performed for 11 species of Gram-negative bacteria isolated from aquatic environments. MS-222 inhibited the growth of all bacterial species at 5000 mg/L, while bacterial growth was depressed at MS-222 concentrations as low as 200 mg/L. Based on these findings, special care should be taken when interpreting the results of bacterial culture when MS-222 is used to anesthetize or euthanize fish or amphibians. [Abstract]