Submitted to: Book of Abstracts Aquaculture America
Publication Type: Abstract only
Publication Acceptance Date: 11/19/2007
Publication Date: 2/10/2008
Citation: Darwish, A.M., Farmer, B.D., Hawke, J.P. 2008. Improved method for minimum inhibitory concentration testing of flavobacterium columnare [abstract]. Book of Abstracts Aquaculture America. p.84. Interpretive Summary:
Technical Abstract: A simple and reliable microdilution method has been developed to test the susceptibility of Flavobacterium columnare to antibiotics in vitro. The method has been used to determine the minimum inhibitory concentration (MIC) of 23 F. columnare isolates. The tests were conducted at 28 °C using a standardized inoculum, Mueller Hinton broth at 1/5 of the full strength (4 g/L), a reference isolate, positive and negative control wells and standardized custom made microtitre plates, Sensititre® Susceptibility Plates for Aquaculture (Trek Diagnostic Systems, Inc.). Escherichia coli ATCC25922 was found to be acceptable as a reference isolate and produced MIC values similar to the range published by the Clinical and Laboratory Standards Institute (CLSI), formally the National Committee for Clinical Laboratory Standards (NCCLS) on standard Mueller Hinton. Mueller Hinton broth at 1/5 of the full strength (4 g/L) was found to support superior growth of Escherichia coli ATCC25922 and F. columnare ATCC23463, the species type strain, than Mueller Hinton broth at 1/7 of the full strength.