Abstract The modified fluorometric procedure for nequinate in feed eliminates the need for column separation and is well suited for practical routine feed analysis. Nequinate is extracted from feed with 1% formic acid in CHCl3. The extract is filtered and diluted with CHCl3. Methanesulfonic acid is added to enhance the fluorescence of nequinate and the fluorescence is determined at a 270 nm excitation wavelength and a 372 nm emission wavelength. The average recovery of nequinate from feed is 100.5% with a standard deviation of 2.2%. In the presence of most feed additives, the method is quite specific for nequinate. Other 4-hydroxy quinoline coccidiostats presently used as feed additives produce a low level of fluorescence, but qualitative differences can be detected at low concentrations in the presence of methanesulfonic acid due to the lack of a sharp 270 nm excitation peak.