EXHIBIT 21 SUBSIDIARIES OF THE REGISTRANT NEOGEN CORPORATION AND SUBSIDIARIES MAY 31, 2000 PERCENTAGE OWNED STATE INCORPORATED BY NEOGEN CORPORATION ================================================================================ Neogen Research Corporation II Michigan 90% Neogen Research Corporation IV Michigan 100% Ideal Instruments, Inc. Michigan 100% AMPCOR Diagnostics, Inc. Michigan 100% Acumedia Manufacturers, Inc. Maryland 100% ================================================================================ All of the subsidiaries listed above are included in the consolidated financial statements of Neogen Corporation.