EXHIBIT 21 LIST OF SUBSIDIARIES The following table sets forth certain information concerning the principal subsidiaries of the Company. State or Other Name Jurisdiction of Incorporation ----- ----------------------------- All-Glass Aquarium Co., Inc. Wisconsin Four Paws Products, Ltd. New York Kaytee Products Incorporated Wisconsin Norcal Pottery Products, Inc. California Pennington Seed, Inc. of Delaware Delaware TFH Publications, Inc. Delaware Wellmark International California The names of certain subsidiaries have been omitted because such unnamed subsidiaries, considered in the aggregate, would not constitute a significant subsidiary as that term is defined in Regulation S-X.