EXHIBIT 32.1 SECTION 906 -- CERTIFICATION OF CHIEF EXECUTIVE OFFICER OF PERIODIC FINANCIAL REPORT Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, 18 U.S.C. Section 1350, and in connection with the accompanying Quarterly Report on Form 10-Q of Doane Pet Care Company for the quarter ended September 27, 2003 (the "Report"), the undersigned officer of Doane Pet Care Company hereby certifies that: 1. The Report fully complies with the requirements of Section 15(d) of the Securities Exchange Act of 1934; and 2. The information contained in the Report fairly presents, in all material respects, the financial condition and results of the operations of Doane Pet Care Company. Date: October 30, 2003 /s/ Douglas J. Cahill ----------------------------------- Douglas J. Cahill President and Chief Executive Officer Doane Pet Care Company