FIRST AMENDMENT TO AGREEMENT AND PLAN OF MERGER


      This FIRST AMENDMENT TO AGREEMENT AND PLAN OF MERGER, dated as of
September 14, 2000 (this "First Amendment"), is entered into by and between
PETCO Animal Supplies, Inc., a Delaware corporation (the "Company"), and BD
Recapitalization Corp., a Delaware corporation ("MergerSub").

                            R E C I T A L S

      WHEREAS, the Company and MergerSub entered into that certain Agreement and
Plan of Merger, dated as of May 17, 2000 (the "Merger Agreement");

      WHEREAS, the Company and MergerSub wish to amend the Merger Agreement to
reduce the Termination Fee (as defined in Section 10.2 of the Merger Agreement);
and

      WHEREAS, the Special Committee (as defined in the Merger Agreement), the
Board of Directors of the Company and the sole stockholder of MergerSub have
each approved and adopted this First Amendment and have approved the
transactions contemplated hereby;

      NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto agree as
follows:

      1.   SECTION 10.2(a). Section 10.2(a) of the Merger Agreement is amended
           to reduce the Termination Fee (as defined in the Merger Agreement)
           from $11 million to $5 million.

      2.   RELATIONSHIP TO MERGER AGREEMENT. Consistent and in accordance with
Section 11.3 of the Merger Agreement, the parties hereto acknowledge that, other
than as expressly provided in this First Amendment, this First Amendment shall
have no effect on the rights, obligations, duties (fiduciary or otherwise) or
remedies available or




due under the Merger Agreement or applicable law, whether legal, equitable or
otherwise.

      3.   GOVERNING LAW.  This First Amendment shall be governed by
and construed in accordance with the laws of the State of Delaware.

      4.   COUNTERPARTS.  This First Amendment may be executed in one or more
counterparts which, when taken together, shall constitute one and the same
instrument.






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      IN WITNESS WHEREOF, the parties hereto have caused this First Amendment to
be duly executed by their respective authorized officers as of the day and year
first above written.



                                   PETCO ANIMAL SUPPLIES, INC.


                                   By:  /s/ JAMES M. MYERS
                                       -------------------------------
                                       Name:  James M. Myers
                                       Title: Senior Vice President
                                              and Chief Financial
                                              Officer

                                   BD RECAPITALIZATION CORP.


                                   By:  /s/ JOHN G. DANHAKL
                                       -------------------------------
                                       Name:  John G. Danhakl
                                       Title: President





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