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                                                                     Exhibit 5.1


                        [LETTERHEAD OF LATHAM & WATKINS]


                                 March 18, 2002


PETCO Animal Supplies, Inc.
9125 Rehco Road
San Diego, CA 92121

                  Re:      REGISTRATION STATEMENT RELATING TO $200,000,000
                           AGGREGATE PRINCIPAL AMOUNT OF 10.75% SENIOR
                           SUBORDINATED NOTES DUE 2011
                           -----------------------------------------------


Ladies and Gentlemen:

                  In connection with the registration of $200,000,000 aggregate
principal amount of 10.75% Senior Subordinated Notes due 2011 (the "Exchange
Notes") by PETCO Animal Supplies, Inc., a Delaware corporation (the "Company"),
and the guarantees of the Exchange Notes (the "Guarantees") by the guarantors
listed on SCHEDULE A hereto (each, a "Guarantor" and collectively, the
"Guarantors"), under the Securities Act of 1933, as amended, on Form S-4 filed
with the Securities and Exchange Commission on March 18, 2002 (the "Registration
Statement"), you have requested our opinion with respect to the matters set
forth below. The Exchange Notes and Guarantees will be issued pursuant to an
indenture dated as of October 26, 2001 (the "Indenture"), among the Company, the
Guarantors and U.S. Bank N.A., as trustee (the "Trustee").

                  In our capacity as your counsel in connection with such
registration, we are familiar with the proceedings taken by the Company and the
Guarantors in connection with the authorization and issuance of the Exchange
Notes and the Guarantees, respectively. In addition, we have made such legal and
factual examinations and inquiries, including an examination of originals or
copies certified or otherwise identified to our satisfaction of such documents,
corporate records and instruments, as we have deemed necessary or appropriate
for purposes of this opinion.

                  In our examination, we have assumed the genuineness of all
signatures, the authenticity of all documents submitted to us as originals, and
the conformity to authentic original documents of all documents submitted to us
as copies.

                  We are opining herein as to the effect on the subject
transaction only of the internal laws of the State of New York and the General
Corporation Law of the State of Delaware, and we express no opinion with respect
to the applicability thereto, or the effect thereon, of the laws of any other
jurisdiction or, in the case of Delaware, any other laws, or as to any matters
of municipal law or the laws of any local agencies within any state.


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LATHAM & WATKINS
PETCO Animal Supplies, Inc.
March 18, 2002
Page 2


                  Subject to the foregoing and the other matters set forth
herein, it is our opinion that as of the date hereof:

                  1. The Exchange Notes have been duly authorized by all
necessary corporate action of the Company, and when executed, authenticated and
delivered in accordance with the terms of the Exchange Offer and the Indenture,
will constitute legally valid and binding obligations of the Company,
enforceable against the Company in accordance with their terms.

                  2. Each of the Guarantees has been duly authorized by all
necessary corporate or partnership action, as the case may be, of the respective
Guarantor, and when executed in accordance with the terms of the Indenture and
upon due execution, authentication and delivery of the Exchange Notes in
accordance with the terms of the Exchange Offer and the Indenture, will be the
legally valid and binding obligation of the respective Guarantor, enforceable
against such Guarantor in accordance with its terms.

                  The opinions rendered in paragraphs 1 and 2 relating to the
enforceability of the Exchange Notes and the Guarantees are subject to the
following exceptions, limitations and qualifications: (i) the effect of
bankruptcy, insolvency, reorganization, moratorium or other similar laws now or
hereafter in effect relating to or affecting the rights and remedies of
creditors; and (ii) the effect of general principles of equity, whether
enforcement is considered in a proceeding in equity or law, and the discretion
of the court before which any proceeding therefor may be brought.

                  We have not been requested to express, and with your knowledge
and consent, do not render any opinion with respect to the applicability to the
obligations of the Company under the Indenture and the Exchange Notes or the
Guarantors under the Indenture or the Guarantees of Section 548 of the United
States Bankruptcy Code or applicable state law (including, without limitation,
Article 10 of the New York Debtor and Creditor Law) relating to fraudulent
transfers and obligations.

                  To the extent that the obligations of the Company and the
Guarantors under the Exchange Notes and the Indenture may be dependent upon such
matters, we assume for purposes of this opinion that: (i) the Trustee is duly
organized, validly existing and in good standing under the laws of its
jurisdiction of organization; (ii) the Trustee is duly qualified to engage in
the activities contemplated by the Indenture; (iii) the Indenture has been duly
authorized, executed and delivered by the Trustee and constitutes the legally
valid, binding and enforceable obligation of the Trustee, enforceable against
the Trustee in accordance with its terms; (iv) the Trustee is in compliance
generally and with respect to acting as a trustee under the Indenture, with all
applicable laws and regulations; and (v) the Trustee has the requisite
organizational and legal power and authority to perform its obligations under
the Indenture.


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LATHAM & WATKINS
PETCO Animal Supplies, Inc.
March 18, 2002
Page 3

                  We consent to your filing this opinion as an exhibit to the
Registration Statement and to the reference to our firm contained under the
heading "Legal Matters."

                                              Very truly yours,

                                              /s/ LATHAM & WATKINS

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                                   SCHEDULE A

                                   GUARANTORS



International Pet Supplies and Distribution, Inc.

Pet Concepts International

PETCO Southwest, Inc.

PETCO Southwest, L.P.

PM Management Incorporated