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                                                                   Exhibit 10.2


                                                                        ANNEX I


                      AMENDMENT NO. 1 TO CREDIT AGREEMENT


       THIS AMENDMENT NO. 1 TO CREDIT AGREEMENT (this "AMENDMENT"), dated as of
April 18, 2001, among Charles River Laboratories, Inc., a Delaware corporation
(the "BORROWER"), Charles River Laboratories International, Inc. (f/k/a Charles
River Laboratories Holdings, Inc.), a Delaware corporation ("HOLDCO"), Credit
Suisse First Boston (as successor in interest to DLJ Capital Funding, Inc.), as
lead arranger, as sole book runner and as syndication agent (in such capacity,
the "SYNDICATION AGENT") for the Lenders (as defined below), and Fleet National
Bank (as successor in interest to Union Bank of California, N.A.), as
administrative agent (the "ADMINISTRATIVE AGENT") for the Lenders.

                              W I T N E S S E T H:

       WHEREAS, the Borrower, Holdco, certain financial institutions (together
with their respective successors and assigns, the "LENDERS"), the Syndication
Agent and the Administrative Agent are parties to the Amended and Restated
Credit Agreement, dated as of February 2, 2001 (as heretofore modified and
supplemented and in effect from time to time, the "EXISTING CREDIT AGREEMENT"
and as further amended hereby, the "CREDIT AGREEMENT");

       WHEREAS, the Borrower desires, and the Lenders are willing, on the terms
and subject to the conditions hereinafter set forth, to amend the Existing
Credit Agreement as set forth herein;

       NOW, THEREFORE, the parties hereto hereby agree as follows:

                                     PART I
                                   DEFINITIONS

       SUBPART 1.1. CERTAIN DEFINITIONS. Unless otherwise defined herein or the
context otherwise requires, terms used in this Amendment, including its preamble
and recitals, have the following meanings (such meanings to be equally
applicable to the singular and plural forms thereof):

       "ADMINISTRATIVE AGENT" is defined in the PREAMBLE.

       "AMENDMENT" is defined in the PREAMBLE.

       "AMENDMENT EFFECTIVE DATE" is defined in SUBPART 3.1.

       "BORROWER" is defined in the PREAMBLE.

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       "CREDIT AGREEMENT" is defined in the FIRST RECITAL.

       "EXISTING CREDIT AGREEMENT" is defined in the FIRST RECITAL.

       "HOLDCO" is defined in the PREAMBLE.

       "LENDERS" is defined in the FIRST RECITAL.

       "SYNDICATION AGENT" is defined in the PREAMBLE.

       SUBPART 1.2. OTHER DEFINITIONS. Unless otherwise defined herein or the
context otherwise requires, terms used in this Amendment, including its preamble
and recitals, have the meanings set forth in the Existing Credit Agreement. Each
reference to "hereof", "hereunder", "herein" and "hereby" and each other similar
reference and each reference to "this Agreement" and each other similar
reference contained in the Existing Credit Agreement shall from and after the
Amendment Effective Date refer to the Credit Agreement.


                                     PART II
                         AMENDMENTS TO CREDIT AGREEMENT

       Effective on (and subject to the occurrence of) the Amendment Effective
Date, the Existing Credit Agreement is hereby amended in accordance with this
Part II. Except to the extent amended by this Amendment, the Credit Agreement is
and shall continue to be in full force and effect and is hereby ratified and
confirmed in all respects.

       SUBPART 2.1. AMENDMENTS TO ARTICLE I. Article I of the Existing Credit
Agreement is amended as set forth in this Subpart 2.1.

       (a) The following definitions are added to such Article and inserted in
the appropriate alphabetical order:

            "AMENDMENT NO. 1" means Amendment No. 1 to Credit Agreement, dated
       as of April 18, 2001, among the Borrower, Holdco and the Agents, which
       amendment was consented to by the Lenders constituting the Required
       Lenders.

       (b) The definition of "Change in Control" is hereby amended and restated
in its entirety as follows:

            (i) "CHANGE IN CONTROL" means the failure of Holdco at any time to
       own, free and clear of all Liens and encumbrances (other than Liens of
       the types permitted to exist under CLAUSES (b), (d) and (g) of SECTION
       7.2.3), all right, title and interest in 100% of the Capital Stock of the
       Borrower; (ii) any "person" or "group" (as such terms are used in Rule
       13d-5 of the Exchange Act, and Sections 13(d) and 14(d) of the Exchange
       Act) of persons (other than DLJMBP and its Affiliates or members of
       management of the

                                      -2-

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       Borrower) becomes, directly or indirectly, in a single transaction or in
       a related series of transactions by way of merger, consolidation, or
       other business combination or otherwise, the "beneficial owner" (as such
       term is used in Rule 13d-3 of the Exchange Act) of more than 30% of the
       total voting power in the aggregate of all classes of Capital Stock of
       Holdco then outstanding entitled to vote generally in elections of
       directors of Holdco; or (iii) during any period of 24 consecutive months,
       individuals who at the beginning of such period constituted the Board of
       Directors of Holdco (together with any new directors whose election to
       such Board or whose nomination for election by the stockholders of the
       Borrower was approved by DLJMBP and its Affiliates or a vote of a
       majority of the directors then still in office who were either directors
       at the beginning of such period or whose election or nomination for
       election was previously so approved) cease for any reason to constitute a
       majority of the Board of Directors of Holdco then in office.

                                    PART III
                           CONDITIONS TO EFFECTIVENESS

       SUBPART 3.1. AMENDMENT EFFECTIVE DATE. This Amendment shall become
effective as of March 15, 2001 (the "AMENDMENT EFFECTIVE DATE") when the Agents
shall have received counterparts of this Amendment, duly executed by the
Borrower, Holdco, the Syndication Agent and the Administrative Agent on behalf
of the Required Lenders who shall have delivered to the Administrative Agent
their written consent to the amendments, as explicitly set forth herein and
subject to the terms hereof.


                                     PART IV
                                  MISCELLANEOUS

       SUBPART 4.1. EXPENSES. The Borrower hereby agrees to pay and reimburse
the Syndication Agent for all its reasonable fees and expenses incurred in
connection with the negotiation, preparation, execution and delivery of this
Amendment and related documents, including all reasonable fees and disbursements
of counsel to the Syndication Agent.

       SUBPART 4.2. BORROWER REPRESENTATION AND WARRANTY. The delivery of an
executed counterpart hereof by the Borrower shall constitute a representation
and warranty by the Borrower that:

            (a) on the Amendment Effective Date, after giving effect to this
       Amendment, all representations, warranties and other statements set forth
       in Article VI of the Existing Credit Agreement, as then amended by this
       Amendment, are true and correct as of such date, except to the extent
       that such representation, warranty or statement expressly relates to an
       earlier date (in which case such representation, warranty or statement
       shall have been true and correct on and as of such earlier date); and

            (b) this Amendment constitutes the legal, valid and binding
       obligation of the Borrower enforceable in accordance with its terms
       subject to the effects of bankruptcy,

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       insolvency, fraudulent conveyance, reorganization, moratorium and other
       similar laws relating to or affecting creditors' rights generally,
       general equitable principles (whether considered in a proceeding in
       equity or at law) and an implied covenant of good faith and fair dealing.

       SUBPART 4.3. LOAN DOCUMENT PURSUANT TO CREDIT AGREEMENT. This Amendment
is a Loan Document executed pursuant to the Credit Agreement and shall (unless
otherwise expressly indicated therein) be construed, administered and applied in
accordance with all of the terms and provisions of the Credit Agreement, as
amended hereby.

       SUBPART 4.4. SUCCESSORS AND ASSIGNS. This Amendment shall be binding upon
and inure to the benefit of the parties hereto and their respective successors
and assigns.

       SUBPART 4.5. COUNTERPARTS. This Amendment may be executed by the parties
hereto in several counterparts, each of which when executed and delivered shall
be an original and all of which shall constitute together but one and the same
agreement.

       SUBPART 4.6. GOVERNING LAW. THIS AMENDMENT SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE INTERNAL LAWS OF THE STATE OF NEW YORK.

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       IN WITNESS WHEREOF, the parties S-1 S-1 hereto have executed and
delivered this Amendment as of the date first above written.


BORROWER:                               CHARLES RIVER LABORATORIES, INC.


                                        By:
                                           -------------------------------------
                                           Name:
                                           Title:


HOLDCO:                                 CHARLES RIVER LABORATORIES
                                          INTERNATIONAL, INC. (f/k/a Charles
                                          River Laboratories Holdings, Inc.)


                                        By:
                                           -------------------------------------
                                           Name:
                                           Title:


AGENTS:                                 CREDIT SUISSE FIRST BOSTON (as
                                          successor in interest to DLJ Capital
                                          Funding, Inc.), as Syndication Agent


                                        By:
                                           -------------------------------------
                                           Name:
                                           Title:


                                        By:
                                           -------------------------------------
                                           Name:
                                           Title:


                                        FLEET NATIONAL BANK,
                                          as Administrative Agent


                                        By:
                                           -------------------------------------
                                           Name:
                                           Title: