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                                                                   Exhibit 10.12

                      FISHER SCIENTIFIC INTERNATIONAL INC.

            SECOND AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT

         This SECOND AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT (this
"AMENDMENT") is dated as of February 25, 2004, and entered into by and among
FISHER SCIENTIFIC INTERNATIONAL INC. ("COMPANY"), FISHER SCIENTIFIC COMPANY
L.L.C. ("FSCLLC"; Company and FSCLLC are each individually referred to herein as
a "BORROWER" and collectively as "BORROWERS"), THE FINANCIAL INSTITUTIONS LISTED
ON THE SIGNATURE PAGES HEREOF, DEUTSCHE BANK AG, NEW YORK BRANCH (in its
capacity as administrative agent, the "ADMINISTRATIVE AGENT" or "DEUTSCHE
BANK"), DEUTSCHE BANK SECURITIES INC., as Joint Lead-Arranger, BANC OF AMERICA
SECURITIES LLC, as Joint Lead-Arranger and CREDIT SUISSE FIRST BOSTON, acting
through its Cayman Islands Branch, and BANK OF AMERICA N.A., as Syndication
Agents, and solely for purpose of Section 2 hereof, the Credit Support Parties
(as defined in Section 2 hereof), and is made with reference to that certain
Amended and Restated Credit Agreement, dated as of September 10, 2003, as
amended (the "CREDIT AGREEMENT"), by and among Borrowers, Lenders and the
predecessor Administrative Agent. Capitalized terms used herein without
definition shall have the same meanings herein as set forth in the Credit
Agreement.

                                    RECITALS

         WHEREAS, Borrowers desire to make certain amendments to the Credit
Agreement as set forth below;

         NOW, THEREFORE, in consideration of the premises and the agreements,
provisions and covenants herein contained, the parties hereto agree as follows:

         SECTION 1. AMENDMENTS TO THE CREDIT AGREEMENT

         1.1 AMENDMENTS TO SECTION 1.01: DEFINED TERMS.

            A. Section 1.01 of the Credit Agreement is hereby amended as
follows:

                (i) The definition of "Consolidated EBITDA" is amended by
restating clause (a)(xii) thereof to read in its entirety as follows:

                  "(xii) cash fees and expenses paid or incurred in connection
         with Perbio Transaction Investments and the Oxoid Transaction
         Investments;".


                (ii) The definition of "Consolidated EBITDA" is amended by
restating the third sentence thereof to read in its entirety as follows:

                  "If the allocation of the purchase price for the Perbio
         Acquisition or the Oxoid Acquisition results in a write-up in the book
         value of any inventory owned by
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         Perbio and its subsidiaries or Oxoid and its subsidiaries, then (except
         for purposes of calculating the Total Leverage Ratio to determine the
         Applicable Rate) Consolidated EBITDA shall be calculated as though such
         write-up had not occurred.".

                (iii) The definition of "Net Investment Amount" is amended as
follows:

                  A. Clause (v) of clause (a) is restated to read in its
entirety as follows:

                  "(v) Perbio Transaction Investments and Oxoid Transaction

         Investments".

                  B. The second parenthetical in clause (b) is amended to read
in its entirety as follows:

                  "(excluding (A) any such dividends, distributions or payments
by a Subsidiary the investments in which were made in reliance on clause (l) of
Section 6.04, or by an Excluded Subsidiary or a Receivables Subsidiary or in
respect of any Subordinated Receivables Transfer Debt, any Perbio Transaction
Investments or any Oxoid Transaction Investments, (B) any such Net Proceeds from
the sale or disposition of investments in Subsidiaries made in reliance on
clause (l) of Section 6.04, the sale or disposition of an Excluded Subsidiary,
the sale or disposition of investments in a Receivables Subsidiary or any
Subordinated Receivables Transfer Debt, any Perbio Transaction Investments or
any Oxoid Transaction Investments and (C) Special Notes)".

                (iv) Clause (f) of the definition of "Permitted Acquisition" is
restated to read in its entirety as follows:

                "(f) the Company and the Subsidiaries are in compliance, on a
pro forma basis after giving effect to such acquisition, with the covenants
contained in Sections 6.12, 6.13 and 6.14 recomputed as of the last day of the
most recently ended fiscal quarter of the Company for which financial statements
are available as if such acquisition had occurred on the first day of each
relevant period for testing compliance (but measuring Total Indebtedness for
purposes of Section 6.13 and Senior Indebtedness for purposes of Section 6.14 as
of the date of such acquisition, giving effect to incurrences and prepayments of
Indebtedness since such last day of the most recently ended fiscal quarter),".

                (v) The following defined terms are added to Section 1.01 of the
Credit Agreement in their appropriate alphabetical position:

                ""Oxoid" means Oxoid Group Holdings Limited.

                "Oxoid Acquisition" means the acquisition by a wholly-owned
Subsidiary of the Company of all or substantially all of the outstanding Equity
Interests of Oxoid, pursuant to the Oxoid Acquisition Agreement.

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                "Oxoid Acquisition Agreement" means that certain Share Sale
Agreement relating to the acquisition of the entire issued share capital of
Oxoid, to be entered into among the vendors listed therein, the Company, and PPM
Ventures Limited, in the form of the draft that was delivered to the
Administrative Agent on February 9, 2004, with such amendments and other
modifications and related documents as the Administrative Agent, in its
reasonable discretion, determines are not materially adverse to the
Administrative Agent or the Lenders.

                "Oxoid Acquisition Debt" means up to $350,000,000 in aggregate
principal amount of Indebtedness incurred within 60 days of the closing of the
Oxoid Acquisition (a) which satisfies the requirements of Senior Debt and (b)
all of the net proceeds of which are used to finance or refinance a portion or
all of the Oxoid Transaction Investments.

                "Oxoid Transaction Investments" means an aggregate amount of up
to $400,000,000 of investments, consisting of (a) the acquisition of Equity
Interests from time to time in Oxoid pursuant to the Oxoid Acquisition, (b)
additional investments in Oxoid to the extent necessary to repay Indebtedness of
Oxoid and its subsidiaries outstanding at the time that the outstanding Equity
Interests of Oxoid are acquired pursuant to the Oxoid Acquisition, (c) any cash
loans and advances to, or other cash investments in, Foreign Subsidiaries made
by the Company or any Subsidiary Guarantor, to the extent that the proceeds
thereof are used directly or indirectly to make investments described in clause
(a) or (b) above or to pay fees and expenses incurred in connection with the
Oxoid Acquisition, and (d) Equity Interests in the Company to the extent used
directly or indirectly to make investments described in clauses (a) or (b)
above; provided that if the aggregate amount of investments described in clauses
(a) through (d) above exceeds $400,000,000, such excess investments shall not
constitute Oxoid Transaction Investments, but may nonetheless be permitted under
this Agreement so long as such investments otherwise comply with the terms and
conditions of this Agreement.".

         1.2 AMENDMENT TO SECTION 2.20.

            Section 2.20 of the Credit Agreement is hereby amended by deleting
clause (a)(ii) and restating it to read as follows:

                  "(ii) the aggregate principal amount of Senior Debt issued
         after the Effective Date in excess of the sum of (x) the outstanding
         amount of Oxoid Acquisition Debt plus (y) $400,000,000 (if the Senior
         Leverage Ratio is greater than or equal to 3.50 to 1.00 at the time
         such Incremental Term Loan is incurred (after giving pro forma effect
         to the Incremental Term Loan to be incurred)), $525,000,000 (if the
         Senior Leverage Ratio is less than 3.50 to 1.00 but greater than or
         equal to 3.00 to 1.00 at the time such Incremental Term Loan is
         incurred (after giving pro forma effect to the Incremental Term Loan to
         be incurred)) or $650,000,000 (if the Senior Leverage Ratio is less
         than 3.00 to 1.00 at the time such Incremental Term Loan is incurred
         (after giving pro forma effect to the Incremental Term Loan to be
         incurred)),".

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         1.3 AMENDMENT TO SECTION 6.01.

            Section 6.01 of the Credit Agreement is hereby amended by deleting
clause (xi) of Section 6.01(a) and restating it to read as follows:

                  "(xi) Senior Debt; provided that (A) the aggregate principal
         amount of Senior Debt incurred after the Effective Date and outstanding
         at any time in reliance on this clause (xi) shall not exceed the sum of
         (x) the outstanding amount of Oxoid Acquisition Debt plus (y) either
         (1) if the Senior Leverage Ratio is equal to or greater than 3.50 to
         1.00 at the time such Senior Debt is incurred (after giving pro forma
         effect to the Senior Debt to be incurred), $400,000,000, plus, if at
         the time Senior Debt is issued in excess of $400,000,000 there remains
         any unutilized amount of the maximum principal amount of Incremental
         Term Loans allowed to be incurred under Section 2.20, such unutilized
         amount, or in the alternative (2) if the Senior Leverage Ratio is less
         than 3.50 to 1.00 but greater than or equal to 3.00 to 1.00 at the time
         such Senior Debt is incurred (after giving pro forma effect to the
         Senior Debt to be incurred), $525,000,000, plus, if at the time Senior
         Debt is issued in excess of $525,000,000 there remains any unutilized
         amount of the maximum principal amount of Incremental Term Loans
         allowed to be incurred under Section 2.20, such unutilized amount, or
         in the alternative (3) if the Senior Leverage Ratio is less than 3.00
         to 1.00 at the time such Senior Debt is incurred (after giving pro
         forma effect to the Senior Debt to be incurred), $650,000,000, plus, if
         at the time Senior Debt is issued in excess of $650,000,000 there
         remains any unutilized amount of the maximum principal amount of
         Incremental Term Loans allowed to be incurred under Section 2.20, such
         unutilized amount, and (B) the Net Proceeds of all Senior Debt shall be
         used to finance Permitted Acquisitions or to refinance Term Loans or
         outstanding Senior Debt;".

         1.4 AMENDMENT TO SECTION 6.04.

            Section 6.04 of the Credit Agreement is hereby amended by deleting
the proviso in clause (a) thereof and restating it to read as follows:

                  "provided that, at the time of and after giving effect to each
         Perbio Transaction Investment, each Oxoid Transaction Investment and,
         in each case, any Indebtedness incurred in connection therewith, the
         sum of (i) the amount of cash and Permitted Investments, in each case,
         that are owned by the Company or a Domestic Subsidiary and that are not
         subject to any Lien (other than a Lien under the Security Documents),
         plus (ii) the unused Revolving Commitments plus (iii) the cash proceeds
         available under the Permitted Receivables Financing, shall not be less
         than $100,000,000;".

         1.5 AMENDMENT TO SECTION 6.07.

            Section 6.07 of the Credit Agreement is hereby amended by deleting
the parenthetical clause in clause (iii)(y) of Section 6.07(c) and restating it
to read as follows:

            "(adjusted to exclude (1) cash fees and expenses paid or incurred in
connection with Perbio Transaction Investments or Oxoid Transaction Investments,
(2) charges and expenses of up to $50,000,000 in the aggregate in respect of the
Redemption and the

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establishment of the Company's current Permitted Receivables Financing and the
credit facilities established under this Agreement, (3) noncash expenses
attributable to grants of stock, restricted stock or stock options and other
noncash stock-based awards (including but not limited to performance units,
stock appreciation rights, restricted stock units or dividend equivalents
payable solely in shares of stock) and (4) the effects of any write-up in the
book value of any inventory owned by Perbio and its subsidiaries or Oxoid and
its subsidiaries resulting from the allocation of the purchase price for the
Perbio Acquisition or the Oxoid Acquisition, as the case may be)".

         SECTION 2. ACKNOWLEDGEMENT AND CONSENT

            A. Each of the Initial Borrower and each other Subsidiary Guarantor
(each individually a "CREDIT SUPPORT PARTY" and collectively, the "CREDIT
SUPPORT PARTIES") has read this Amendment and consents to the terms hereof and
further hereby confirms and agrees that, notwithstanding the effectiveness of
this Amendment, the obligations of such Credit Support Party under each of the
Loan Documents to which such Credit Support Party is a party shall not be
impaired and each of the Loan Documents to which such Credit Support Party is a
party is, and after the Second Amendment Effective Date shall continue to be, in
full force and effect and are hereby confirmed and ratified in all respects.

            B. Each Subsidiary Guarantor (other than Initial Borrower)
acknowledges and agrees that (i) notwithstanding the conditions to effectiveness
set forth in this Amendment, such Credit Support Party is not required by the
terms of the Credit Agreement or any other Loan Document to consent to the
amendments to the Credit Agreement effected pursuant to this Amendment and (ii)
nothing in the Credit Agreement, this Amendment or any other Loan Document shall
be deemed to require the consent of such Credit Support Party to any future
amendments to the Credit Agreement.

         SECTION 3. CONDITIONS TO EFFECTIVENESS

            This Amendment shall become effective only upon the satisfaction of
all of the conditions precedent (the date of satisfaction of all such conditions
precedent being referred to herein as the "SECOND AMENDMENT EFFECTIVE DATE") set
forth in this Section 3.

            A. CORPORATE DOCUMENTS. On or before the Second Amendment Effective
Date, each Borrower shall, and shall cause each other Credit Support Party to,
deliver to Lenders (or to Administrative Agent for Lenders with sufficient
originally executed copies, where appropriate, for each Lender and its counsel)
the following, each, unless otherwise noted, dated the Second Amendment
Effective Date:

                  (i) A good standing certificate from the Secretary of State of
         each Borrower's and each Credit Support Party's jurisdiction of
         organization, dated a recent date prior to the Second Amendment
         Effective Date.

                  (ii) Certified copies of the Certificate or Articles of
         Incorporation or the certificate of formation, as the case may be, of
         each Borrower dated a recent date prior to the Second Amendment
         Effective Date.

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                  (iii) Resolutions of the Board of Directors or managing
         member, as the case may be, of each Borrower approving and authorizing
         the execution, delivery, and performance of this Amendment, certified
         as of the Second Amendment Effective Date by its corporate secretary or
         an assistant secretary as being in full force and effect without
         modification or amendment.

                  (iv) Signature and incumbency certificates of the officers or
         managing members of each Borrower and each Credit Support Party
         executing this Amendment.

            B. AMENDMENT. Administrative Agent shall have signed a counterpart
of this Amendment and Administrative Agent or its counsel shall have received
from the Borrowers, the Credit Support Parties and the Required Lenders (i) a
counterpart of this Amendment signed on behalf of each such party or (ii)
written evidence satisfactory to Administrative Agent (which may include
electronic mail or telecopy transmission of a signed signature page of this
Amendment) that each such party has signed a counterpart of this Amendment.

            C. PAYMENT OF FEES AND EXPENSES. (i) On or before the Second
Amendment Effective Date, the Administrative Agent shall have received from the
Borrowers for the benefit of each Lender that shall have signed and delivered a
counterpart to this Amendment to the Administrative Agent (including, without
limitation, delivery via facsimile or electronic mail) on or before 5:00 p.m.
(New York time) on February 25, 2004, an amendment fee equal to 0.05% of the sum
as of such date of (a) such Lender's Revolving Commitment (without regard to
availability or utilization at such time) and (b) the aggregate outstanding
principal amount of Term Loans held by such Lender.

            (ii) The Company shall have paid or caused to be paid to
Administrative Agent all amounts owing to Administrative Agent or any of its
Affiliates on or prior to the Second Amendment Effective Date, including,
without limitation, all of Administrative Agent's reasonable out-of-pocket costs
and expenses as described in Section 10.03 of the Credit Agreement incurred by
Administrative Agent (including, without limitation, the reasonable fees and
disbursements of O'Melveny & Myers LLP) in connection with this Amendment and
the documents and transactions related hereto.

            D. COMPLETION OF PROCEEDINGS. On or before the Second Amendment
Effective Date, all corporate and other proceedings taken or to be taken in
connection with the transactions contemplated hereby and all documents
incidental thereto not previously found acceptable by Administrative Agent,
acting on behalf of Lenders, and its counsel shall be satisfactory in form and
substance to Administrative Agent and its counsel, and Administrative Agent and
such counsel shall have received all such counterpart originals or certified
copies of such documents as Administrative Agent may reasonably request.

         SECTION 4. REPRESENTATIONS AND WARRANTIES

            In order to induce Lenders and Administrative Agent to enter into
this Amendment and to amend the Credit Agreement in the manner provided herein,
the Company represents and warrants to Administrative Agent and each Lender that
the following statements are true, correct and complete:

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            A. AUTHORIZATION; ENFORCEABILITY. Each Borrower has all requisite
corporate or limited liability company power and authority to enter into this
Amendment. The execution, delivery and performance of this Amendment have been
duly authorized by all necessary corporate or limited liability company action
by each Borrower. This Amendment has been duly executed and delivered by each
Borrower and constitutes when executed and delivered, the legally valid and
binding obligation of such Borrower, enforceable against such Borrower in
accordance with its terms, except as enforceability may be limited by
bankruptcy, insolvency, reorganization, moratorium or other laws affecting or
limiting creditors' rights generally and by equitable principles relating to
enforceability, regardless of whether considered as a proceeding in equity or at
law.

            B. GOVERNMENT APPROVALS; NO CONFLICT. The execution and delivery by
each Borrower of this Amendment (a) do not require any consent or approval of,
registration or filing with, or any other action by, any Governmental Authority,
except such as have been obtained or made and are in full force and effect and
except filings necessary to perfect Liens created under the Loan Documents, (b)
will not violate any applicable law or regulation in any material respect or the
charter, by-laws or other organizational documents of any Borrower or any order
of any Governmental Authority, (c) will not violate in any material respect or
result in a default under any indenture, agreement or other instrument binding
upon any Borrower or its assets, or give rise to a right thereunder to require
any payment to be made by any Borrower, and (d) will not result in the creation
or imposition of any Lien on any asset of any Borrower, except Liens created
under the Loan Documents.

            C. INCORPORATION OF REPRESENTATIONS. The representations and
warranties of each Loan Party set forth in the Loan Documents are true and
correct in all material respects on and as of the Second Amendment Effective
Date, except to the extent such representations and warranties expressly relate
to an earlier date, in which case such representations and warranties shall have
been true and correct as of such earlier date.

            D. ABSENCE OF DEFAULT. No event has occurred and is continuing or
would result from the execution, delivery or performance of this Amendment that
constitutes or would constitute an Event of Default or a Default after giving
effect to this Amendment.

            E. PERMITTED ACQUISITION. The Oxoid Acquisition, when consummated,
will constitute a Permitted Acquisition under the Credit Agreement, as amended
by this Amendment.

         SECTION 5. MISCELLANEOUS

            A. REFERENCE TO AND EFFECT ON THE CREDIT AGREEMENT AND THE OTHER
LOAN DOCUMENTS.

                  (i) On and after the Second Amendment Effective Date, each
         reference in the Credit Agreement to "this Agreement", "hereunder",
         "hereof", "herein" or words of like import referring to the Credit
         Agreement, and each reference in the other Loan Documents to the
         "Credit Agreement", "thereunder", "thereof" or words of like import
         referring to the Credit Agreement shall mean and be a reference to the
         Credit Agreement, as amended by this Amendment.

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                  (ii) Except as specifically amended by this Amendment, the
         Credit Agreement and the other Loan Documents shall remain in full
         force and effect and are hereby ratified and confirmed.

                  (iii) The execution, delivery and performance of this
         Amendment shall not, except as expressly provided herein, constitute a
         waiver of any provision of, or operate as a waiver of any right, power
         or remedy of Administrative Agent, or any Lender under, the Credit
         Agreement or any of the other Loan Documents.

            B. FEES AND EXPENSES. Loan Parties acknowledge that all costs, fees
and expenses as described in Section 10.03 of the Credit Agreement incurred by
the Administrative Agent and its counsel with respect to this Amendment and the
documents and transactions contemplated hereby shall be for the account of Loan
Parties.

            C. HEADINGS. Section and Section headings in this Amendment are
included herein for convenience of reference only and shall not constitute a
part of this Amendment for any other purpose or be given any substantive effect.

            D. APPLICABLE LAW. THIS AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF
THE PARTIES HEREUNDER SHALL BE GOVERNED BY, AND SHALL BE CONSTRUED AND ENFORCED
IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK.

            E. COUNTERPARTS. This Amendment may be executed in any number of
counterparts and by different parties hereto in separate counterparts, each of
which when so executed and delivered shall be deemed an original, but all such
counterparts together shall constitute but one and the same instrument;
signature pages may be detached from multiple separate counterparts and attached
to a single counterpart so that all signature pages are physically attached to
the same document.

                 [Remainder of page intentionally left blank.]

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

BORROWERS:

                                 FISHER SCIENTIFIC INTERNATIONAL INC.,

                                 By:  _______________________________________
                                      Name:
                                      Title:



                                 FISHER SCIENTIFIC COMPANY L.L.C.,

                                 By: Fisher Scientific International Inc.,
                                         manager and sole member

                                 By:  _______________________________________
                                      Name:
                                      Title:


CREDIT SUPPORT PARTIES:
(FOR PURPOSES OF SECTION 2)

                                 COLE-PARMER INSTRUMENT COMPANY,

                                 By:  _______________________________________
                                      Name:
                                      Title:



                                 FISHER CLINICAL SERVICES INC.,

                                 By:  _______________________________________
                                      Name:
                                      Title:
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                                 FISHER HAMILTON L.L.C.,

                                 By: Fisher Scientific International Inc.,
                                         manager and sole member


                                 By:  _______________________________________
                                      Name:
                                      Title:


                                 FISHER SCIENTIFIC WORLDWIDE INC.,

                                 By:  _______________________________________
                                      Name:
                                      Title:



                                 FSWH COMPANY LLC

                                 By:  _______________________________________
                                      Name:
                                      Title:


                                 HYCLONE LABORATORIES, INC.

                                 By:  _______________________________________
                                      Name:
                                       Title:


                                 PIERCE MILWAUKEE, INC.

                                 By:  _______________________________________
                                      Name:
                                       Title:


                                 PIERCE BIOTECHNOLOGY, INC.

                                 By:  _______________________________________
                                      Name:
                                       Title:
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LENDERS:

                                 DEUTSCHE BANK AG, NEW YORK BRANCH,
                                 as Administrative Agent and Lender

                                 By: _________________________________________
                                     Name:
                                     Title:

                                 and

                                 By: _________________________________________
                                     Name:
                                     Title:
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                                 CREDIT SUISSE FIRST BOSTON, ACTING THROUGH ITS
                                 CAYMAN ISLANDS BRANCH, as Syndication Agent and
                                 Lender

                                 By: _________________________________________
                                     Name:
                                     Title:

                                        and

                                 By: _________________________________________
                                     Name:
                                     Title:
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                                 BANK OF AMERICA, N.A.,
                                 as Syndication Agent and Lender

                                 By: _________________________________________
                                     Name:
                                     Title: