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                                                                     EXHIBIT 4.3

                                                               EXECUTION VERSION


                           SEVENTH AMENDMENT dated as of August 9, 2005 (this
                  "Amendment"), to the AMENDED AND RESTATED FIVE-YEAR CREDIT
                  AGREEMENT dated as of October 11, 2001 (as amended,
                  supplemented or otherwise modified from time to time, the
                  "Credit Agreement"), among LAND O'LAKES, INC., a cooperative
                  corporation organized under the laws of the State of Minnesota
                  (the "Borrower"), the several banks and other financial
                  institutions and entities from time to time party thereto (the
                  "Lenders"), and JPMORGAN CHASE BANK, N.A., as administrative
                  agent (in such capacity, the "Administrative Agent").

         A. Capitalized terms used but not defined herein shall have the
meanings assigned to such terms in the Credit Agreement, as amended hereby.

         B. The Borrower has notified the Administrative Agent that it intends
to effect an initial public offering pursuant to which it will offer and sell
shares of the common stock of CF Industries Holdings, Inc. ("CFI") in an
underwritten offering registered with the Securities and Exchange Commission
(the "CF IPO"). The Borrower currently owns approximately 38% of the Equity
Interests in CF Industries, Inc., a wholly owned subsidiary of CFI, and intends
to use up to the full amount of the Net Proceeds (as defined below) from the CFI
IPO to finance the repurchase of its Senior Notes, Senior Second Lien Notes
and/or Capital Securities or any combination thereof.

         C. The Borrower has requested that the Lenders amend certain provisions
of the Credit Agreement in connection with the CFI IPO and its intended use of
the Net Proceeds of the CFI IPO and certain other sales of Equity Interests of
CFI as set forth herein.

         D. The Required Lenders are willing to effect such amendments on the
terms and subject to the conditions of this Amendment.

         E. Accordingly, in consideration of the mutual agreements herein
contained and other good and valuable consideration, the sufficiency and receipt
of which are hereby acknowledged, the parties hereto agree as follows:

         SECTION 1. Amendment of the Credit Agreement. Effective as of the
Amendment Effective Date:

         (a) Section 1.01 of the Credit Agreement is amended to add definitions
of the following terms in appropriate alphabetical order:

         'CFI' means CF Holdings Industries, Inc., a Delaware corporation, and
    its wholly owned subsidiary, CF Industries, an Illinois corporation, in
    which the Borrower owns approximately 38% of the Equity Interests.


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         'CFI IPO' means an initial public offering pursuant to which the
    Borrower will offer and sell shares of the common stock of CFI in an
    underwritten offering registered with the Securities and Exchange
    Commission.

         'CFI Residual Shares' means the Equity Interests in CFI which are
    required to be retained by the Borrower in connection with the CFI IPO
    pursuant to a lock-up agreement between the Borrower and the underwriters
    managing the CFI IPO, which Equity Interests the Borrower may elect to sell
    on a date at least 12 months after the closing date of the CFI IPO.

         'Net Proceeds' means the cash proceeds received by the Borrower from
    the (a) CFI IPO and (b) the sale of any CFI Residual Shares, in each case
    net of all reasonable fees and out-of-pocket expenses, including without
    limitation legal fees, accountants' fees, underwriters' fees or placement
    agents' fees, discounts or commissions, and other fees paid by the Borrower
    to third parties (other than Affiliates) in connection with the CFI IPO.

         'Seventh Amendment' means the Seventh Amendment, dated as of August 9,
    2005, to this Agreement.

         'Seventh Amendment Effective Date' means the date on which the Seventh
    Amendment became effective in accordance with Section 3 thereof.

         (b) Amendment of Subsection 6.05. Subsection 6.05 of the Credit
Agreement is amended by (i) deleting the word "and" at the end of paragraph (g),
(ii) inserting the word "and" at the end of paragraph (h) and (iii) inserting a
new paragraph (i) that reads in its entirety as follows:

         "(i) the sale by the Borrower of (x) the Equity Interests in CFI in
    connection with the CFI IPO and (y) the CFI Residual Shares;"

         (c) Amendment of Subsection 6.08(b). Subsection 6.08(b) is amended by
(i) inserting the words ", and will not" immediately following the words "The
Borrower will not" in the first line of such Subsection, and (ii) (x) deleting
the word "and" at the end of clause (vi), (y) deleting the period at the end of
clause (vii) and replacing it with "; and" and (z) inserting a new clause (viii)
that reads in its entirety as follows:

         "(viii) the Borrower may repurchase any combination of the Senior
    Notes, the Senior Second Lien Notes and/or the Capital Securities in an
    aggregate amount, including accrued and unpaid interest and any redemption
    premiums, not to exceed the greater of (a) $100,000,000 and (b) the Net
    Proceeds; provided that (x) after giving effect to any such repurchase, the
    aggregate principal amount of undrawn Letters of Credit and Loans
    outstanding under the Credit Agreement does not exceed $100,000,000 and (y)
    no Default exists at the time of any such repurchase."

         SECTION 2. Representations and Warranties. To induce the other parties
hereto to enter into this Amendment, the Borrower represents and warrants to
each


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of the Lenders, the Administrative Agent and the Collateral Agent that, as of
the Amendment Effective Date:

         (a) This Amendment has been duly authorized, executed and delivered by
it and this Amendment and the Credit Agreement, as amended hereby, constitutes
its legal, valid and binding obligation, enforceable against it in accordance
with its terms except as such enforceability may be limited by bankruptcy,
insolvency, reorganization, moratorium or other similar laws affecting
creditors' rights generally and by general principles of equity (regardless of
whether such enforceability is considered in a proceeding at law or in equity).

         (b) The representations and warranties set forth in Article III of the
Credit Agreement are, after giving effect to this Amendment, true and correct in
all material respects on and as of the Amendment Effective Date with the same
effect as though made on and as of the Amendment Effective Date, except to the
extent such representations and warranties expressly relate to an earlier date
(in which case they were true and correct in all material respects as of such
earlier date).

         (c) No Default or Event of Default has occurred and is continuing.

         (d) After giving effect to this Amendment, the Collateral and Guarantee
Requirement has been satisfied.

         SECTION 3. Effectiveness. This Amendment and the amendment of the
Credit Agreement effected hereby shall become effective as of the first date
(the "Amendment Effective Date") on which the following conditions have been
satisfied:

         (a) The Administrative Agent (or its counsel) shall have received duly
executed counterparts hereof that, when taken together, bear the signatures of
(i) the Administrative Agent, (ii) the Borrower, and (iii) the Required Lenders.

         (b) The Administrative Agent shall have received a certificate of a
Financial Officer to the effect that the representations and warranties set
forth in Section 2 hereof are true and correct on and as of the Amendment
Effective Date.

         (c) The Administrative Agent shall have received such documents and
certificates as the Administrative Agent or its counsel may reasonably request
relating to the authorization of this Amendment and the transactions
contemplated hereby and any other legal matters relating to the Loan Parties,
this Amendment, and the transactions contemplated hereby, all in form and
substance reasonably satisfactory to the Administrative Agent.

         (d) The Administrative Agent shall have received all fees and other
amounts due from any Loan Party hereunder or under the Credit Agreement or any
other Loan Document on or prior to the Amendment Effective Date and, to the
extent invoiced on or prior to the Amendment Effective Date, reimbursement or
payment of all out-of-pocket expenses (including fees, charges and disbursements
of counsel) required to be


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reimbursed or paid by any Loan Party hereunder or under the Credit Agreement or
any other Loan Document.

The Administrative Agent shall notify the Borrower and the Lenders of the
Amendment Effective Date, and such notice shall be conclusive and binding.

         SECTION 4. Effect of Amendment. (a) Except as expressly set forth
herein, this Amendment shall not by implication or otherwise limit, impair,
constitute a waiver of or otherwise affect the rights and remedies of the
Lenders, the Administrative Agent or the Collateral Agent under the Credit
Agreement or any other Loan Document, and shall not alter, modify, amend or in
any way affect any of the terms, conditions, obligations, covenants or
agreements contained in the Credit Agreement or any other provision of the
Credit Agreement or of any other Loan Document, all of which are ratified and
affirmed in all respects and shall continue in full force and effect. Nothing
herein shall be deemed to entitle the Borrower to a consent to, or a waiver,
amendment, modification or other change of, any of the terms, conditions,
obligations, covenants or agreements contained in the Credit Agreement or any
other Loan Document in similar or different circumstances.

         (b) On and after the Amendment Effective Date, each reference in the
Credit Agreement to "this Agreement", "hereunder", "hereof", "herein", or words
of like import, and each reference to the Credit Agreement in any Loan Document
shall be deemed a reference to the Credit Agreement as amended hereby. This
Amendment shall constitute a "Loan Document" for all purposes of the Credit
Agreement and the other Loan Documents.

         SECTION 5. Costs and Expenses. The Borrower agrees to reimburse the
Administrative Agent for its reasonable out of pocket expenses in connection
with this Amendment, including the reasonable fees, charges and disbursements of
counsel for the Administrative Agent.

         SECTION 6. Indemnity. It is agreed that for all purposes of Section
9.03(b) of the Credit Agreement, the execution, delivery and performance of this
Amendment and the other transactions contemplated hereby shall all be deemed to
be transactions contemplated by the Credit Agreement.

         SECTION 7. 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.
Delivery of any executed counterpart of a signature page of this Amendment by
facsimile transmission shall be as effective as delivery of a manually executed
counterpart hereof.

         SECTION 8. Applicable Law. THIS AMENDMENT SHALL BE CONSTRUED IN
ACCORDANCE WITH AND GOVERNED BY THE LAW OF THE STATE OF NEW YORK.


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         SECTION 9. Headings. The headings of this Amendment are for purposes of
reference only and shall not limit or otherwise affect the meaning hereof.


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

                                      LAND O'LAKES, INC.,

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


                                      JPMORGAN CHASE BANK, N.A.,
                                      individually, as Administrative Agent, and
                                      as Collateral Agent,

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


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                                                               SIGNATURE PAGE TO
                                                        SEVENTH AMENDMENT TO THE
                                                   LAND O'LAKES CREDIT AGREEMENT
                                        DATED AS OF OCTOBER 11, 2001, AS AMENDED


To approve Seventh Amendment to the
Credit Agreement:

Name of Institution:




   -----------------------------------


by
   -----------------------------------
   Name:
   Title: