Exhibit 10.31.1

               AMENDMENT NUMBER ONE TO LOAN AND SECURITY AGREEMENT

      THIS  AMENDMENT   NUMBER  ONE  TO  LOAN  AND  SECURITY   AGREEMENT   (this
"Amendment"), dated as of November 14, 2003, is entered into by and among PHIBRO
ANIMAL HEALTH  CORPORATION,  a New York  corporation  ("Parent"),  PHIBRO ANIMAL
HEALTH U.S.,  INC.,  a Delaware  corporation  ("PAHUS"),  PHIBRO  ANIMAL  HEALTH
HOLDINGS, INC., a Delaware corporation ("Holdings"),  PRINCE AGRIPRODUCTS, INC.,
a Delaware  corporation  ("Prince"),  PHIBRO-TECH,  INC.  ("PTI";  together with
Parent,  PAHUS, and Holdings,  the  "Borrowers"),  the lenders from time to time
party to the Loan and Security  Agreement  referenced below (each a "Lender" and
collectively,   the  "Lenders"),   WELLS  FARGO  FOOTHILL,  INC.,  a  California
corporation,  as the arranger and administrative agent for the Lenders ("Agent";
and together with the Lenders, collectively the "Lender Group"), in light of the
following:

                               W I T N E S S E T H

      WHEREAS,  Borrowers  and the Lender Group are parties to that certain Loan
and  Security  Agreement,  dated as of October 21, 2003 (as  amended,  restated,
supplemented, or otherwise modified from time to time, the "Loan Agreement");

      WHEREAS,  Borrowers  have  requested  that the Lender  Group  increase the
Maximum  Revolver  Amount  from  $15,000,000  to  $25,000,000   under  the  Loan
Agreement; and

      WHEREAS,  subject to the satisfaction of the conditions and upon the terms
set forth herein, the Lender Group is willing to do so.

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

1. DEFINITIONS  Capitalized  terms used herein and not otherwise  defined herein
shall  have the  meanings  ascribed  to them in the Loan  Agreement,  as amended
hereby.

2. AMENDMENT TO LOAN AGREEMENT

      (a)  Section  1.1 of the Loan  Agreement  is hereby  amended by adding the
following definition in alphabetical order:

            ""TTM EBITDA" means, as of any date of determination,  the EBITDA of
      Parent and its  Subsidiaries for the 12 month period ended as of such date
      of determination."

      (b) Section 1.1 of the Loan  Agreement  is hereby  amended by deleting the
definitions of "EBITDA",  "Indenture Securities",  and "Maximum Revolver Amount"
and replacing them with the following definitions:


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            ""EBITDA" means, with respect to any fiscal period, consolidated net
      earnings (or loss), minus  extraordinary  gains and interest income,  plus
      interest expense, income taxes,  depreciation and amortization,  and those
      charges which are both  nonrecurring  and noncash charges for such period,
      as determined in accordance with GAAP."

            ""Indenture  Securities"  means (a) the 105,000  Units (the "Units")
      issued by the Parent and the Foreign Issuer pursuant to the New Indenture,
      consisting  of  $85,000,000  aggregate  principal  amount of 13.0%  Senior
      Secured Notes due 2007 issued by the Parent (the "New Domestic Notes") and
      $20,000,000  aggregate  principal amount of 13.0% Senior Secured Notes due
      2007 issued by the Foreign Issuer (the "New Foreign  Notes" and,  together
      with the Domestic  Notes,  the "Notes") and (b) any units or notes, as the
      case may be,  that may be  issued  by the  Parent  or the  Foreign  Issuer
      pursuant to the New Indenture in exchange therefor."

            ""Maximum Revolver Amount" means up to $25,000,000."

      (c) Section 2.2 of the Loan  Agreement is hereby amended by deleting it in
its entirety and replacing it with the following:

      "2.2 Increase in the Maximum Revolver  Amount.  At any time within 90 days
      after the  Closing  Date,  upon 5 Business  Days prior  written  notice by
      Administrative Borrower to Agent, Borrowers may request an increase in the
      Maximum Revolver Amount from $25,000,000 up to $40,000,000. Subject to the
      foregoing,  and so long as no Default or Event of Default has occurred and
      is continuing as of the proposed date of such  increase,  so long as Agent
      has completed all of its legal,  business,  and  collateral  due diligence
      with  respect to  Borrowers  and  Guarantors,  so long as WFF has obtained
      credit committee  approval for the increase in the Maximum Revolver Amount
      for amounts in excess of $25,000,000  (it being  expressly  understood and
      agreed  that,  as of the date of this  Amendment,  WFF does not have  such
      credit approval and has made no commitments or assurances that such credit
      approval will be forthcoming),  and so long as the increase in the Maximum
      Revolver  Amount does not  contravene  the  Existing  Indenture or the New
      Indenture,  the Agent may  increase  the  Maximum  Revolver  Amount by the
      amount  requested by  Administrative  Borrower on the date of the proposed
      increase.  Borrowers  acknowledge and agree that the Applicable Prepayment
      Premium  and the  unused  line fee set  forth in the Fee  Letter  are each
      calculated by reference to the Maximum  Revolver Amount and an increase in
      the amount thereof pursuant hereto will have the effect of increasing such
      fee. The increase in the


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<PAGE>

      Maximum  Revolver  Amount  pursuant to this Section 2.2 shall increase the
      Revolving Commitment of each Lender proportionately in accordance with its
      Pro Rata Share thereof."

      (d)  Section  2.4 of the Loan  Agreement  is hereby  amended by adding the
following subsections (c) and (d)

            "(c)  Beginning on December 31, 2003,  immediately  at any time that
      the Revolver  Usage exceeds 1.5  multiplied  by TTM EBITDA,  measured on a
      month-end basis, Borrower shall prepay the Advances and cash collateralize
      the Letters of Credit in an amount equal to such excess in accordance with
      Section 2.4(d) of this Agreement.

            (d) Each prepayment  under Section 2.4(c) shall be remitted to Agent
      and all  such  payments  shall  be  applied  as  follows:  (i)  first,  to
      outstanding  Advances  until  paid  in  full  and  (ii)  second,  to  cash
      collateralize the Letters of Credit in an amount equal to 105% of the then
      extant Letters of Credit until paid in full."

      (e)  Section  3.2 of the Loan  Agreement  is hereby  amended  by  deleting
subsections (i), (k), (l), and (m) and replacing them with the following:

            "(i) within 45 days of the Closing  Date,  Agent shall have received
      Collateral  Access  Agreements with respect to: (i) One Parker Plaza, Fort
      Lee, NJ 07024, (ii) 8851 Dice Road, Santa Fe Springs,  CA 90670, (iii) One
      Prince Plaza,  Quincy,  Illinois 62301,  and (iv) 710 Route 46 East, Suite
      401, Fairfield, NJ 07004;

            (k) within 30 days of the Closing Date, Agent shall have received an
      updated Schedule 5.18 which shall include  information  regarding  Deposit
      Accounts and Securities Accounts of Borrowers' Foreign Subsidiaries."

      (f)  Section  3.2 of the Loan  Agreement  is hereby  amended by adding the
following subsections (n), (o), (p), (q), (r), (s), (t), and (u):

            "(n) Within 30 days of the Closing  Date,  Agent shall have received
      confirmation  that  appropriate   financing  statements   respecting  each
      Borrower and each Guarantor have been duly filed in such office or offices
      as may be necessary or, in the opinion of Agent,  desirable to perfect the
      Agent's Liens in and to the Collateral;

            (o) Within 30 days of the Closing  Date,  Agent shall have  received
      confirmation  that  appropriate  UCC-3  terminations


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<PAGE>

      statements  have been  filed  for all  financing  statements  filed by the
      Existing Lender against the Borrowers and the Guarantors;

            (p) Within 30 days of the Closing  Date,  Agent shall have  received
      copies of (i) the Phibro-Tech  3-year supply  agreement with Arch Chemical
      and (ii) the NuFarm long-term agreement;

            (q) Within 5 days after the  closing of the PMC Sales  Transactions,
      or no later than January 5, 2004,  Agent shall have received copies of the
      Prince Agriproducts/PMC agreements relating to the PMC Sales Transactions;

            (r) Within 60 days of the Closing  Date,  Agent shall have  received
      confirmation that Borrowers and their Domestic  Subsidiaries have made the
      appropriate  filings with the United States Patent and Trademark Office to
      register  any  patents and  trademarks  acquired  by  Borrowers  and their
      Domestic  Subsidiaries  from Pfizer (other than by license) in the name of
      Borrowers and their Domestic Subsidiaries;

            (s) Within 60 days of the Closing  Date,  Agent shall have  received
      the original Stock  certificates  for all Foreign  Subsidiaries  organized
      under   jurisdictions   that  have  stock  certificates  or  other  equity
      instruments reflecting the equity ownership of such Foreign Subsidiary and
      whose  interests  were  pledged  to Agent  pursuant  to the  Stock  Pledge
      Agreement;

            (t) Within 60 days of the Closing  Date,  Agent shall have  received
      confirmation that PMC and Prince  Agriproducts have separated all of their
      bank accounts; and

            (u) Within 45 days of the Closing  Date,  Agent shall have  received
      intercompany notes  representing all intercompany  indebtedness due to any
      Borrower or any Domestic Subsidiary, and the same shall have been endorsed
      to Agent."

      (g) Section 5.21 of the Loan  Agreement is hereby  deleted and replaced in
its entirety with the following:

      "5.21  Inactive  Subsidiaries.  Western  Magnesium  Corp. has no assets or
      liabilities and conducts no business activities other than its 1% interest
      in First Dice Road Company"

      (h) The Loan Agreement is hereby  amended by adding the following  Section
5.23:

      "5.23 Letters of Credit. Except for letters of credit and letter of credit
      undertakings  issued  for  Indenture  Purposes  and  letters of


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<PAGE>

      credit and letter of credit undertakings for purposes other than Indenture
      Purposes in the maximum  aggregate stated amount of $5,000,000,  there are
      no outstanding  letters of credit or letter of credit  undertakings issued
      for the account of Parent, any Borrower,  or any Subsidiary of Parent, and
      none  of  Parent,  any  Borrower,  or any  Subsidiary  of  Parent  has any
      reimbursement  obligations with respect to any letters of credit or letter
      of credit undertakings."

      (i)  Section  7.18 of the Loan  Agreement  is hereby  amended by  deleting
subsection (c) in its entirety and replacing it with the following:

      "(c)  Determination  of  Future  Levels.  Agent  shall,  in its  Permitted
      Discretion,  establish the monthly minimum EBITDA and capital expenditures
      covenants for the 10 month period ended July 31, 2004, the 11 month period
      ended August 31, 2004,  and the 12 month period ended  September 30, 2004,
      and for each  trailing 12 month period  thereafter  based upon  Borrowers'
      Projections  for such fiscal year delivered  pursuant to Section 6.3(c) of
      this  Agreement,  which  Borrowers'  Projections  shall be satisfactory to
      Agent in all  respects.  Borrowers  shall  execute any  amendment  to this
      Section 7.18 requested by Agent to document the inclusion of such covenant
      levels.  If Borrowers fail to timely  deliver the  Borrowers'  Projections
      pursuant to Section  6.3(c),  the EBITDA level for (i) the 10 month period
      ended July 31, 2004, the 11 month period ended August 31, 2004, and the 12
      month period  ended  September  30,  2004,  shall be measured on a monthly
      basis at an amount  equal to 110% of the most recent prior period and (ii)
      each succeeding trailing 12 month period after September 30, 2004 shall be
      measured  on a  monthly  basis  at an  amount  equal  to 100% of the  last
      trailing 12 months."

      (j) The Loan Agreement is hereby  amended by adding the following  Section
7.19:

      "7.19  Letters  of Credit.  Request  or obtain  any  Letters of Credit for
      purposes other than Indenture Purposes;  provided however,  that Borrowers
      may request and obtain Letters of Credit for purposes other than Indenture
      Purposes under this Agreement up to a maximum  aggregate  stated amount of
      $5,000,000 less the aggregate of the face amount of all undrawn letters of
      credit and letter of credit  undertakings issued for the account of Parent
      or any of its Subsidiaries and all reimbursement obligations of Parent and
      its Subsidiaries in connection therewith (in each case, other than letters
      of  credit  or  letter  of  credit   undertakings   issued  for  Indenture
      Purposes)."

      (k) Schedule C-1 to the Loan  Agreement is hereby  deleted in its entirety
and  replaced  with the  attached  Exhibit A.


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<PAGE>

3.  CONDITIONS  PRECEDENT TO THIS  AMENDMENT.  The  satisfaction  of each of the
following shall  constitute  conditions  precedent to the  effectiveness of this
Amendment and each and every provision hereof:

      (a) Agent shall have received this Amendment, duly executed by the parties
hereto, and the same shall be in full force and effect;

      (b) Agent shall have received the opinions of Borrowers'  counsel required
by Section 3.1(m) of the Loan  Agreement,  the form and substance of which shall
be satisfactory to Agent;

      (c) Agent  shall  have  received  the  reaffirmation  and  consent of each
Guarantor,  attached  hereto as Exhibit B, duly  executed  and  delivered  by an
authorized official of such Guarantor;

      (d) The representations and warranties in the Loan Agreement and the other
Loan Documents  shall be true and correct in all material  respects on and as of
the date  hereof,  as though  made on such date  (except to the extent that such
representations and warranties relate solely to an earlier date), and except for
changes permitted by the Loan Documents;

      (e) No Default or Event of Default  shall have  occurred and be continuing
on the date hereof or as of the date of the effectiveness of this Amendment; and

      (f) No injunction,  writ,  restraining order, or other order of any nature
prohibiting,  directly  or  indirectly,  the  consummation  of the  transactions
contemplated  herein  shall  have  been  issued  and  remain  in  force  by  any
Governmental Authority against Borrowers, Guarantors, or the Lender Group.

4.  GOVERNING  LAW.  THIS  AMENDMENT  SHALL BE  GOVERNED  BY, AND  CONSTRUED  IN
ACCORDANCE  WITH, THE LAW OF THE STATE OF NEW YORK  APPLICABLE TO CONTRACTS MADE
AND TO BE PERFORMED IN THE STATE OF NEW YORK.

5. ENTIRE  AMENDMENT;  EFFECT OF AMENDMENT.  This  Amendment,  and the terms and
provisions hereof,  constitute the entire agreement among the parties pertaining
to the subject matter hereof and supersedes any and all prior or contemporaneous
amendments  relating to the subject matter hereof.  Except for the amendments to
the Loan Agreement  expressly set forth in Section 4 hereof,  the Loan Agreement
and other Loan Documents shall remain unchanged and in full force and effect. To
the extent any terms or provisions of this Amendment  conflict with those of the
Loan  Agreement  or other  Loan  Documents,  the  terms and  provisions  of this
Amendment shall control. This Amendment is a Loan Document.  Except as expressly
set forth herein,  the execution,  delivery,  and  performance of this Amendment
shall not operate as a waiver of or as an  amendment  of, any right,  power,  or
remedy of the Lender Group as in effect prior to the date hereof. The agreements
set forth  herein are  limited  to the  specifics  hereof,  shall not apply with
respect  to any  facts or  occurrences  other  than  those on which the same are
based,  shall not excuse future  non-compliance  under the Loan  Agreement,  and
shall not  operate as a consent to any further or other  matter,  under the Loan
Documents.


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<PAGE>

6. COUNTERPARTS;  TELEFACSIMILE EXECUTION. This Amendment may be executed in any
number of counterparts, all of which taken together shall constitute one and the
same  instrument  and any of the parties  hereto may execute  this  Amendment by
signing  any such  counterpart.  Delivery  of an  executed  counterpart  of this
Amendment  by  telefacsimile  shall be equally as  effective  as  delivery of an
original  executed  counterpart  of this  Amendment.  Any  party  delivering  an
executed  counterpart of this Amendment by  telefacsimile  also shall deliver an
original executed  counterpart of this Amendment,  but the failure to deliver an
original executed counterpart shall not affect the validity, enforceability, and
binding effect of this Amendment.

7. MISCELLANEOUS.

      (a) Upon the  effectiveness of this Amendment,  each reference in the Loan
Agreement to "this Agreement",  "hereunder", "herein", "hereof" or words of like
import  referring  to the  Loan  Agreement  shall  mean  and  refer  to the Loan
Agreement as amended by this Amendment.

      (b) Upon the  effectiveness of this Amendment,  each reference in the Loan
Documents to the "Loan Agreement",  "thereunder",  "therein", "thereof" or words
of like import  referring to the Loan Agreement shall mean and refer to the Loan
Agreement as amended by this Amendment.

                            [Signature page follows.]


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<PAGE>

      IN WITNESS WHEREOF,  the parties have caused this Amendment to be executed
and delivered as of the date first written above.

                                            PHIBRO ANIMAL HEALTH CORPORATION,
                                            a New York corporation

                                            By: /s/ Richard G. Johnson
                                                --------------------------------
                                                Title: Vice President
                                                & Chief Financial Officer

                                            PHIBRO ANIMAL HEALTH U.S., INC.,
                                            a Delaware corporation

                                            By: /s/ David C. Storbeck
                                                --------------------------------
                                                Title: Vice President

                                            PHIBRO ANIMAL HEALTH HOLDINGS, INC.,
                                            a Delaware corporation

                                            By: /s/ David C. Storbeck
                                                --------------------------------
                                                Title: Vice President

                                            PRINCE AGRIPRODUCTS, INC.,
                                            a Delaware corporation

                                            By: /s/ David C. Storbeck
                                                --------------------------------
                                                Title: Vice President

                                            PHIBRO-TECH, INC.,
                                            a Delaware corporation

                                            By: /s/ David C. Storbeck
                                                --------------------------------
                                                Title: Vice President


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<PAGE>

                                            WELLS FARGO FOOTHILL, INC.,
                                            a California  corporation, as Agent

                                            By: /s/ Renee D. Lefebvre
                                                --------------------------------
                                                Title: VP

                                    Exhibit A

                                  Schedule C-1
                                   Commitments

================================================================================
         Lender                   Revolver Commitment           Total Commitment
================================================================================
Wells Fargo Foothill, Inc.            $25,000,000                 $25,000,000
================================================================================

================================================================================

================================================================================

================================================================================
All Lenders                           $25,000,000                 $25,000,000
================================================================================


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<PAGE>

                                    Exhibit B

                            REAFFIRMATION AND CONSENT

      All capitalized  terms used herein but not otherwise  defined herein shall
have the meanings  ascribed to them in that certain AMENDMENT NUMBER ONE TO LOAN
AND SECURITY  AGREEMENT  (the  "Amendment"),  dated as of November 14, 2003. The
undersigned each hereby (a) represents and warrants to the Lender Group that the
execution,  delivery,  and  performance  of this  Reaffirmation  and Consent are
within  its  corporate  powers,  have  been  duly  authorized  by all  necessary
corporate action,  and are not in contravention of any law, rule, or regulation,
or any order, judgment,  decree, writ,  injunction,  or award of any arbitrator,
court, or governmental  authority,  or of the terms of its charter or bylaws, or
of any material  contract or  undertaking to which it is a party or by which any
of its  properties  may be bound or  affected;  (b)  consents to the  execution,
delivery,  and performance of the Amendment;  (c) acknowledges and reaffirms its
obligations  owing to the Lender Group under the Loan Documents to which it is a
party;  and (d) agrees that each of the Loan Documents to which it is a party is
and shall remain in full force and effect in accordance  with the terms thereof.
Although the  undersigned  has been informed of the matters set forth herein and
has acknowledged and agreed to same, it understands that the Lender Group has no
obligations  to  inform  it of  such  matters  in  the  future  or to  seek  its
acknowledgement  or  agreement  to future  consents or  amendments,  and nothing
herein shall  create such a duty.  Delivery of an executed  counterpart  of this
Reaffirmation  and Consent by  telefacsimile  shall be equally as  effective  as
delivery of an original executed  counterpart of this Reaffirmation and Consent.
Any party delivering an executed  counterpart of this  Reaffirmation and Consent
by  telefacsimile  also shall deliver an original  executed  counterpart of this
Reaffirmation  and  Consent  but the  failure to deliver  an  original  executed
counterpart shall not affect the validity, enforceability, and binding effect of
this Reaffirmation and Consent. This Reaffirmation and Consent shall be governed
by the laws of the State of New York.

                            [Signature page follows.]

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<PAGE>

                                                        S-1

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

                                            PhibroChem, Inc., a New Jersey
                                            corporation

                                            By: /s/ David C. Storbeck
                                                --------------------------------
                                                Name: David C. Storbeck
                                                Title: Vice President

                                            Western Magnesium Corp., a
                                            California corporation

                                            By: /s/ David C. Storbeck
                                                --------------------------------
                                                Name: David C. Storbeck
                                                Title: Vice President

                                            CP Chemicals, Inc., a New Jersey
                                            corporation

                                            By: /s/ David C. Storbeck
                                                --------------------------------
                                                Name: David C. Storbeck
                                                Title: Vice President

                                            PHIBRO CHEMICALS, INC., a New York
                                            corporation

                                            By: /s/ David C. Storbeck
                                                --------------------------------
                                                Name: David C. Storbeck
                                                Title: Vice President