<PAGE>

                               VIRBAC CORPORATION
                                    FORM 10-Q
                               SEPTEMBER 30, 2003

Exhibit 10.15

Secured Subordinated Promissory Note for $4,000,000 by and among Virbac
Corporation, PM Resources, Inc., St. JON Laboratories, Inc., Francodex
Laboratories, Inc., Virbac AH, Inc., Delmarva Laboratories, Inc., and Virbac,
S.A., dated April 29, 2004.

<PAGE>

      THIS NOTE HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED ("THE SECURITIES ACT"), OR ANY APPLICABLE STATE SECURITIES LAWS. THIS
NOTE HAS BEEN ACQUIRED FOR INVESTMENT AND NO INTEREST HEREIN MAY BE SOLD,
DISTRIBUTED, ASSIGNED, OFFERED, PLEDGED OR OTHERWISE TRANSFERRED UNLESS (A)
THERE IS AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT AND
APPLICABLE STATE SECURITIES LAWS COVERING ANY SUCH TRANSACTION INVOLVING THIS
NOTE, (B) THE BORROWERS RECEIVE AN OPINION OF LEGAL COUNSEL ADDRESSED TO THE
HOLDER OF THIS NOTE (CONCURRED IN BY LEGAL COUNSEL FOR THE HOLDER) STATING THAT
SUCH TRANSACTION IS EXEMPT FROM REGISTRATION, OR (C) THE BORROWERS ARE OTHERWISE
SATISFIED THAT SUCH TRANSACTION IS EXEMPT FROM REGISTRATION.

      THIS NOTE IS SUBJECT TO A SUBORDINATION AGREEMENT IN FAVOR OF FIRST BANK
DATED AS OF APRIL 9, 2004.

April 29, 2004                                                     $4,000,000.00

                               VIRBAC CORPORATION
                      SECURED SUBORDINATED PROMISSORY NOTE

      FOR VALUE RECEIVED, Virbac Corporation, a Delaware corporation (the
"Company"), PM Resources, Inc., a Missouri corporation ("PM"), St. Jon
Laboratories, Inc., a California corporation ("St. Jon"), Francodex
Laboratories, Inc., a Kansas corporation ("Francodex"), Delmarva Laboratories,
Inc., a Virginia corporation ("Delmarva") and Virbac AH, Inc., a Delaware
corporation ("AH", with Virbac , PM, St. Jon, Francodex, Delmarva and AH being
hereafter sometimes referred to individually as a "Borrower" and collectively as
the "Borrowers"), hereby promise to pay to the order of Virbac S. A. or its
registered assigns (the "Holder"), the maximum aggregate principal sum of Four
Million Dollars ($4,000,000.00) or such lesser amount of any loans made by
Holder to Borrowers as recorded on the books and records of Holder, together
with interest thereon at the rate(s) set forth in Section 1 below. This Secured
Subordinated Promissory Note (this "Note") shall be subordinate to the
indebtedness (the "Senior Indebtedness") of Borrowers under that certain Credit
Agreement, dated September 7, 1999, as previously amended, most recently by the
Seventh Amendment, dated March 1, 2004, and as the same may be further amended
hereafter (the "Credit Agreement") and the obligation of Borrowers to repay the
principal and interest due to the Holder under this Note shall be secured by a
collateral pledge of all the current and future assets of Borrowers pursuant to
the Amended and Restated Security Agreement, dated of even date herewith,
entered into by Borrowers and the Holder named therein (the "Security
Agreement"), which lien shall be subordinate to any lien granted by Borrowers to
secure payment of the Senior Indebtedness pursuant to the terms of the
Subordination Agreement entered into by the Holder in favor of First Bank, dated
of even date herewith. This Note shall rank pari passu with that certain Secured
Subordinated Promissory Note by Borrowers in favor of Holder, dated as of April
9, 2004, in the amount of $3,000,000.00 (the "April Note"). The April Note,
together with this Note, shall be

<PAGE>

referred to collectively herein as the "Notes." Upon payment in full of all
principal and interest payable hereunder, this Note shall be surrendered to the
Borrowers for cancellation.

      At any time it is requesting a loan, the Company shall give written or
telecopy notice to Holder, which notice shall be irrevocable and shall be given
by no later than 9:00 a.m. (Central Time) four days prior to the date it
requests that Holder make a loan hereunder. Each such notice shall specify the
date the loan is requested (which shall be a business day) and the dollar amount
of such loan. Holder shall use commercially reasonable efforts to provide
currently available cash to Borrowers on the date specified in Borrowers'
request but shall not be liable to Borrowers or any other person if it fails to
provide currently available cash to Borrowers on or before the close of business
on the specified date if such failure is a result of the process and procedures
necessary to transfer cash balances across international borders.

      The following is a statement of the rights of the Holder and the
conditions to which this Note is subject, and to which the Holder, by the
acceptance of this Note, agrees:

1.    Calculation of Interest.

      (a) From the date hereof until all of Borrowers' obligations under this
Note have been fully satisfied, the principal outstanding under this Note from
time to time shall bear interest on a basis of a 360-day year for the actual
number of days amounts are outstanding hereunder, at a variable rate initially
equal to five and one half percent (5.5%) per annum (the "Base Rate") as
adjusted in accordance with the provisions of subsection (b) below (such rate,
as adjusted, the "Adjusted Rate").

      (b) On the first day of each calendar month beginning with June 1, 2004
(each such day an "Interest Rate Adjustment Date"), the interest rate to be
charged against the outstanding principal balance for the remainder of that
calendar month will be recalculated by adding to the Base Rate such amount equal
to the higher of (i) the amount by which the Current One Month LIBOR US Dollar
Rate exceeds the LIBOR Reference Rate or (ii) the amount that the Current One
Month EURIBOR Rate exceeds the EURIBOR Reference Rate, provided, however, that:

            (i)   No adjustment shall be made to the Base Rate on any Interest
                  Rate Adjustment Date prior to the first Interest Rate
                  Adjustment Date until either the Current One Month LIBOR US
                  Dollar Rate exceeds the LIBOR Reference Rate or the Current
                  One Month EURIBOR Rate exceeds the EURIBOR Reference Rate,
                  respectively, by more than 50 basis points (0.5%); thereafter,
                  the Adjusted Rate will be adjusted on each Interest Rate
                  Adjustment Date as set forth in the first paragraph of this
                  Section 1(b); and

            (ii)  Although the Adjusted Rate may decrease following any decrease
                  in the one month LIBOR Spot Rate or Current One Month EURIBOR
                  Rate, it shall not be adjusted below five and one half percent
                  (5.5%) per annum.

      (c) For purposes of the forgoing:

                                       2
<PAGE>

If an Event of Default (other than an Event of Default specified in Section 3(c)
or Section 3(d) hereof) occurs and is continuing, then the Holder may declare
the outstanding principal amount and any accrued interest on this Note and all
other payments payable hereunder to be forthwith due and payable immediately,
without presentment, demand, protest or further notice of any kind, all of which
are hereby expressly waived by Borrower, to the fullest extent permitted by
applicable law. If an Event of Default specified in Section 3(c) or Section 3(d)
hereof occurs and is continuing, then the outstanding principal amount and any
accrued interest on this Note and all other payments payable hereunder shall
become and be immediately due and payable without any declaration or other act
on the part of the Holder, and the Holder may take all actions or exercise
remedies provided for pursuant to the Security Agreement, or otherwise, with
respect to the pledged Collateral (as defined in the Security Agreement). The
Holder by notice to the Company may rescind an acceleration and its consequences
if the rescission would not conflict with any judgment or decree and if all
existing Events of Default have been cured or waived, other than nonpayment of
principal or interest that has become due solely because of such acceleration.
No such rescission shall affect any subsequent default or impair any right
thereto.

4.    Miscellaneous.

      (a) Usury. It is the express intent of the Borrowers and the Holder hereto
that the payment of all or any portion of the outstanding principal amount of
and accrued interest under this Note be exempt from the application of any
applicable usury or similar laws under any state, federal or foreign
jurisdiction. Each of the Borrowers hereby irrevocably waive, to the fullest
extent permitted by law, any objection or defense which any Borrower, may now or
hereafter have to the payment when due of any and all Note principal or accrued
interest arising out of or relating to a claim of usury or similar laws and each
of the Borrowers hereby agrees that neither it nor any of its affiliates shall
in the future bring, commence, maintain, prosecute or voluntarily aid in any
action at law, proceeding in equity or other legal proceeding against the Holder
based on a claim that Borrowers' payment obligations under this Note violate the
usury or similar laws of any state, federal or foreign jurisdiction.
Notwithstanding the foregoing, in the event any interest is paid on this Note
which is deemed to be in excess of the then legal maximum rate, then that
portion of the interest payment representing an amount in excess of the then
legal maximum rate shall be deemed a payment of principal and applied against
the principal amount due under this Note.

      (b) Expenses. Borrowers agree to pay all costs of collection, including
reasonable attorneys' fees, incurred by the Holder in collecting or enforcing
this Note. The Borrowers agree to pay Holder upon demand, the amount of any and
all expenses, including fees, expenses and disbursements of Holder's counsel and
of any other expert or agent acting on Holders behalf, that Holder may incur in
collecting or enforcing this Note or in exercising rights under the Security
Agreement or the Subordination Agreement. Notwithstanding the forgoing, any
expense incurred by Holder as provided above shall be treated as an advance of
principal pursuant to this Note and shall bear interest at the then applicable
rate from the date such expense was incurred by Holder until the date paid by
the Borrowers.

      (c) Waiver. Any provision of this Note may be amended, waived or modified
upon the written consent of Borrowers and the Holder. A waiver or consent given
hereunder shall be

                                       5
<PAGE>

effective only if in writing and in the specific instance and for the specific
purpose for which given.

      (d) Severability. In case any provision of this Note is deemed to be
invalid, illegal or unenforceable, the validity, legality and enforceability of
the remaining provisions will not in any way be affected or impaired thereby.

      (e) Governing Law. This Note shall be governed by and construed in
accordance with the laws of the State of Delaware without regard to the
conflicts of law principles thereof.

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<PAGE>

      IN WITNESS WHEREOF, the undersigned has caused this Note to be duly
executed and delivered by its proper and duly authorized officer as of the date
first written above.

                                              VIRBAC CORPORATION

                                              By: /s/ David Eller
                                                  -------------------------
                                              Name: David Eller
                                              Title: President

                                              PM RESOURCES, INC.

                                              By: /s/ David Eller
                                                  -------------------------
                                              Name: David Eller
                                              Title: President

                                              ST. JON LABORATORIES, INC.

                                              By: /s/ David Eller
                                                  -------------------------
                                              Name: David Eller
                                              Title: President

                                              FRANCODEX CORPORATION, INC.

                                              By: /s/ David Eller
                                                  -------------------------
                                              Name: David Eller
                                              Title: President

                                              DELMARVA CORPORATION, INC.

                                              By: /s/ David Eller
                                                  -------------------------
                                              Name: David Eller
                                              Title: President

                                              VIRBAC AH, INC.

                                              By: /s/ David Eller
                                                  -------------------------
                                              Name: David Eller
                                              Title: President

                                       7
<PAGE>

                     AMENDED AND RESTATED SECURITY AGREEMENT

      This Amended and Restated Security Agreement (hereinafter referred to as
this "Security Agreement") is made and entered into as of the 29th day of April,
2004, by and between Virbac Corporation, a Delaware corporation ("Virbac"), PM
Resources, Inc., a Missouri corporation ("PM"), St. Jon Laboratories, Inc. a
California corporation ("St. Jon"), Francodex Laboratories, Inc., a Kansas
corporation ("Francodex"), Delmarva Laboratories, Inc., a Virginia corporation
("Delmarva"), Virbac AH, Inc., a Delaware corporation("AH", with Virbac, PM, St.
Jon, Francodex, Delmarva and AH being hereafter sometimes referred to
individually as a "Borrower" and collectively as the "Borrowers"), and Virbac S.
A., a corporation organized under the laws of the Republic of France (the
"Secured Party").

                                R E C I T A L S:

      WHEREAS, the Borrowers and the Secured Party entered into that certain
Security Agreement dated as of April 9, 2004 (the "Prior Agreement"), in
connection with the loan made by Virbac S.A. to the Borrowers in the amount of
$3,000,000.00;

      WHEREAS, the parties desire to amend and restate the Prior Agreement to
allow Virbac S.A. to make additional loans to the Borrowers in accordance with
the terms and conditions set forth herein and in the Notes (as defined below);

      WHEREAS, Virbac is in need of additional capital to fund working capital
and for other general corporate purposes;

      WHEREAS, in order to allow Virbac to meet its near-term capital
requirements, Secured Party is willing to make various loans to Virbac on the
terms and conditions agreed to by the parties; and

      WHEREAS, it is a condition to Secured Party's willingness to advance any
funds to Borrowers pursuant to the Notes or otherwise that the Borrowers enter
into this Security Agreement.

      NOW, THEREFORE, in consideration of the foregoing, the mutual promises and
covenants hereinafter set forth, and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the parties hereto
agree as follows:

      1.    SECURITY INTEREST.

            (a) Borrowers hereby grant to Secured Party, for its benefit, a
      continuing security interest in, and do hereby collaterally assign,
      pledge, mortgage, convey and set over unto Secured Party, for its benefit,
      the Collateral (as defined herein) and all of Borrowers' present and
      hereafter acquired right, title and interest in and to the Collateral, for
      the purpose of securing full and punctual payment of amounts due the
      Secured Party arising under or in connection with the Notes and the
      performance of all obligations, agreements, covenants, terms and
      conditions contained in the Notes and herein as well as any renewals,
      extensions, refinancings and restructurings of the Notes or any additional
      indebtedness which may be extended by Secured Party to Borrowers. For
      purposes

<PAGE>

      hereof, Collateral shall mean all of the assets of Borrowers, wherever
      located, whether presently owned or hereafter acquired, as more fully
      described on Exhibit A attached hereto. For the purposes of this Security
      Agreement, "Notes" shall mean: (i) that certain Secured Subordinated
      Promissory Note by Borrowers in favor of the Secured Party, dated as of
      April 9, 2004, in the amount of $3,000,000.00; (ii) that certain Secured
      Subordinated Promissory Note by Borrowers in favor of the Secured Party,
      dated even herewith, in the amount of $4,000,000.00; and (iii) any other
      secured subordinated promissory notes evidencing obligations to repay
      funds by the Borrowers in favor of the Secured Party, after the date
      hereof.

            (b) The Secured Party shall have a second priority security interest
      in and to the Collateral subordinate only to the security interest and
      rights granted pursuant to that certain Credit Agreement, dated September
      7, 1999, as previously amended, most recently by the Seventh Amendment,
      dated March 1, 2004, and as the same may be hereafter amended (the "Credit
      Agreement"). The indebtedness evidenced by the Credit Agreement is
      hereinafter referred to as the "Senior Indebtedness" and the party who
      has, or parties who have, advanced funds to Borrowers pursuant to the
      Credit Agreement as hereinafter referred to both individually and
      collectively as the "Senior Lender". The rights and priorities of Secured
      Party and Senior Lender with respect to the Collateral are more fully set
      forth in that certain Subordination Agreement dated of even date herewith,
      entered into by Secured Party in favor of the Senior Lender (the
      "Subordination Agreement"). The security interests are granted as security
      only and shall not subject the Secured Party to, or transfer to the
      Secured Party, or in any way affect or modify, any obligation or liability
      of the Borrowers therewith.

      2. WARRANTIES, REPRESENTATIONS AND COVENANTS OF BORROWERS. Each of the
Borrowers hereby severally, not jointly, warrants, represents and covenants to
Secured Party as follows:

            (a) Each Borrower is a corporation duly organized, validly existing
      and in good standing under the laws of its respective jurisdiction of
      incorporation and is duly qualified or licensed to conduct business in
      each jurisdiction in which the nature of its business or its assets
      require such qualification or licensing under applicable law.

            (b) Borrowers are the sole owners of, and have good and marketable
      title to, each and any every part of Collateral, free from any lien,
      pledge, conditional sale contract, lease or other title retention
      agreement, security interest, encumbrance or any other adverse claim of
      any kind, except for the security interests granted to Senior Lender and
      to Secured Party hereunder. Borrowers will not permit any financing
      statement to be filed with respect to the Collateral or any portion
      thereof except in favor of Secured Party and Senior Lender.

            (c) The Collateral will not be used and was not purchased for
      personal, family or household purposes.

            (d) There is no legal, administrative or other proceeding pending
      or, to the best of Borrowers' knowledge, threatened against any Borrower
      or Borrowers' title to the

                                       2
<PAGE>

      Collateral or against Borrowers' grant of a security interest hereunder,
      nor do Borrowers know of any basis for the assertion of any such claim.

            (e) At the request of Secured Party, Borrowers have or will join
      Secured Party in executing one or more financing statements, in form
      satisfactory to Secured Party, identifying the Collateral and evidencing
      the security interest of Secured Party in the Collateral pursuant to the
      requirements of the Uniform Commercial Code in effect in Delaware from
      time to time (the "UCC"). Borrowers will pay the cost of filing the same
      or other suitable documents in all public offices wherever filing is
      deemed by Secured Party to be necessary or desirable. When the UCC
      financing statements and any other filings necessary to perfect the
      security interests granted hereby in appropriate form are filed with the
      appropriate offices, the security interests shall constitute valid and
      perfected security interests in all of the Collateral that may be
      perfected by such filings, subordinate to the liens and rights of Senior
      Lender but prior to all other liens and rights of others therein.

            (f) Except for sales of inventory permitted in the ordinary course
      of their businesses and consistent with past practices, without the prior
      written consent of Secured Party, Borrowers will not sell, exchange,
      dispose of, lease, offer to sell or otherwise transfer or otherwise deal
      with the Collateral or any portion or interest therein, unless
      simultaneously therewith new items of Collateral, which items may be
      similar to those proposed to be disposed of and which shall be of equal or
      greater value, are substituted therefor. All after-acquired property of
      Borrowers and all additions or replacements acquired pursuant to the
      provisions of this paragraph shall immediately be and become, without any
      other act on the part of Borrowers, subject to the security interest and
      lien created pursuant to this Security Agreement. If the Collateral or any
      part thereof is sold, transferred, exchanged, or otherwise disposed of,
      the security interest of Secured Party shall extend to the proceeds of
      such sale, transfer, exchange or other disposition.

            (g) Borrowers shall cause, as of the date hereof, and shall cause
      the Collateral at all times to be kept insured at their own expense under
      one or more policies, for such periods and amounts and against such risks
      and liabilities, and in such form as are in accordance with prudent
      industry practices. Borrowers will promptly notify Secured Party of any
      loss or damage to the Collateral and such insurance shall be for the full
      replacement value of the Collateral. In the event of foreclosure or sale
      under this Security Agreement, all right, title and interest of Borrowers
      in and to any insurance policies then in force shall pass to the purchaser
      at any such sale, and Secured Party is hereby appointed attorney-in-fact
      for Borrowers to assign and transfer said policies.

            (h) Borrowers will properly care for and keep the Collateral in good
      condition and repair and will not misuse, abuse, allow to deteriorate,
      waste or destroy the Collateral or any part thereof, except for reasonable
      wear and tear in the course of its normal and expected use.

                                       3
<PAGE>

            (i) With respect to Borrowers' use or ownership of the Collateral or
      the conduct of their respective businesses, Borrowers will not engage in
      any material violation of any law, statute or governmental rules,
      regulation or ordinance.

            (j) Borrowers will pay or cause to be paid all taxes and assessments
      assessed against the Collateral when the same become due and payable.

            (k) At Secured Party's request, Borrowers will, at their own
      expense, execute or procure any document, and do all other acts which from
      the character or use of the Collateral may be reasonably necessary to
      protect and defend the Collateral against any and all rights, claims or
      interests of third persons, and will otherwise preserve the Collateral as
      security hereunder.

            (l) Borrowers shall furnish promptly to Secured Party such
      information concerning the Collateral as Secured Party may from time to
      time request. Borrowers shall permit and hereby authorize Secured Party to
      examine and inspect the Collateral and any portion thereof wherever the
      same may be located and hereby grant Secured Party full access to, and the
      right to audit, any and all of any Borrowers' books and records pertaining
      to the Collateral for the purpose of verifying the value of Collateral.

            (m) Borrowers will promptly notify Secured Party of any change in
      the location of any Collateral or change in any of Borrowers' corporate
      names, trade names or their form of doing business.

      3. DEFAULT. If one or more of the events described in subsections (a)
through (g) of this Section 3 shall happen and be continuing, each of such
events shall be referred to as an "Event of Default":

            (a) Default shall be made by Borrowers (i) in the payment of
      principal of any of the Notes when and as the same shall become due and
      payable, whether at maturity thereof or otherwise, or (ii) in the payment
      of interest on any of the Notes when and as the same shall become due and
      payable in accordance with the provisions of the Notes; or

            (b) Default shall be made by Borrowers (i) in the performance or
      observance of any other of the covenants, conditions or agreements on the
      part of Borrowers, their respective successors or assigns, set forth
      herein or in the Notes, or (ii) by the existence or occurrence of any
      Event of Default as defined in the Notes; or

            (c) Borrowers fail to satisfy, in any material respect, or otherwise
      breach any representations, warranties or covenants contained herein or in
      the Notes; or

            (d) The occurrence and continuance of an event of default under the
      Credit Agreement by and among Borrowers and Senior Lender dated September
      7, 1999, as amended or any ancillary document thereto; or

            (e) A decree or order by a court having jurisdiction in the premises
      shall have been entered adjudging any of the Borrowers bankrupt or
      insolvent, or approving as properly filed a petition seeking
      reorganization, readjustment, arrangement, composition

                                       4
<PAGE>

      or similar relief for any of the Borrowers under the federal bankruptcy
      laws, or any other similar applicable federal or state law, and such
      decree or order shall have continued undischarged and unstayed for a
      period of 60 days; or a decree or order of a court having jurisdiction in
      the premises for the appointment of a receiver or liquidator or trustee or
      assignee in bankruptcy or insolvency of any of the Borrowers or a
      substantial part of the property of any of the Borrowers, or for the
      winding up or liquidation of its affairs, shall have been entered, and
      such decree or order shall have remained in force, undischarged and
      unstayed for a period of 60 days; or any property of any of the Borrowers
      shall be sequestered or attached and shall not be returned to the
      possession of any of the Borrowers or released from such attachment within
      60 days thereafter; or

            (f) Any of the Borrowers shall institute proceedings to be
      adjudicated a voluntary bankrupt, or insolvent or shall consent to the
      filing of a bankruptcy proceeding against it, or shall file a petition or
      answer or consent seeking reorganization, readjustment, arrangement,
      composition or similar relief under the federal bankruptcy laws, or any
      other similar applicable federal or state law, or shall consent to the
      filing of any such petition, or shall consent to the appointment of a
      receiver or liquidator or custodian or trustee or assignee in bankruptcy
      or insolvency of it or of a substantial part of its assets or admit its
      inability to pay its debts generally as they become due or the making by
      it of an assignment for the benefit of creditors, or corporate action
      shall be taken by any of Borrowers in furtherance of any of the aforesaid
      purposes; or

            (g) The occurrence of any deterioration, depreciation, destruction
      or impairment of the condition or value of the Collateral, or any part
      thereof, which causes the Collateral to become unsatisfactory to Secured
      Party as to its character or value.

Then, in any such case, Secured Party may upon further written notice from
Secured Party to Borrowers declare the aggregate principal amount of the Notes,
and all interest due or to become due, to be due and payable immediately,
without demand or notice and upon any such declaration the aggregate principal
amount of the Notes and said accrued interest shall be immediately due and
payable and, Secured Party may thereupon proceed to collect the same and to
protect and enforce Secured Party's rights either by suit in equity, or by
action at law, or by other appropriate proceedings whether for the specific
performance (to the extent permitted by law) or any covenant or agreement
contained herein or in the Notes or in aid of the exercise of any power granted
herein or in the Notes, and proceed to enforce the payment of the Notes and to
enforce any other legal or equitable right of Secured Party.

      4. REMEDIES. Subject to the rights of Senior Lender as set forth in the
Subordination Agreement, if any Event of Default shall have occurred and be
continuing Secured Party may:

            (a) Secured Party may sell or otherwise dispose of the Collateral as
      described in Section 5(e) below or exercise any of the rights conferred
      upon Secured Party under the Notes or hereunder without affecting in any
      way any other rights or remedies to which Secured Party may be entitled;

            (b) Make such payments and do such acts as Secured Party may deem
      necessary to protect its security interest in the Collateral, including
      without limitation,

                                       5
<PAGE>

      paying, purchasing, contesting or compromising any encumbrance, charge,
      claim or lien which is prior to or superior to the security interest
      granted hereunder, and, in exercising any such powers or authority, pay
      all expenses incurred in connection therewith, and all funds expended by
      Secured Party in protecting its security interest shall be deemed
      additional indebtedness secured by this Security Agreement;

            (c) For the purpose of enforcing any and all rights and remedies
      under this Security Agreement, Secured Party may (i) require Borrowers to,
      and each of Borrowers agrees that it will, upon the request of Secured
      Party, assemble all or any part of the Collateral as directed by Secured
      Party and make it available at a place designated by Secured Party which
      is, in Secured Party's opinion, reasonably convenient to Secured Party and
      Borrowers, whether at the premises of any of Borrowers or otherwise, (ii)
      to the extent permitted by applicable law, enter, with or without process
      of law and without breach of the peace, any premise where any such
      Collateral is or may be located and, without charge or liability to
      Secured Party, seize and remove such Collateral from such premises, (iii)
      have access to and use Borrowers' books and records, computers and
      software relating to the Collateral, and (iv) prior to the disposition of
      any of the Collateral, store or transfer such Collateral without charge in
      or by means of any storage or transportation facility owned or leased by
      Borrowers, process, repair or recondition such Collateral or otherwise
      prepare it for disposition in any manner and to the extent Secured Party
      deems appropriate and, in connection with such preparation and
      disposition, use without charge any trademark, trade name, copyright,
      patent or technical process used by Borrowers;

            (d) Publicly or privately sell or otherwise dispose of the
      Collateral as described in Section 5(e) below, without necessarily having
      the Collateral at the place of sale or disposition, and upon terms and in
      such manner as Secured Party may determine. Secured Party may be a
      purchaser of the Collateral at any public sale. Unless the Collateral is
      perishable or threatens to decline speedily in value or is of a type
      customarily sold on a recognized market, Secured Party will give Borrowers
      reasonable notice of the time and place of any public sale thereof or of
      the tune after which any private sale or any other intended disposition
      thereof is to be made, and such notice, if given to the Borrowers at least
      twenty (20) days prior to the date of any public sale or disposition or
      the date after which any private sale or disposition may occur, shall
      constitute reasonable notice of such sale or other disposition;

            (e) In accordance with the provisions of Section 5 below, notify any
      account of Borrowers or any other party obligated on or with respect to
      any of the Collateral to make payment to Secured Party or its nominee of
      any amounts due or to become due thereunder or with respect thereto and
      otherwise perform its obligations with respect to the Collateral on behalf
      of and for the benefit of Secured Party. Secured Party may enforce
      collection and performance with respect to any of the Collateral by suit
      or otherwise, in its own name or in the name of any of Borrowers or a
      nominee, and surrender, release or exchange all or any part thereof; and
      compromise, extend or renew (whether or not for longer than the original
      period) or transfer, assign or endorse for collection or otherwise, any
      indebtedness or obligation with respect to the Collateral, or evidenced
      thereby, and upon request of Secured Party, Borrowers will, at their own

                                       6
<PAGE>

      expense, notify any person obligated on or with respect to any of the
      Collateral to make payment and performance directly to, in the name of,
      and on behalf of Secured Party of any amounts or performance due or to
      become due thereunder or with respect thereto; and

            (f) Exercise any remedies of a Secured Party under the Uniform
      Commercial Code or any other applicable law.

            (g) Terminate any agreement or commitment of Secured Party for the
      granting of further credit to Borrowers.

      The proceeds of any sale under this Section 4 shall be applied first to
the payment of any sums owing to the Secured Party pursuant to the provisions of
the Notes and this Security Agreement, with any funds remaining after payment of
the foregoing to be paid to Borrowers.

      Secured Party shall have the right to enforce one or more remedies
hereunder, successively or concurrently, and such action shall not operate to
estop or prevent Secured Party from pursuing any further remedy which it may
have, and any repossession or retaking or sale of the Collateral pursuant to the
terms hereof shall not operate to release Borrowers until full payment of any
deficiency has been made in cash.

      5. GENERAL AUTHORITY. Each of Borrowers hereby irrevocably appoints
Secured Party its true and lawful attorney-in-fact (whether before or after an
Event of Default), with full power of substitution, in the name of Borrowers,
Secured Party or otherwise, for the sole use and benefit of Secured Party, but
at Borrowers' expense, to exercise, in Secured Party's sole and absolute
discretion, at any time all or any of the following powers:

            (a) to file the financing statements, financing statement amendments
      and continuation statements referred to in Section 2(e),

            (b) to file the Grant of Security Interest in Patents and Grant of
      Security Interest in Trademarks with the United States Patent and
      Trademark Office,

            (c) to demand, sue for, collect, receive and give acquittance for
      any and all monies due or to become due with respect to any Collateral or
      by virtue thereof,

            (d) to settle, compromise, compound, prosecute or defend any action
      or proceeding with respect to any Collateral,

            (e) to sell, transfer, assign or otherwise deal in or with the
      Collateral or the proceeds or avails thereof, as fully and effectually as
      if Secured Party were the absolute owner thereof, and

            (f) to extend the time of payment of any or all thereof and to make
      any allowance and other adjustments with reference to the Collateral,

                                       7
<PAGE>

provided, however, that the powers described in clauses (c), (d), (e) and (f)
above may be exercised by Secured Party only if an Event of Default then exists.
The power-of-attorney granted by Borrowers to Secured Party pursuant to this
Section 5 is coupled with an interest and shall be irrevocable during the terms
of this Security Agreement.

      6. PRESERVATION OF COLLATERAL BY SECURED PARTY. Should Borrowers fail or
refuse to make any payment, perform or observe any other covenant, condition or
obligation, or take any other action required by the terms of this Security
Agreement or the Notes at the time or in the manner provided, then Secured Party
may, at Secured Party's sole discretion, without notice to or demand upon
Borrowers, and without releasing Borrowers from any obligation, covenant or
condition hereof or under the Notes, make, perform, observe, or take any action
as Secured Party may deem necessary to protect its security interest in or
receive the value of the Collateral, including, but not limited to, the sale of
the Collateral. Furthermore, Secured Party may commence, defend, appeal or
otherwise participate in any action or proceeding purporting to affect its
security interest in or the value of the Collateral.

      7. NOTICES. All notices, requests, demands or other communication which
any party hereto may desire or may be required to give to any other party shall
be in writing, and shall be deemed given (i) if and when personally delivered,
or on the second business day after being deposited in United States mail
registered or certified, postage prepaid, or (ii) if and when sent by facsimile
transmission, and addressed to a party at its address set forth below, or to
such other address as such party may have designated to all other parties by
written notice in accordance herewith:

        If to Secured Party:         Virbac S.A.
                                     13 eme rue LID-BP 27
                                     06511 Carros cedex
                                     France
                                     Attention: Michel Garaudet, Chief Financial
                                     Officer
                                     Facsimile No.: 011 33 492 087 132

        with a copy to:              Virbac S.A.
                                     13 eme rue LID-BP 27
                                     06511 Carros cedex
                                     France
                                     Attention: Gerard Sicsic, General Counsel
                                     Facsimile No.: 011 33 492 087 132

        If to Borrowers:             Virbac Corporation
                                     3200 Meacham Boulevard
                                     Fort Worth, Texas 76137
                                     United States
                                     Attention: Chief Financial Officer or Chief
                                     Executive Officer
                                     (817) 831-8327

                                        8
<PAGE>

        with a copy to:              McGuireWoods LLP
                                     150 North Michigan Avenue
                                     Suite 2500
                                     Chicago, Illinois 60601
                                     Attention: David S. Guin, Esq.
                                     Facsimile No.: (312)920-7249

      8. WAIVER. By exercising or failing to exercise any of its rights, options
or elections hereunder or under the Notes, Secured Party shall not be deemed to
have waived any breach or default on the part of Borrowers or to have released
Borrowers from any of their obligations hereunder or under the Notes, unless
such waiver or release is in writing and signed by Secured Party. In addition,
the waiver by Secured Party of any breach hereof or default in payment of any
amounts due under the Notes shall not be deemed to constitute a waiver of any
succeeding breach or default.

      9. BINDING AGREEMENT. This Security Agreement and the Notes shall be
binding upon Borrowers, its successors and assigns and all other persons or
entities claiming under or through Borrowers, and the word "Borrowers," when
used herein, shall include all such persons or entities and any others liable
for the payment of the indebtedness secured hereby or any part thereof, whether
or not they have executed the Notes or this Security Agreement. The word
"Secured Party," when used herein, shall include Secured Party's successors and
assigns, including all other holders, from time to time, of the Notes.

      10. GOVERNING LAW; INTERPRETATION WAIVER OF JULY TRIAL. This Security
Agreement shall be governed by the laws of the State of Delaware. Wherever
possible, each provision of this Security Agreement shall be interpreted in such
a manner as to be effective and valid under applicable law, but if any provision
of this Security Agreement shall be prohibited by or invalid under such law,
such provision shall be ineffective to the extent of such prohibition or
invalidity, without invalidating the remainder of such provision or the
remaining provisions of this Security Agreement. Time is of the essence in this
Security Agreement. The Secured Party and each of the Borrowers waive trial by
jury in any dispute arising from, under or in connection with this Security
Agreement.

      11. MISCELLANEOUS.

            (a) Amendment. Neither this Security Agreement nor any provision
      hereof may be amended, modified, waived, discharged or terminated, nor may
      any of the Collateral be released, except by an instrument in writing duly
      signed by or on behalf of Secured Party hereunder.

            (b) Survival of Representations and Warranties. All representations,
      warranties and covenants of Borrowers made in this Security Agreement and
      the Notes shall survive until all of the obligations of Borrowers under
      the Notes shall have been fully paid and satisfied.

            (c) Headings. The Section headings are used herein for convenience
      of reference only and shall not define or limit the provisions of this
      Security Agreement.

                                       9
<PAGE>

      (d) Further Assurances. Each of Borrowers agrees that it will take all
such further actions, including, but not limited to, the filing of UCC financing
or continuation statements, or amendments thereto, and such other instruments or
notices, as may be reasonably necessary to perfect and preserve the security
interests granted or purported to be granted hereby. With respect to the
foregoing and the grant of the security interest hereunder, each of Borrowers
hereby authorizes Secured Party to file one or more financing or continuation
statements, and amendments thereto, relative to all or any part of the
Collateral without the signature of Borrowers where permitted by law. A carbon,
photographic or other reproduction of this Security Agreement or any financing
statement covering the Collateral or any part thereof shall be sufficient as a
financing statement where permitted by law. Each of Borrowers further agrees to
furnish to Secured Party, from time to time, at Secured Party's request,
statements and schedules further identifying and describing the Collateral and
such other books, records and reports in connection with the Collateral as
Secured Party may reasonably request, all in reasonable detail. Each of
Borrowers shall maintain books and records showing the Collateral in accordance
with sound accounting and management practices. Secured Party shall have the
right to examine each of Borrowers' books and records upon reasonable prior
notice and during normal business hours at any time.

      (e) Expenses. Borrowers will upon demand pay to Secured Party the amount
of any and all expenses, including the fees, expenses and disbursements of its
counsel, and of any experts or agents which Secured Party may incur in
connection with (i) the administration of this Security Agreement, (ii) the
custody, preservation, use or operation of, or the sale of, collection from or
other realization upon, any of the Collateral, (iii) the exercise or enforcement
of any of the rights of Secured Party hereunder, or (iv) the failure by
Borrowers to perform or observe any of the provisions hereof. Notwithstanding
the forgoing, all expenses of the Secured Party as provided above shall be
treated as advances of principal and shall accrue interest in accordance with
the provisions of Section 4(b) of the Notes.

      (f) Entire Agreement. This Security Agreement (together with the Notes)
contains the entire agreement between the parties hereto with respect to the
subject matter hereof and supersedes all prior agreements and understandings
between the parties with respect to the subject matter hereof (including,
without limitation, the Prior Agreement).

              [THE REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK]

                                       10
<PAGE>

      IN WITNESS WHEREOF, the parties hereto have caused this Amended and
Restated Security Agreement to be executed by their respective officers
thereunto duly authorized as of the day and year first above written.

                                                    BORROWERS:

                                                    VIRBAC CORPORATION
                                                    A DELAWARE CORPORATION

                                                    By: /s/ David G. Eller
                                                        ---------------------
                                                    Name: David G. Eller
                                                    Title: President

                                                    PM RESOURCES, INC.
                                                    A MISSOURI CORPORATION

                                                    By: /s/ David G. Eller
                                                        ---------------------
                                                    Name: David G. Eller
                                                    Title: President

                                                    ST. JON LABORATORIES, INC.
                                                    A CALIFORNIA CORPORATION

                                                    By: /s/ David G. Eller
                                                        ---------------------
                                                    Name: David G. Eller
                                                    Title: President

                                                    FRANCODEX LABORATORIES, INC.
                                                    A KANSAS CORPORATION

                                                    By: /s/ David G. Eller
                                                        ---------------------
                                                    Name: David G. Eller
                                                    Title: President

                                                    DELMARVA LABORATORIES, INC.
                                                    A VIRGINIA CORPORATION

                                                    By: /s/ David G. Eller
                                                        ---------------------
                                                    Name: David G. Eller
                                                    Title: President

                                       11
<PAGE>

                                                       VIRBAC AH,INC.
                                                       A DELAWARE CORPORATION

                                                       By: /s/ David G. Eller
                                                           ---------------------
                                                       Name: David G. Eller
                                                       Title: President

                                                       SECURED PARTY:

                                                       VIRBAC S. A.
                                                       A COMPANY ORGANIZED UNDER
                                                       THE LAWS OF THE REPUBLIC
                                                       OF FRANCE

                                                       By: _____________________
                                                       Name: ___________________
                                                       Title: __________________

                                       12
<PAGE>

                                                       VIRBAC AH, INC.
                                                       A DELAWARE CORPORATION

                                                       By: _____________________
                                                       Name: ___________________
                                                       Title:___________________

                                                       SECURED PARTY:

                                                       VIRBAC S. A.
                                                       A COMPANY ORGANIZED UNDER
                                                       THE LAWS OF THE REPUBLIC
                                                       OF FRANCE

                                                       By: /s/ Eric Maree
                                                           ---------------------
                                                       Name: Eric Maree
                                                       Title: President of the
                                                              Management Board

                                                  APPROUVE PAR SERVICE JURIDIQUE
                                                  APPROVED BY LEGAL DEPARTMENT

                                       12
<PAGE>

                                    EXHIBIT A

DEBTORS: Virbac Corporation, PM Resources, Inc., St. Jon Laboratories, Inc.,
         Francodex Laboratories, Inc., Delmarva Laboratories, Inc., Virbac AH,
         Inc.

SECURED PARTY: virbac S. A.

                            DESCRIPTION OF COLLATERAL

      The term "Collateral" shall mean, and the Collateral shall include all
assets and rights of the Borrowers, including, without limitation, all:

      (a)   inventory;

      (b)   accounts or notes receivable, accounts, including deposit accounts,
            drafts and other obligations and/or indebtedness owing to Borrowers;

      (c)   contract rights, books, records, chattel paper documents and
            instruments;

      (d)   motor vehicles, equipment, machinery;

      (e)   all patents, patent applications and other related rights including
            but not limited to, trust patents, patent applications and other
            rights;

      (f)   all trademarks, service marks, applications for trademarks, or
            service marks and other related rights including but not limited to,
            those trademarks, service marks, application for trademarks and
            service marks and other related rights;

      (g)   all product registration, product registration dossiers, permits,
            franchises, certificates, authorizations and approvals, application
            for the same and other related rights, including but not limited to,
            the product registration, permits, franchises, certificates,
            authorizations and approvals, applications for the same and other
            related rights;

                                       13
<PAGE>

      (h)   all of Borrowers' other intellectual proprietary rights and all
            other proprietary rights and confidential information, technology,
            processes, technical and scientific data, trade secrets, computer
            programs, source codes, customer lists, sales literature, catalogs,
            price lists, formulas and trial results and other similar rights or
            information;

in each case whether now owned or hereafter acquired by Borrowers and whether
now existing or hereafter created or arising and including all addition,
replacements, authorizations and accessories, all goodwill associated therewith
and any and all products, proceeds and revenues derived therefrom.

                                       14