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                                                                   EXHIBIT 10.27


                                 April 15, 2005


Virbac Corporation and Subsidiaries
3200 Meacham Boulevard
Fort Worth, Texas 76137
Attention:    Jean M. Nelson, Executive Vice
              President and Chief Financial Officer

                  Re:  Waiver of 2001 and 2002 Financial Covenant Defaults and
                       Amendments to Forbearance Agreement

Dear Ms. Nelson:

         Reference is made to that certain Credit Agreement dated as of
September 7, 1999 made by and among Virbac Corporation, PM Resources, Inc., St.
Jon Laboratories, Inc., Francodex Laboratories, Inc., Virbac AH, Inc. and
Delmarva Laboratories, Inc. (collectively, the "Borrowers"), and First Bank
("Bank"), as the same has been from time to time amended (as amended, the
"Credit Agreement;" capitalized terms used herein and not otherwise defined
shall have the meanings given to such terms in the Credit Agreement). You have
informed the undersigned Bank of the Borrowers' noncompliance with the financial
covenants set forth in Section 7.1(i)(i) (ratio of Consolidated EBITDA to
Consolidated Debt Service) of the Credit Agreement for the fiscal quarters
ending March 31, 2001 through and including December 31, 2001, and in Section
7.1(i)(ii) (Consolidated Net Worth) of the Credit Agreement for the fiscal
quarters ending March 31, 2001 through and including December 31, 2002, which
covenant defaults constitute Events of Default under Section 8.3 of the Credit
Agreement, and you have requested waivers of the same.

         By this letter, the undersigned Bank hereby waives the Borrowers'
noncompliance under Section 7.1(i)(i) of the Credit Agreement for the fiscal
quarters ending March 31, 2001 through and including December 31, 2001 and
Borrowers' noncompliance under Section 7.1(i)(ii) of the Credit Agreement for
the fiscal quarters ending March 31, 2001 through and including December 31,
2002, and the undersigned Bank further waives any Default or Event of Default
under the Credit Agreement caused by such noncompliance for such fiscal
quarters. These waivers shall constitute waivers only of the above-referenced
covenants and only with respect to the specified fiscal quarters. Such waivers
shall not be deemed to be a waiver for any other occurrence under the
above-referenced Sections 7.1(i)(i) and 7.1(i)(ii) of the Credit Agreement or
for any other provisions contained in the Credit Agreement or any of the other
Transaction Documents. Such waivers shall also not be deemed to create any
custom, practice or course of dealing between Borrowers and the Bank, and
Borrowers should not rely on such present waivers to anticipate or expect any
other or similar waivers in the future.

         You have also requested certain amendments to the Forbearance Agreement
dated as of April 9, 2004 made by and among Borrowers and Bank, as the same has
been from time to time amended (the "Forbearance Agreement") to: (i) permit the
delivery of the audited financial statements for Borrowers' fiscal years ending
December 31, 2003, December 31, 2002, December 31, 2001 and December 31, 2000 on
or before May 2, 2005 instead of on or before April 18, 2005 as set forth in
Section 1(b)(iii)(C) of the Forbearance Agreement, (ii) delete the requirement
for an unqualified opinion of Borrowers' accountants with respect to such
financial statements, and (iii) delete the requirement of Section 1(b)(iii)(E)
of the



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Forbearance Agreement for delivery by April 15, 2005 of detailed projections for
Borrowers fiscal year ending December 31, 2005.

         Subject to the conditions of this letter, Borrowers and Bank hereby
agree that Section 1(b)(iii)(C) of the Forbearance Agreement shall be amended to
read in its entirety as follows:

                  (C) on or before May 2, 2005, the consolidated balance sheet
         of Borrowers and their Consolidated Subsidiaries as of December 31,
         2003 and the related consolidated statements of income, retained
         earnings and cash flows for the fiscal year ended as of December 31,
         2003, all with consolidating disclosures and setting forth in each
         case, in comparative form, the figures for the previous fiscal year,
         together with any and all restated financial statements (balance sheets
         and statements of income, retained earnings and cash flows) for the
         fiscal years (or any periods during the fiscal years) ending December
         31, 2002, December 31, 2001 and December 31, 2000, all such financial
         statements to be prepared in accordance with Generally Accepted
         Accounting Principles consistently applied and audited by
         PriceWaterhouse Coopers;

         Subject to the conditions of this letter, Borrowers and Bank hereby
further agree that Section 1(b)(iii)(E) of the Forbearance Agreement shall be
deleted in its entirety and shall be left blank intentionally.

         Capitalized terms used in this letter and not otherwise defined shall
have their meanings under the Forbearance Agreement.

         Please indicate your acceptance and acknowledgment of the
above-referenced waivers on the above stated conditions and your acknowledgment
and agreement to the amendments contained herein by signing and returning the
enclosed duplicate original of this letter in the space provided below. The
amendments set forth herein shall not be effective unless counterpart originals
of this letter, signed by a duly authorized officer of each of the Borrowers and
by a duly authorized officer of Bank One, NA, are returned to Bank on or before
April 20, 2005.

         This notice is provided pursuant to Section 432.047, R.S.Mo. As used
herein, "creditor" means each of the Bank and its participant, Bank One, NA, the
"credit agreement" means the Loan Agreement, as amended by the Forbearance
Agreement, and as each such document has been further amended from time to time,
and "this writing" means the Loan Agreement, as amended by the Forbearance
Agreement, and as each such document has been further amended from time to time,
the Note, the other Transaction Documents, all guaranties executed by any other
Obligors, and any other agreement executed in connection herewith or therewith.
ORAL AGREEMENTS OR COMMITMENTS TO LOAN MONEY, EXTEND CREDIT OR TO FORBEAR FROM
ENFORCING REPAYMENT OF A DEBT INCLUDING PROMISES TO EXTEND OR RENEW SUCH DEBT
ARE NOT ENFORCEABLE, REGARDLESS OF THE LEGAL THEORY UPON WHICH IT IS BASED THAT
IS IN ANY WAY RELATED TO THE CREDIT AGREEMENT. TO PROTECT YOU (BORROWER(S)) AND
US (CREDITOR) FROM MISUNDERSTANDING OR DISAPPOINTMENT, ANY AGREEMENTS WE REACH
COVERING SUCH MATTERS ARE CONTAINED IN THIS WRITING, WHICH IS THE COMPLETE AND
EXCLUSIVE STATEMENT OF THE AGREEMENT BETWEEN US, EXCEPT AS WE MAY LATER AGREE IN
WRITING TO MODIFY IT. This Agreement embodies the entire agreement and
understanding between the Borrowers and the Bank and supersedes all prior
agreements and understandings (oral or written) relating to the subject matter
hereof.



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                                         Very truly yours,

                                         FIRST BANK


                                         By: /s/ Traci Dodson
                                            ------------------------------------
                                            Traci Dodson, Vice President


ACKNOWLEDGED AND AGREED THIS
15th DAY OF APRIL, 2005

VIRBAC CORPORATION
PM RESOURCES, INC.
ST. JON LABORATORIES, INC.
VIRBAC AH, INC.
FRANCODEX LABORATORIES, INC.
DELMARVA LABORATORIES, INC.


By: /s/ Jean M. Nelson
   ----------------------------------------------
   Jean M. Nelson, Executive Vice President
   and Chief Financial Officer

CONSENTED AND AGREED TO THIS 19th
DAY OF APRIL, 2005

JPMORGAN CHASE BANK, N.A. formerly known
as and successor by merger with Bank One, N.A.


By: /s/ Jennifer Baggs
   ----------------------------------------------
Title: Vice President
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