**Exhibit99.1**

** **

**THIRD AMENDMENT TOOFFICE LEASE**

** **

THISTHIRD AMENDMENT TO OFFICE LEASE (“**Third Amendment**”) is made as of the28th day of February, 2008, between **RAFANELLIand NAHAS**, a California Limited Partnership, formally known asRAFANELLI and NAHAS, a California General Partnership (“**Owner**”), and **MWI Veterinary Supply**, an Idaho corporation (“**Tenant**”);

 

WITNESSETH

 

WHEREAS,the Owner and the Tenant did, under that date of June 20, 2003, enter intoa Lease (“**Original Lease**”)relating to and covering Suite 100 in the Building known as 651 StratfordDrive, Meridian, ID 83642 containing approximately 26,374 square feet of Net Rentable Area (“**Premises**”);

 

WHEREAS,the Owner and the Tenant entered into a First Amendment to Office Lease (“**First Amendment**”), relating to and coveringSuite 200 in the Building known as 651 Stratford Drive, Meridian, ID 83642containing approximately 4,453 square feet of Net Rentable Area (“**Premises**”);

 

WHEREAS,the Owner and the Tenant entered into a Second Amendment to Office Lease (“**Second Amendment**”) relating to and covering Suite 225in the Building known as 651 Stratford Drive, Meridian, ID 83642 containingapproximately 3,546 square feet of Net RentableArea (“**Premises**”);

 

WHEREAS,the Owner and the Tenant intend by this Third Amendment to amend the OriginalLease to incorporate Storage Space on the First Floor in the Building known as651 Stratford Drive, Meridian, ID 83642 containing approximately 237 squarefeet of Net RentableArea (“**Third Expansion Premises**”)as a part of the “Premises” covered thereby, to herein set forth the terms andconditions agreed for the leasing by the Tenant from the Owner of the ThirdExpansion Premises.

 

NOW,THEREFORE, IN CONSIDERATION OF the mutual promises and agreements of theparties as provided herein, and for other good and valuable consideration, theOwner and the Tenant do hereby agree as follows:

 

**1*.            *Recitals – Defined Terms**. The foregoing recitals are part of this Third Amendment, not mererecitals.  Unless expressly provided tothe contrary in this Third Amendment, the capitalized terms in this ThirdAmendment shall have the same meaning as said terms are defined in the OriginalLease.

 

**2*.            *Lease**. The parties acknowledge that the Original Lease, as amended by the Firstand Second Amendments, is in full force and effect and covers the Premisesdescribed therein.  Except as expresslyprovided in this Third Amendment, the terms, conditions and covenants of theOriginal Lease, as amended by the First and Second Amendments, shall remainunmodified and in full force and effect. As used hereafter “Lease” shall mean the Original Lease as amended bythe First and Second Amendments, and this ThirdAmendment.

 

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**3*.            *Third Expansion Premises- Term**.  The Third Expansion Premises shown onAmendment Exhibit C-1 includes 237 square feet of Rentable Area and ishereby leased by the Tenant from the Owner upon the terms and conditions setforth in the Original Lease, except as may be expressly provided to thecontrary in this Third Amendment.  Fromand after the Third Expansion Premises Commencement Date (as hereinafterdefined), the term “Premises” shall be deemed to include the Third ExpansionPremises, subject to the terms and conditions of this Third Amendment.  With respect to the leasing of the Third ExpansionPremises by the Tenant, the following terms and conditions shall apply:

 

**3.1**          **Term**.  The term of the Lease with respect to theThird Expansion Premises shall commence on March 1, 2008 (hereafter “**Third Expansion PremisesCommencement Date**”) and shall continue for the remainder of theInitial Term of the Lease, which Initial Term is agreed to expire January 31,2011.  The option to renew the Lease, asset forth in Exhibit H to the Original Lease, shall apply to all, but notless than all of the Premises, including the Third Expansion Premises.  TheBasic Annual Rent, as set forth in Exhibit H of the Original Lease, shallbe increased in accordance with the increased square footage leased by theTenant under the First, Second and Third Amendments.

 

**3.2          Rentable Area ofPremises**.  Effective on the Third Expansion PremisesCommencement Date, Paragraph 4 of the Basic Lease Provisions of theOriginal Lease is hereby amended to 34,610 square feet of Net Rentable Area of Premises for all purposes ofthe Lease.

 

**3.3          Annual Base Rent**. Commencing on the Third Expansion Premises Commencement Date until May 30,2008, total Annual Base Rent for the Premises and the Third Expansion Premisesshall be $264,408.00.  Thereafter, AnnualBase Rent will increase as outlined below. Accordingly, effective as of the Third Expansion Premises CommencementDate, the Annual Base Rent schedule set forth on Exhibit G to the OriginalLease and amended in the First Amendment shall be deemed to be replaced by thisSection 3.3. In addition to the Annual Base Rent for the Third ExpansionPremises, commencing on the Third Expansion Premises Commencement Date, theTenant shall pay to the Owner all other sums payable under the terms of theLease with respect to the Third Expansion Premises.

 
| **DATES**               | ** ** | **BASIC ANNUAL RENT** | ** ** | **MONTHLY INSTALLMENTS** | ** ** |
|-------------------------|------------|---------------------------------|------------|-------------------------------|------------|
| 6/1/08 – 11/30/09  |       | $                               | 272,340.00 |                          | $          | 22,695.00 |   |
| 12/1/09 – 11/30/10 |       | $                               | 280,510.00 |                          | $          | 23,376.00 |   |
| 12/1/10 – 1/31/11  |       | $                               | 0.00       |                          | $          | 0.00 |   |

 

**3.4          Improvements to Third Expansion Premises**. Tenant accepts the Third Expansion Premises in its “as-is” condition andOwner is under no obligation to complete any improvements to the ThirdExpansion Premises.

 

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**3.5          Premises Percentage**. Effective on the Third Expansion Premises Commencement Date, thePremises Percentage as set forth in Paragraph 5 of the Basic LeaseProvisions is hereby amended to be 78.119% for all purposes of the Lease.

 

**4*.            *Brokerage Commissions**. The Owner and Tenant agree that no real estate broker was involved inthis transaction and no fee or commission is due to any broker or agent inconnection with the execution of this Third Amendment.

 

**5*.            *RemainingTerms-Conflicts**.  Except as expressly provided in this ThirdAmendment, the terms and conditions of the Original Lease shall remainunchanged and in full force and effect. Any conflict between the terms and conditions of this Third Amendmentand the terms and conditions of the Original Lease shall be controlled by thisThird Amendment.

 

INWITNESS WHEREOF the undersigned have hereunto executed this Third Amendment asof the day and year first above written.

 
| **OWNER:**                                                             | ** **                             | **TENANT:**                                          |
|------------------------------------------------------------------------|----------------------------------------|------------------------------------------------------|
|                                                                   |                                   |                                                 |
|                                                                   |                                   |                                                 |
| **RAFANELLI & NAHAS,  L.P.,**a California Limited Partnership | ** **                             | **MWI VETERINARY SUPPLY CO.,**  an Idaho corporation |
|                                                                   |                                   |                                                 |   |   |
| By:                                                                    | Rafanelli & Nahas Management  |                                                 |   |   |
|                                                                   | Corporation, a California corporation, |                                                 |   |   |
|                                                                   | its General Partner                    |                                                 |   |   |
|                                                                   |                                   |                                                 | By: | /s/ James F. Cleary |
|                                                                   |                                   |                                                 |   | James F. Cleary |
|                                                                   | By:                                    | /s/ Ronald C. Nahas                                  |   | Dated: | November 21, 2008 |
|                                                                   | Ronald C. Nahas   Vice President       |                                                 |   |   |
|                                                                   | Dated:                                 | November 24, 2008                               |   |   |
|                                                                        |                                        |                                                      |  |  |  |  |  |  |  |  |  |

 

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