X0303 4 2011-02-14 0 0001323974 MWI Veterinary Supply, Inc. MWIV 0001334044 Rebholtz Robert N JR 651 S. STRATFORD DR., SUITE 100 MERIDIAN ID 83642 1 0 0 0 Common Stock, par value $0.01 per share 7000 D Common Stock, par value $0.01 per share 2011-02-14 4 S 0 3026 69.9432 D 407995 I By Agri Beef Co. Common Stock, par value $0.01 per share 2011-02-14 4 S 0 2799 70.4806 D 405196 I By Agri Beef Co. Common Stock, par value $0.01 per share 2011-02-15 4 S 0 5096 70.5597 D 400100 I By Agri Beef Co. Common Stock, par value $0.01 per share 2011-02-15 4 S 0 100 70.94 D 400000 I By Agri Beef Co. The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by Agri Beef Co. on November 30, 2010. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $69.34 to $70.25, inclusive. Mr. Rebholtz has provided to MWI Veterinary Supply, Inc. (the "Company") and undertakes to provide to any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote. Mr. Rebholtz is a principal stockholder, director, President and Chief Executive Officer of Agri Beef Co. Mr. Rebholtz expressly disclaims beneficial ownership of any shares held by Agri Beef Co. that exceed his pecuniary interest therein. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $70.35 to $70.77, inclusive. Mr. Rebholtz has provided to MWI Veterinary Supply, Inc. (the "Company") and undertakes to provide to any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $69.86 to $70.85, inclusive. Mr. Rebholtz has provided to MWI Veterinary Supply, Inc. (the "Company") and undertakes to provide to any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote. Ryan Cleverley as attorney-in-fact for Robert N. Rebholtz, Jr. 2011-02-16