Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  Zachara Claudine
2. Date of Event Requiring Statement (Month/Day/Year)
05/02/2011
3. Issuer Name and Ticker or Trading Symbol
HESKA CORP [HSKA]
(Last)
(First)
(Middle)
3760 ROCKY MOUNTAIN AVENUE
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
VP, Marketing
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

LOVELAND, CO 80538
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock 20
D
 

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Incentive Stock Option (right to buy) (1) 11/04/2008 11/03/2018 Common Stock 900 $ 4.4 D  
Incentive Stock Option (right to buy) (2) 11/10/2009 11/09/2019 Common Stock 2,000 $ 4.5 D  
Incentive Stock Option (right to buy) (3) 12/31/2010 12/30/2020 Common Stock 4,500 $ 4.96 D  
Incentive Stock Option (right to buy) (4) 09/14/2009 09/13/2019 Common Stock 2,500 $ 5 D  
Incentive Stock Option (right to buy) (5) 03/30/2005 03/30/2015 Common Stock 708 $ 8.8 D  
Incentive Stock Option (right to buy) (6) 04/10/2003 04/10/2013 Common Stock 600 $ 9.5 D  
Incentive Stock Option (right to buy) (7) 02/05/2002 02/05/2012 Common Stock 1,050 $ 10.6 D  
Incentive Stock Option (right to buy) (8) 05/18/2004 05/18/2014 Common Stock 750 $ 15.9 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Zachara Claudine
3760 ROCKY MOUNTAIN AVENUE
LOVELAND, CO 80538
      VP, Marketing  

Signatures

By: Jason A. Napolitano For: Claudine Zachara 05/04/2011
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) This option vests and becomes exercisable in monthly equal installments over four (4) years through November 4, 2012.
(2) This option vests and becomes exercisable in monthly equal installments over four (4) years through November 10, 2013.
(3) This option vests and becomes exercisable in monthly equal installments over four (4) years through December 31, 2014.
(4) This option vests and becomes exercisable in monthly equal installments over four (4) years through September 14, 2013.
(5) This option vested immediately. Excludes the option purchase 0.5 fractional shares resulting from a December 2010 1-for-10 reverse stock split.
(6) This option vested monthly in equal installments over four (4) years through April 10, 2007. Vesting was accelerated to full vest on March 30, 2005. Excludes the option to purchase 0.5 fractional shares resulting from a December 2010 1-for-10 reverse stock split.
(7) This option vested monthly in equal installments over four (4) years through February 5, 2006. Vesting was accelerated to full vest on March 30, 2005. Excludes the option to purchase 0.9 fractional shares resulting from a December 2010 1-for-10 reverse stock split.
(8) This option vested monthly in equal installments over four (4) years through May 18, 2008. Vesting was accelerated to full vest on December 2, 2004.

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