Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN 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 *
GRIEVE ROBERT B
   2. Issuer Name and Ticker or Trading Symbol
HESKA CORP [HSKA] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Chief Executive Officer
(Last)
(First)
(Middle)
3760 ROCKY MOUNTAIN AVENUE		 3. Date of Earliest Transaction (Month/Day/Year)
03/26/2012
(Street)

LOVELAND, CO 80538		 4. If Amendment, Date Original Filed(Month/Day/Year)
 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 Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)		 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)		 4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)		 5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)		 6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)		 7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 03/26/2012   M   6,999 A $ 3.4 60,057 D  
Common Stock 03/26/2012   M   1,876 A $ 4.4 61,933 D  
Common Stock 03/26/2012   M   23,123 A $ 4.4 85,056 D  
Common Stock 03/26/2012   M   1,625 A $ 4.5 86,681 D  
Common Stock 03/26/2012   M   7,218 A $ 4.96 93,899 D  
Common Stock 03/26/2012   M   13,541 A $ 4.5 107,440 D  
Common Stock 03/26/2012   M   1 A $ 7.72 107,441 D  
Common Stock 03/26/2012   M   1 A $ 8.08 107,442 D  
Common Stock 03/26/2012   M   1 (1) A $ 5.06 (2) 107,443 (1) D  
Common Stock 03/26/2012   F   30,141 (3) D $ 11.78 77,299 (1) D  
Common Stock               3,077 I by Daughter I (4)
Common Stock               3,077 I by Daughter II (5)
Common Stock               1,564 I by Spouse (6)

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)		 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)		 5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)		 6. Date Exercisable and Expiration Date
(Month/Day/Year)		 7. Title and Amount of Underlying Securities
(Instr. 3 and 4)		 8. Price of Derivative Security
(Instr. 5)		 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)		 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Non-Qualified Stock Option (right to buy) $ 3.4 03/26/2012   M     6,999 01/06/2003 01/06/2013 Common Stock 6,999 $ 0 0 D  
Incentive Stock Option (right to buy) $ 4.4 03/26/2012   M     1,876 11/04/2008 11/03/2018 Common Stock 1,876 $ 0 0 D  
Non-Qualified Stock Option (right to buy) $ 4.4 03/26/2012   M     23,123 11/04/2008 11/03/2018 Common Stock 23,123 $ 0 0 D  
Incentive Stock Option (right to buy) $ 4.5 03/26/2012   M     1,625 11/10/2009 11/09/2019 Common Stock 1,625 $ 0 0 D  
Non-Qualified Stock Option (right to buy) $ 4.96 03/26/2012   M     7,218 12/31/2010 12/30/2020 Common Stock 7,218 $ 0 0 D  
Non-Qualified Stock Option (right to buy) $ 4.5 03/26/2012   M     13,541 11/10/2009 11/09/2019 Common Stock 13,541 $ 0 0 D  
Non-Qualified Stock Option (right to buy) $ 7.72 03/26/2012   M     1 03/30/2009(7) 01/31/2013(7) Common Stock 1 $ 0 0 D  
Non-Qualified Stock Option (right to buy) $ 8.08 03/26/2012   M     1 03/30/2009(8) 01/31/2013(8) Common Stock 1 $ 0 0 D  
Non-Qualified Stock Option (right to buy) $ 5.06 03/26/2012   M     1 01/31/2007(2) 04/30/2012(2) Common Stock 1 (2) $ 0 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
GRIEVE ROBERT B
3760 ROCKY MOUNTAIN AVENUE
LOVELAND, CO 80538		   X     Chief Executive Officer  

Signatures

 By: Jason A. Napolitano For: Robert B. Grieve   03/26/2012
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(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) Includes one share jointly owned with Jason Napolitano.
(2) Represents a combination of stock option exercises involving fractional shares: 0.6 shares at a price of $3.40 per share from a stock option granted to Dr. Grieve on 01/6/2003 exercisable on 01/06/04 with expiration date 01/06/13, 0.2 shares at a price of $8.10 per share from a stock option granted to Jason Napolitano on 04/30/02 exercisable on 04/30/02 with expiration date 04/30/12, 0.1 shares at a price of $7.00 per share from a stock option granted on 5/31/02 exercisable on 5/31/06 with expiration date 5/31/12 and 0.1 shares at a price of $7.00 per share from a stock option granted on 1/31/03 exercisable on 1/31/07 with expiration date 1/31/13. Dr. Grieve offered to deliver shares valued at $2.04 and Jason Napolitano offered to deliver $3.02 in cash for these stock option exercises.
(3) Dr. Grieve offered to deliver 30,141 previously owned shares to fulfill all exercise price and minimum statutory tax withholding obligations for his stock option exercises referenced herein.
(4) Gifts under the Uniform Gifts to Minors Act to minor daughter (Megan Grieve) who shares reporting person's household. The reporting person is the custodian of such shares but disclaims beneficial ownership of these shares.
(5) Gifts under the Uniform Gifts to Minors Act to minor daughter (Madeline Grieve) who shares reporting person's household. The reporting person is the custodian of such shares but disclaims beneficial ownership of these shares.
(6) Dr. Grieve disclaims beneficial ownership of all securities of the Issuer owned by his wife.
(7) Represents a combination of stock option exercises involving fractional shares: 0.6 shares at a price of $7.00 per share from a stock option granted on 01/31/2003 with expiration date 01/31/2013 and 0.4 shares at a price of $8.80 from a stock option granted on 3/30/2005 with expiration date 03/30/2015.
(8) Represents a combination of stock option exercises involving fractional shares: 0.5 at a price of $8.80 per share from a stock option granted on 03/30/2005 with expiration date 03/30/2015, 0.4 shares at a price of $7.00 from a stock option granted on1/31/2003 with expiration date 01/31/2013 and 0.1 share at a price of $8.80 from a stock option granted on 3/30/2005 with expiration date 03/30/2015.

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