-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 OARHA2617tw0Q26qXKxriA/IZSg45BsWtyxBVbs4HHm+Yrhj//Oofk9BO9VTooIu
 Am3KqXmcVyeHmutK/WKjjg==

<SEC-DOCUMENT>0001193556-03-000019.txt : 20030530
<SEC-HEADER>0001193556-03-000019.hdr.sgml : 20030530
<ACCEPTANCE-DATETIME>20030530163019
ACCESSION NUMBER:		0001193556-03-000019
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20030530
FILED AS OF DATE:		20030530

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			AYLESWORTH WILLIAM A
		CENTRAL INDEX KEY:			0001190231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	333-72155
		FILM NUMBER:		03726314

	BUSINESS ADDRESS:	
		STREET 1:		TEXAS INSTRUMENTS
		STREET 2:		12500 T1 BLVD.
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75243

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			HESKA CORP
		CENTRAL INDEX KEY:			0001038133
		STANDARD INDUSTRIAL CLASSIFICATION:	BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
		IRS NUMBER:				770192527
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1613 PROSPECT PARKWAY
		CITY:			FORT COLLINS
		STATE:			CO
		ZIP:			80525
		BUSINESS PHONE:		9704937272

	MAIL ADDRESS:	
		STREET 1:		1613 PROSPECT PARKWAY
		CITY:			FORT COLLINS
		STATE:			CO
		ZIP:			80525
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgardoc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0101</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2003-05-30</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001038133</issuerCik>
        <issuerName>HESKA CORP</issuerName>
        <issuerTradingSymbol>HSKA</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001190231</rptOwnerCik>
            <rptOwnerName>AYLESWORTH WILLIAM A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>  </rptOwnerStreet1>
            <rptOwnerStreet2>  </rptOwnerStreet2>
            <rptOwnerCity>  </rptOwnerCity>
            <rptOwnerState>  </rptOwnerState>
            <rptOwnerZipCode>  </rptOwnerZipCode>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeSecurity>
        <securityTitle>
            <value>Non-Qualified Stock Option (right to buy)</value>
        </securityTitle>
        <conversionOrExercisePrice>
            <value>1.5</value>
        </conversionOrExercisePrice>
        <transactionDate>
            <value>2003-05-29</value>
        </transactionDate>
        <transactionCoding>
            <transactionFormType>4</transactionFormType>
            <transactionCode>A</transactionCode>
            <equitySwapInvolved>0</equitySwapInvolved>
        </transactionCoding>
        <transactionAmounts>
            <transactionShares>
                <value>42000</value>
            </transactionShares>
            <transactionValue>
                <value>0</value>
            </transactionValue>
            <transactionAcquiredDisposedCode>
                <value>A</value>
            </transactionAcquiredDisposedCode>
        </transactionAmounts>
        <exerciseDate>
            <value>2004-05-29</value>
                <footnoteId id="F1"/>
        </exerciseDate>
        <expirationDate>
            <value>2013-05-29</value>
        </expirationDate>
        <underlyingSecurity>
            <underlyingSecurityTitle>
                <value>Common Stock</value>
            </underlyingSecurityTitle>
            <underlyingSecurityShares>
                <value>42000</value>
            </underlyingSecurityShares>
        </underlyingSecurity>
        <postTransactionAmounts>
            <valueOwnedFollowingTransaction>
                <value>42000</value>
            </valueOwnedFollowingTransaction>
        </postTransactionAmounts>
        <ownershipNature>
            <directOrIndirectOwnership>
                <value>D</value>
            </directOrIndirectOwnership>
        </ownershipNature>
    </derivativeSecurity>

    <footnotes>
        <footnote id="F1">This option is exercisable on the date of grant, but the underlying shares are subject to repurchase by the Company until the option vests in full on May 29, 2004. </footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>By: Michael A Bent  For: William A Aylesworth</signatureName>
        <signatureDate>2003-05-30</signatureDate>
    </ownerSignature>

</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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