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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549


                                  SCHEDULE 13G


                    UNDER THE SECURITIES EXCHANGE ACT OF 1934
                                (AMENDMENT NO. )*

                                HESKA CORPORATION
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                                (NAME OF ISSUER)


                    COMMON STOCK, $0.001 PAR VALUE PER SHARE
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                         (TITLE OF CLASS OF SECURITIES)


                                    42805E108
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                                 (CUSIP NUMBER)


                                DECEMBER 31, 2007
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             (DATE OF EVENT WHICH REQUIRES FILING OF THIS STATEMENT)


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CHECK THE APPROPRIATE BOX TO DESIGNATE THE RULE PURSUANT TO WHICH THIS SCHEDULE
IS FILED:

[X]     RULE 13d-1(b)

[_]     RULE 13d-1(c)

[_]     RULE 13d-1(d)

*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).

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CUSIP NO. 42805E108                     13G                    PAGE 2 OF 5 PAGES
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  1   NAME OF REPORTING PERSON:
      I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY):


      Ashford Capital Management, Inc.
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  2   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
                                                                         (a) [ ]
                                                                         (b) [ ]
----- --------------------------------------------------------------------------
  3   SEC USE ONLY

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  4   CITIZENSHIP OR PLACE OF ORGANIZATION

      Delaware
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                            5   SOLE VOTING POWER

                                3,197,500 shares
       NUMBER OF          ----- ------------------------------------------------
         SHARES             6   SHARED VOTING POWER
      BENEFICIALLY
        OWNED BY                0 shares
          EACH            ----- ------------------------------------------------
       REPORTING            7   SOLE DISPOSITIVE POWER
         PERSON
          WITH                  3,197,500 shares
                          ----- ------------------------------------------------
                            8   SHARED DISPOSITIVE POWER

                                0 shares
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  9   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

      3,197,500 shares

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 10   CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* [_]


----- --------------------------------------------------------------------------
 11   PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

      6.23%
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 12   TYPE OF REPORTING PERSON*

      IA
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CUSIP NO. 42805E108                     13G                    PAGE 3 OF 5 PAGES
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ITEM 1.

         (a) Name of Issuer:

             Heska Corporation

         (b) Address of Issuer's Principal Executive Offices:

             3760 Rocky Mountain Avenue, Loveland, Colorado 80538

ITEM 2.

         (a) Name of Person Filing:

             Ashford Capital Management, Inc.

         (b) Address of Principal Business Office or, if none, Residence:

             P.O. Box 4172, Wilmington, DE 19807

         (c) Citizenship: A Delaware Corporation

         (d) Title of Class of Securities: Common Stock, $0.001 Par Value Per
             Share

         (e) CUSIP Number: 42805E108

ITEM 3.      IF THIS STATEMENT IS FILED PURSUANT TO SS.SS.240.13D-1(B) OR
             240.13D-2(B) OR (C), CHECK WHETHER THE PERSON FILING IS A:

         (a) |_| Broker or dealer registered under section 15 of the Act
         (b) |_| Bank as defined in section 3(a)(6) of the Act
         (c) |_| Insurance company as defined in section 3(a)(19) of the Act
         (d) |_| Investment company registered under section 8 of the Investment
                 Company Act of 1940
         (e) |X| An investment adviser in accordance with ss.240.13d-1(b)(1(ii)
                 (E)
         (f) |_| An employee benefit plan or endowment fund in accordance with
                 ss.240.13d-1(b)(1)(ii)(F)
         (g) |_| A parent holding company or control person in accordance with
                 ss.240.13d-1(b)(1)(ii)(G)
         (h) |_| A savings association as defined in section 3(b) of the Federal
                 Deposit Insurance Act
         (i) |_| A church plan that is excluded from the definition of an
                 investment company under section 3(c)(14) of the Investment
                 Company Act of 1940
         (j) |_| Group, in accordance with ss.240.13d-1(b)-1(ii)(J)

ITEM 4.  OWNERSHIP

       Provide the following information regarding the aggregate number and
percentage of the class of securities of the issuer identified in Item 1.

             (a) Amount Beneficially Owned: 3,197,500 shares

             (b) Percent of Class: 6.23%

                 The foregoing percentage is calculated based on 51,355,349
                 shares of Common Stock reported to be outstanding as of
                 November 12, 2007 in the Issuer's Quarterly Report filed on
                 Form 10-Q.

             (c) Number of shares as to which such person has:

                 (i) Sole power to vote or to direct the vote: 3,197,500 shares

                 (ii) Shared power to vote or to direct the vote: 0 shares


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CUSIP NO. 42805E108                     13G                    PAGE 4 OF 5 PAGES
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                 (iii) Sole power to dispose or to direct the disposition of:
                       3,197,500 shares

                 (iv) Shared power to dispose or to direct the disposition of:
                      0 shares

ITEM 5.  OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS

         If this statement is being filed to report the fact that as of the date
hereof the reporting person has ceased to be the beneficial owner of more than
five percent of the class of securities, check the following |_|. N/A

ITEM 6.  OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON

         The shares reported by the Reporting Person, a registered investment
advisor, are held in separate individual client accounts, one separate limited
partnership and nine commingled funds. No single client account owns more than
5% of the class of securities of the issuer identified in Item 1.

ITEM 7.  IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE
         SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY

         N/A

ITEM 8.  IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP

         N/A

ITEM 9.  NOTICE OF DISSOLUTION OF GROUP

         N/A

ITEM 10. CERTIFICATION

         By signing below I certify that, to the best of my knowledge and
belief, the securities referred to above were acquired and are held in the
ordinary course of business and were not acquired and are not held for the
purpose of or with the effect of changing or influencing the control of the
issuer of the securities and were not acquired and are not held in connection
with or as a participant in any transaction having that purpose or effect.


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CUSIP NO. 42805E108                     13G                    PAGE 5 OF 5 PAGES
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                                    SIGNATURE

         After reasonable inquiry and to the best of its knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.

Date:    February 14, 2008

ASHFORD CAPITAL MANAGEMENT, INC.


By:      /s/ Anthony M. Petrucci
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         Anthony M. Petrucci
         Chief Financial Officer and Chief Compliance Officer