As filed with the Securities and Exchange Commission on January 7, 2002
                                                    Registration No. 333-_______
================================================================================
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                ----------------

                                    FORM S-3
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                                ----------------

                                HESKA CORPORATION
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

                                ----------------

           DELAWARE                                           77-0192527
 (STATE OR OTHER JURISDICTION OF                           (I.R.S. EMPLOYER
  INCORPORATION OR ORGANIZATION)                        IDENTIFICATION NUMBER)

                              1613 PROSPECT PARKWAY
                          FORT COLLINS, COLORADO 80525
                                 (970) 493-7272
    (ADDRESS, INCLUDING ZIP CODE, AND TELEPHONE NUMBER, INCLUDING AREA CODE,
                  OF REGISTRANT'S PRINCIPAL EXECUTIVE OFFICES)

                                ----------------

                             ROBERT B. GRIEVE, PH.D
                           CHIEF EXECUTIVE OFFICER AND
                              CHAIRMAN OF THE BOARD
                                HESKA CORPORATION
                              1613 PROSPECT PARKWAY
                          FORT COLLINS, COLORADO 80525
                                 (970) 493-7272
 (NAME, ADDRESS, INCLUDING ZIP CODE, AND TELEPHONE NUMBER, INCLUDING AREA CODE,
                              OF AGENT FOR SERVICE)

                                ----------------

                                   Copies to:
                             KAREN A. DEMPSEY, ESQ.
                            WILSON SONSINI GOODRICH &
                                     ROSATI
                            PROFESSIONAL CORPORATION
                                   ONE MARKET
                         SPEAR STREET TOWER, SUITE 3300
                            SAN FRANCISCO, CALIFORNIA
                                      94105
                                 (415) 947-2000
                               FAX: (415) 947-2099

                                ----------------

      APPROXIMATE DATE OF COMMENCEMENT OF PROPOSED SALE TO THE PUBLIC: From time
to time after the effective date of this Registration Statement.

      If the only securities being registered on this Form are being offered
pursuant to dividend or interest reinvestment plans, please check the following
box. [ ]

      If any of the securities being registered on this Form are to be
offered on a delayed or continuous basis pursuant to Rule 415 under the
Securities Act of 1933, other than securities offered only in connection with
dividend or interest reinvestment plans, check the following box. [X]

      If this Form is filed to register additional securities for an offering
pursuant to Rule 462(b) under the Securities Act, please check the following box
and list the Securities Act registration statement number of the earlier
effective registration statement for the same offering. [ ]

      If this Form is a post-effective amendment filed pursuant to Rule 462(c)
under the Securities Act, check the following box and list the Securities Act
registration statement number of the earlier effective registration statement
for the same offering. [ ]

      If delivery of the prospectus is expected to be made pursuant to Rule 434,
please check the following box. [ ]

                                ----------------

                         CALCULATION OF REGISTRATION FEE



                                                  PROPOSED   PROPOSED
                                                  MAXIMUM     MAXIMUM
                                                  OFFERING   AGGREGATE     AMOUNT OF
   TITLE OF EACH CLASS OF       AMOUNT TO BE     PRICE PER   OFFERING    REGISTRATION
SECURITIES TO BE REGISTERED      REGISTERED       SHARE(1)    PRICE(1)        FEE
---------------------------      ----------       --------    --------   ------------
                                                             
Common Stock, $0.001 par
 value per share              7,792,768 shares     $1.31      $10,208,526 $  2,440


      (1) The price of $1.31 per share, which was the average of the high and
low prices of the Registrant's common stock on the Nasdaq National Market on
January 4, 2002 is set forth solely for the purposes of calculating the
registration fee in accordance with Rule 457(c) of the Securities Act.

                                ----------------

      THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE OR
DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT SHALL
FILE A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS REGISTRATION
STATEMENT SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION 8(a) OF
THE SECURITIES ACT OR UNTIL THE REGISTRATION STATEMENT SHALL BECOME EFFECTIVE ON
SUCH DATE AS THE SECURITIES AND EXCHANGE COMMISSION, ACTING PURSUANT TO SECTION
8(a), MAY DETERMINE.
================================================================================



THE INFORMATION IN THIS PROSPECTUS IS NOT COMPLETE AND MAY BE CHANGED. THESE
SECURITIES MAY NOT BE SOLD UNTIL THE REGISTRATION STATEMENT FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION IS EFFECTIVE. THIS PROSPECTUS IS NOT AN OFFER
TO SELL THESE SECURITIES AND IT IS NOT SOLICITING AN OFFER TO BUY THESE
SECURITIES IN ANY STATE WHERE THE OFFER OR SALE IS NOT PERMITTED.



PROSPECTUS

(Subject to Completion, dated January 7, 2002)

                                7,792,768 Shares

                                  [HESKA LOGO]


                                HESKA CORPORATION

                                  Common Stock

                                ----------------

      This prospectus relates to the public offering, which is not being
underwritten, of up to 7,792,768 shares of our Common Stock which is held by
certain investors. We issued these shares of our Common Stock to the selling
stockholders identified in this prospectus in a private placement.

      The prices at which such stockholders may sell the shares will be
determined by the prevailing market price for the shares or in negotiated
transactions. We will not receive any of the proceeds from the sale of the
shares.

      Our Common Stock is listed on the Nasdaq National Market under the symbol
"HSKA." On January 4, 2002, the closing price for our Common Stock was $1.35
per share.

                                ----------------

      INVESTING IN OUR COMMON STOCK INVOLVES CERTAIN RISKS. SEE "RISK FACTORS"
BEGINNING ON PAGE 3.

                                ----------------

      NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES
COMMISSION HAS APPROVED OR DISAPPROVED OF THESE SECURITIES OR PASSED UPON THE
ADEQUACY OR ACCURACY OF THIS PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A
CRIMINAL OFFENSE.

                                ----------------

                  THE DATE OF THIS PROSPECTUS IS    , 2002.





                                TABLE OF CONTENTS



                                                                            PAGE
                                                                            ----
                                                                         
Heska Corporation........................................................     1

Forward-Looking Statements...............................................     1

Risk Factors.............................................................     2

Use of Proceeds..........................................................     9

Selling Stockholders.....................................................    10

Plan Of Distribution.....................................................    12

Legal Matters............................................................    14

Experts..................................................................    14

Where You Can Find More Information......................................    14


     No person has been authorized to give any information or to make any
representations other than those contained in this prospectus in connection
with the offering made hereby, and if given or made, such information or
representations must not be relied upon as having been authorized by Heska
Corporation (referred to in this prospectus as "Heska", the "Company", the
"Registrant", "we" and "our"), any selling stockholder or by any other person.
Neither the delivery of this prospectus nor any sale made hereunder shall,
under any circumstances, create any implication that information herein is
correct as of any time subsequent to the date hereof.  This prospectus does not
constitute an offer to sell or a solicitation of an offer to buy any security
other than the securities covered by this prospectus, nor does it constitute
an offer to or solicitation of any person in any jurisdiction in which such
offer or solicitation may not lawfully be made.





                                HESKA CORPORATION

      We discover, develop, manufacture and market companion animal health
products. We have a sophisticated scientific effort devoted to applying
biotechnology to create a broad range of pharmaceutical, vaccine and diagnostic
products for the companion animal health market. In addition to our
pharmaceutical, vaccine and diagnostic products, we also sell veterinary
diagnostic and patient monitoring instruments and offer diagnostic services in
the United States and Europe to veterinarians. Our principal executive offices
are located at 1613 Prospect Parkway, Fort Collins, Colorado 80525 and our
telephone number is (970) 493-7272.

                           FORWARD-LOOKING STATEMENTS

      This prospectus and the documents incorporated herein by reference contain
forward-looking statements within the meaning of Section 27A of the Securities
Act of 1933, as amended and Section 21E of the Exchange Act. Words such as
"anticipates," "expects," "intends," "plans," "believes," "seeks," "estimates,"
variations of such words and similar expressions are intended to identify such
forward- looking statements. These statements are not guarantees of future
performance and are subject to certain risks, uncertainties and assumptions that
are difficult to predict. Therefore, actual results could differ materially from
those expressed or forecasted in any such forward-looking statements as a result
of certain factors, including those set forth in "Risk Factors," as well as
those noted in the documents incorporated herein by reference. In connection
with forward-looking statements that appear in these disclosures, investors
should carefully review the factors set forth in this prospectus under "Risk
Factors."





                                  RISK FACTORS

      Our future operating results may vary substantially from period to period
due to a number of factors, many of which are beyond our control. The following
discussion highlights some of these factors and the possible impact of these
factors on future results of operations. You should carefully consider these
factors before making an investment decision. If any of the following factors
actually occur, our business, financial condition or results of operations could
be harmed. In that case, the price of our common stock could decline, and you
could experience losses on your investment.

WE ANTICIPATE FUTURE LOSSES AND NEGATIVE CASH FLOW.

      We have incurred net losses since our inception in 1988 and, as of
September 30, 2001, we had an accumulated deficit of $187.6 million. We
anticipate that we may continue to incur additional operating losses in the near
term. These losses have resulted principally from expenses incurred in our
research and development programs and from general and administrative and sales
and marketing expenses. Even if we achieve profitability, we may not be able to
sustain or increase profitability on a quarterly or annual basis. If we cannot
achieve or sustain profitability, we may not be able to meet our working capital
expenditures, which would have a material adverse effect on our business.

WE MAY NEED ADDITIONAL CAPITAL IN THE FUTURE AND WE CANNOT BE SURE THAT
ADDITIONAL FINANCING WILL BE AVAILABLE.

      We have incurred negative cash flow from operations since inception in
1988. We may not generate positive cash flow sufficient to fund our operations
in the near term and may need to raise additional capital through one or more of
the following:

      -  sale of additional equity or debt securities;

      -  sale of various assets;

      -  licensing of technology; and

      -  sale of various products or marketing rights.

      Additional capital may not be available on acceptable terms, if at all.
Furthermore, any additional equity financing would likely be dilutive to
stockholders, and additional debt financing, if available, may include
restrictive covenants which may limit our currently planned operations and
strategies. If adequate funds are not available, we may be required to curtail
our operations significantly and reduce discretionary spending to extend the
currently available cash resources, or to obtain funds by entering into
collaborative agreements or other arrangements on unfavorable terms, all of
which would likely have a material adverse effect on our business, financial
condition and our ability to reduce losses or generate profits.

WE HAVE LIMITED RESOURCES TO DEVOTE TO PRODUCT DEVELOPMENT AND
COMMERCIALIZATION. IF WE ARE NOT ABLE TO DEVOTE ADEQUATE RESOURCES TO PRODUCT
DEVELOPMENT AND COMMERCIALIZATION, WE MAY NOT BE ABLE TO DEVELOP OUR PRODUCTS.

      Our strategy is to develop a broad range of products addressing companion
animal healthcare. We believe that our revenue growth and profitability, if any,
will substantially depend upon our ability to:

      -  improve market acceptance of our current products;

      -  complete development of new products; and


                                                                             -2-


      -  successfully introduce and commercialize new products.

      We have introduced some of our products only recently and many of our
products are still under development. Because we have limited resources to
devote to product development and commercialization, any delay in the
development of one product or reallocation of resources to product development
efforts that prove unsuccessful may delay or jeopardize the development of our
other product candidates. If we fail to develop new products and bring them to
market, our ability to generate revenues will decrease.

      In addition, our products may not achieve satisfactory market acceptance,
and we may not successfully commercialize them on a timely basis, or at all. If
our products do not achieve a significant level of market acceptance, demand for
our products will not develop as expected and it is unlikely that we ever will
become profitable.

WE MUST OBTAIN AND MAINTAIN COSTLY REGULATORY APPROVALS IN ORDER TO MARKET OUR
PRODUCTS.

      Many of the products we develop and market are subject to extensive
regulation by one or more of the United States Department of Agriculture, or
USDA, the Food and Drug Administration, or FDA, the Environmental Protection
Agency, or EPA, and foreign regulatory authorities. These regulations govern,
among other things, the development, testing, manufacturing, labeling, storage,
premarket approval, advertising, promotion, sale and distribution of our
products. Satisfaction of these requirements can take several years and time
needed to satisfy them may vary substantially, based on the type, complexity and
novelty of the product. The effect of government regulation may be to delay or
to prevent marketing of our products for a considerable period of time and to
impose costly procedures upon our activities. We have experienced in the past,
and may experience in the future, difficulties that could delay or prevent us
from obtaining the regulatory approval or license necessary to introduce or
market our products. Regulatory approval of our products may also impose
limitations on the indicated or intended uses for which our products may be
marketed.

      Among the conditions for certain regulatory approvals is the requirement
that our manufacturing facilities or those of our third party manufacturers
conform to current Good Manufacturing Practices. The FDA and foreign regulatory
authorities strictly enforce Good Manufacturing Practices requirements through
periodic inspections. We can provide no assurance that any regulatory authority
will determine that our manufacturing facilities or those of our third party
manufacturers will conform to Good Manufacturing Practices requirements.
Failure to comply with applicable regulatory requirements can result in
sanctions being imposed on us or the manufacturers of our products, including
warning letters, product recalls or seizures, injunctions, refusal to permit
products to be imported into or exported out of the United States, refusals of
regulatory authorities to grant approval or to allow us to enter into
government supply contracts, withdrawals of previously approved marketing
applications, civil fines and criminal prosecutions.

FACTORS BEYOND OUR CONTROL MAY CAUSE OUR OPERATING RESULTS TO FLUCTUATE, AND
SINCE MANY OF OUR EXPENSES ARE FIXED, THIS FLUCTUATION COULD CAUSE OUR STOCK
PRICE TO DECLINE.

      We believe that our future operating results will fluctuate on a quarterly
basis due to a variety of factors, including:

      -  results from our Diamond Animal Health subsidiary;

      -  the introduction of new products by us or by our competitors;

      -  market acceptance of our current or new products;

      -  regulatory and other delays in product development;

      -  product recalls;



                                                                             -3-


      -  competition and pricing pressures from competitive products;

      -  manufacturing delays;

      -  shipment problems;

      -  product seasonality; and

      -  changes in the mix of products sold.

      We have high operating expenses for personnel, new product development and
marketing. Many of these expenses are fixed in the short term. If any of the
factors listed above cause our revenues to decline, our operating results could
be substantially harmed.

      Our operating results in some quarters may not meet the expectations of
stock market analysts and investors. In that case, our stock price probably
would decline.

WE MUST MAINTAIN VARIOUS FINANCIAL AND OTHER COVENANTS UNDER OUR REVOLVING LINE
OF CREDIT AGREEMENT.

      Under our revolving line of credit agreement with Wells Fargo Business
Credit, Inc., we are required to comply with various financial and non-financial
covenants, and we have made various representations and warranties. Among the
financial covenants are requirements for monthly minimum book net worth, minimum
quarterly net income and minimum cash balances or liquidity levels. Failure to
comply with any of the covenants, representations or warranties would negatively
impact our ability to borrow under the agreement. Our inability to borrow to
fund our operations could materially harm our business.

A SMALL NUMBER OF LARGE CUSTOMERS ACCOUNT FOR A LARGE PERCENTAGE OF OUR
REVENUES, AND THE LOSS OF ANY OF THEM COULD HARM OUR OPERATING RESULTS.

      We currently derive a substantial portion of our revenues from sales by
our subsidiary Diamond, which manufactures various of our products and products
for other companies in the animal health industry. Revenues from one Diamond
customer in 2001 and two Diamond customers in 2000 comprised approximately
15% and 41% of our total revenues for the three months ended September 30, 2001
and 2000, respectively, and 12% and 28% of our total revenues for the nine
months ended September 30, 2001 and 2000, respectively. If we are not
successful in maintaining our relationships with our customers and obtaining
new customers, our business and results of operations will suffer.

WE OPERATE IN A HIGHLY COMPETITIVE INDUSTRY, WHICH COULD RENDER OUR PRODUCTS
OBSOLETE OR SUBSTANTIALLY LIMIT THE VOLUME OF PRODUCTS THAT WE SELL. THIS WOULD
LIMIT OUR ABILITY TO COMPETE AND ACHIEVE PROFITABILITY.

      We compete with independent animal health companies and major
pharmaceutical companies that have animal health divisions. Companies with a
significant presence in the animal health market, such as American Home
Products, Bayer, IDEXX Laboratories, Inc., Intervet International B.V., Merial
Ltd., Novartis, Pfizer Inc., Pharmacia Animal Health and Schering Plough
Corporation, have developed or are developing products that compete with our
products or would compete with them if developed. These competitors may have
substantially greater financial, technical, research and other resources and
larger, better-established marketing, sales, distribution and service
organizations than us. In addition, IDEXX, which has products that compete with
our heartworm diagnostic products, prohibits its distributors from selling
competitors' products, including ours. Our competitors frequently offer broader
product lines and have greater name recognition than we do. Our competitors may
develop or market technologies or products that are more effective or
commercially attractive than our current or future products or that would render
our technologies and products obsolete. Further, additional competition could
come from new entrants to the animal healthcare market. Moreover, we may not
have the financial resources, technical expertise or marketing, distribution or


                                                                             -4-


support capabilities to compete successfully. If we fail to compete
successfully, our ability to achieve profitability will be limited.

WE HAVE LIMITED EXPERIENCE IN MARKETING OUR PRODUCTS, AND MAY BE UNABLE TO
COMMERCIALIZE OUR PRODUCTS.

      The market for companion animal healthcare products is highly fragmented,
with discount stores and specialty pet stores accounting for a substantial
percentage of sales. Because we sell our companion animal health products only
to veterinarians, we may fail to reach a substantial segment of the potential
market, and we may not be able to offer our products at prices which are
competitive with those of companies that distribute their products through
retail channels. We currently market our products to veterinarians through
independent third party distributors and through a direct sales force. To be
successful, we will have to continue to develop and train our direct sales
force or rely on other arrangements with third parties to market, distribute
and sell our products. We may not successfully develop and maintain marketing,
distribution or sales capabilities, and we may not be able to make arrangements
with third parties to perform these activities on satisfactory terms. If we
fail to develop a successful marketing strategy, our ability to commercialize
our products and generate revenues will decrease.

WE HAVE GRANTED THIRD PARTIES SUBSTANTIAL MARKETING RIGHTS TO OUR PRODUCTS UNDER
DEVELOPMENT. IF OUR CURRENT THIRD PARTY MARKETING AGREEMENTS ARE NOT SUCCESSFUL,
OR IF WE ARE UNABLE TO DEVELOP OUR OWN MARKETING CAPABILITIES OR ENTER INTO
ADDITIONAL MARKETING AGREEMENTS IN THE FUTURE, WE MAY NOT BE ABLE TO DEVELOP AND
COMMERCIALIZE OUR PRODUCTS.

      Our agreements with our corporate marketing partners generally contain no
minimum purchase requirements in order for them to maintain their exclusive or
co-exclusive marketing rights. Novartis or Ralston Purina or any other
collaborative party may not devote sufficient resources to marketing our
products. Furthermore, there is nothing to prevent Novartis or Ralston
Purina or any other collaborative party from pursuing alternative technologies
or products that may compete with our products. If we fail to develop and
maintain our own marketing capabilities, we may find it necessary to continue to
rely on potential or actual competitors for third party marketing assistance.
Third party marketing assistance may not be available in the future on
reasonable terms, if at all. If any of these events occur, we may not be able to
develop and commercialize our products and our revenues will decline.

WE MAY FACE COSTLY INTELLECTUAL PROPERTY DISPUTES.

      Our ability to compete effectively will depend in part on our ability to
develop and maintain proprietary aspects of our technology and either to operate
without infringing the proprietary rights of others or to obtain rights to
technology owned by third parties. We have United States and foreign-issued
patents and are currently prosecuting patent applications in the United States
and with various foreign countries. Our pending patent applications may not
result in the issuance of any patents or any issued patents that will offer
protection against competitors with similar technology. Patents we receive may
be challenged, invalidated or circumvented in the future or the rights created
by those patents may not provide a competitive advantage. We also rely on trade
secrets, technical know-how and continuing invention to develop and maintain our
competitive position. Others may independently develop substantially equivalent
proprietary information and techniques or otherwise gain access to our trade
secrets.

      The biotechnology and pharmaceutical industries have been characterized by
extensive litigation relating to patents and other intellectual property rights.
In 1998, Synbiotics Corporation filed a lawsuit against us alleging infringement
of a Synbiotics patent relating to heartworm diagnostic technology, and this
litigation remains ongoing. We may become subject to additional patent
infringement claims and litigation in the United States or other countries or
interference proceedings conducted in the United States Patent and


                                                                             -5-


Trademark Office to determine the priority of inventions. The defense and
prosecution of intellectual property suits, USPTO interference proceedings, and
related legal and administrative proceedings are costly, time-consuming and
distracting. We may also need to pursue litigation to enforce any patents issued
to us or our collaborative partners, to protect trade secrets or know-how owned
by us or our collaborative partners, or to determine the enforceability, scope
and validity of the proprietary rights of others. Any litigation or interference
proceeding will result in substantial expense to us and significant diversion of
the efforts of our technical and management personnel. Any adverse determination
in litigation or interference proceedings could subject us to significant
liabilities to third parties. Further, as a result of litigation or other
proceedings, we may be required to seek licenses from third parties which may
not be available on commercially reasonable terms, if at all.

      We license technology from a number of third parties. The majority of
these license agreements impose due diligence or milestone obligations on us,
and in some cases impose minimum royalty and/or sales obligations on us, in
order for us to maintain our rights under these agreements. Our products may
incorporate technologies that are the subject of patents issued to, and patent
applications filed by, others. As is typical in our industry, from time to time
we and our collaborators have received, and may in the future receive, notices
from third parties claiming infringement and invitations to take licenses under
third party patents. It is our policy that when we receive such notices, we
conduct investigations of the claims they assert. With respect to the notices we
have received to date, we believe, after due investigation, that we have
meritorious defenses to the infringement claims asserted. Any legal action
against us or our collaborators may require us or our collaborators to obtain
one or more licenses in order to market or manufacture affected products or
services. However, we or our collaborators may not be able to obtain licenses
for technology patented by others on commercially reasonable terms, we may not
be able to develop alternative approaches if unable to obtain licenses, or
current and future licenses may not be adequate for the operation of our
businesses. Failure to obtain necessary licenses or to identify and implement
alternative approaches could prevent us and our collaborators from
commercializing our products under development and could substantially harm our
business.

WE HAVE LIMITED MANUFACTURING EXPERIENCE AND CAPACITY AND RELY SUBSTANTIALLY ON
THIRD PARTY MANUFACTURERS. THE LOSS OF ANY THIRD PARTY MANUFACTURERS COULD LIMIT
OUR ABILITY TO LAUNCH OUR PRODUCTS IN A TIMELY MANNER, OR AT ALL.

      To be successful, we must manufacture, or contract for the manufacture of,
our current and future products in compliance with regulatory requirements, in
sufficient quantities and on a timely basis, while maintaining product quality
and acceptable manufacturing costs. In order to increase our manufacturing
capacity, we acquired Diamond in April 1996.

      We currently rely on third parties to manufacture those products we do not
manufacture at our Diamond facility. We currently have supply agreements with
Quidel Corporation for various manufacturing services relating to our
point-of-care diagnostic tests, with Centaq, Inc. for the manufacture of our own
allergy immunotherapy treatment products and with various manufacturers for the
supply of our veterinary diagnostic and patient monitoring instruments. Our
manufacturing strategy presents the following risks:

      -  Delays in the scale-up to quantities needed for product development
         could delay regulatory submissions and commercialization of our
         products in development;

      -  Our manufacturing facilities and those of some of our third party
         manufacturers are subject to ongoing periodic unannounced inspection by
         regulatory authorities, including the FDA, USDA and other federal and
         state agencies for compliance with strictly enforced Good Manufacturing
         Practices regulations and similar foreign standards, and we do not have
         control over our third party manufacturers' compliance with these
         regulations and standards;



                                                                             -6-


      -  If we need to change to other commercial manufacturing contractors for
         certain of our products, additional regulatory licenses or approvals
         must be obtained for these contractors prior to our use. This would
         require new testing and compliance inspections. Any new manufacturer
         would have to be educated in, or develop substantially equivalent
         processes necessary for the production of our products;

      -  If market demand for our products increases suddenly, our current
         manufacturers might not be able to fulfill our commercial needs, which
         would require us to seek new manufacturing arrangements and may result
         in substantial delays in meeting market demand; and

      -  We may not have intellectual property rights, or may have to share
         intellectual property rights, to any improvements in the manufacturing
         processes or new manufacturing processes for our products.

      Any of these factors could delay commercialization of our products under
development, interfere with current sales, entail higher costs and result in our
being unable to effectively sell our products.

      Our agreements with various suppliers of the veterinary medical
instruments require us to meet minimum annual sales levels to maintain our
position as the exclusive distributor of these instruments. We may not meet
these minimum sales levels in the future, and maintain exclusivity over the
distribution and sale of these products. If we are not the exclusive distributor
of these products, competition may increase.

WE DEPEND ON PARTNERS IN OUR RESEARCH AND DEVELOPMENT ACTIVITIES. IF OUR CURRENT
PARTNERSHIPS AND COLLABORATIONS ARE NOT SUCCESSFUL, WE MAY NOT BE ABLE TO
DEVELOP OUR TECHNOLOGIES OR PRODUCTS.

      For several of our proposed products, we are dependent on collaborative
partners to successfully and timely perform research and development activities
on our behalf. These collaborative partners may not complete research and
development activities on our behalf in a timely fashion, or at all. If our
collaborative partners fail to complete research and development activities, or
fail to complete them in a timely fashion, our ability to develop technologies
and products will be impacted negatively and our revenues will decline.

WE DEPEND ON KEY PERSONNEL FOR OUR FUTURE SUCCESS. IF WE LOSE OUR KEY PERSONNEL
OR ARE UNABLE TO ATTRACT AND RETAIN ADDITIONAL PERSONNEL, WE MAY BE UNABLE TO
ACHIEVE OUR GOALS.

      Our future success is substantially dependent on the efforts of our senior
management and scientific team. The loss of the services of members of our
senior management or scientific staff may significantly delay or prevent the
achievement of product development and other business objectives. Because of the
specialized scientific nature of our business, we depend substantially on our
ability to attract and retain qualified scientific and technical personnel.
There is intense competition among major pharmaceutical and chemical companies,
specialized biotechnology firms and universities and other research institutions
for qualified personnel in the areas of our activities. If we lose the services
of, or fail to recruit, key scientific and technical personnel, the growth of
our business could be substantially impaired.

WE MAY FACE PRODUCT RETURNS AND PRODUCT LIABILITY LITIGATION AND THE EXTENT OF
OUR INSURANCE COVERAGE IS LIMITED. IF WE BECOME SUBJECT TO PRODUCT LIABILITY
CLAIMS RESULTING FROM DEFECTS IN OUR PRODUCTS, WE MAY FAIL TO ACHIEVE MARKET
ACCEPTANCE OF OUR PRODUCTS AND OUR BUSINESS COULD BE HARMED.

      The testing, manufacturing and marketing of our current products as well
as those currently under development entail an inherent risk of product
liability claims and associated adverse publicity. Following the introduction of
a product, adverse side effects may be discovered. Adverse publicity regarding
such effects could affect sales of our other products for an indeterminate time
period. To date, we have not experienced any material product liability claims,
but any claim arising in the future could substantially harm our business.
Potential product liability claims may exceed the amount of our insurance
coverage or may be excluded from


                                      -7-


coverage under the terms of the policy. We may not be able to continue to obtain
adequate insurance at a reasonable cost, if at all. In the event that we are
held liable for a claim against which we are not indemnified or for damages
exceeding the $10 million limit of our insurance coverage or which results in
significant adverse publicity against us, we may lose revenue and fail to
achieve market acceptance.

WE MAY BE HELD LIABLE FOR THE RELEASE OF HAZARDOUS MATERIALS, WHICH COULD RESULT
IN EXTENSIVE CLEAN UP COSTS OR OTHERWISE HARM OUR BUSINESS.

      Our products and development programs involve the controlled use of
hazardous and biohazardous materials, including chemicals, infectious disease
agents and various radioactive compounds. Although we believe that our safety
procedures for handling and disposing of such materials comply with the
standards prescribed by applicable local, state and federal regulations, we
cannot completely eliminate the risk of accidental contamination or injury from
these materials. In the event of such an accident, we could be held liable for
any fines, penalties, remediation costs or other damages that result. Our
liability for the release of hazardous materials could exceed our resources,
which could lead to a shutdown of our operations. In addition, we may incur
substantial costs to comply with environmental regulations as we expand our
manufacturing capacity.

WE EXPECT TO EXPERIENCE VOLATILITY IN OUR STOCK PRICE, WHICH MAY AFFECT OUR
ABILITY TO RAISE CAPITAL IN THE FUTURE OR MAKE IT DIFFICULT FOR INVESTORS TO
SELL THEIR SHARES.

      The securities markets have experienced significant price and volume
fluctuations and the market prices of securities of many public biotechnology
companies have in the past been, and can in the future be expected to be,
especially volatile. For example, in the last twelve months our closing stock
price has ranged from a low of $0.53 to a high of $1.47. Fluctuations in the
trading price or liquidity of our common stock may adversely affect our ability
to raise capital through future equity financings. Factors that may have a
significant impact on the market price and marketability of our common stock
include:

      -  announcements of technological innovations or new products by us or by
         our competitors;

      -  our quarterly operating results;

      -  releases of reports by securities analysts;

      -  developments or disputes concerning patents or proprietary rights;

      -  regulatory developments;

      -  developments in our relationships with collaborative partners;

      -  changes in regulatory policies;

      -  litigation;

      -  economic and other external factors; and

      -  general market conditions.

      In the past, following periods of volatility in the market price of a
company's securities, securities class action litigation has often been
instituted. If a securities class action suit is filed against us, we would
incur substantial legal fees and our management's attention and resources would
be diverted from operating our business in order to respond to the litigation.

IF WE FAIL TO MEET NASDAQ NATIONAL MARKET LISTING REQUIREMENTS, OUR COMMON STOCK
MAY BE DELISTED AND BECOME ILLIQUID.

      Our common stock is currently listed on the Nasdaq National Market. Nasdaq
has requirements we must meet in order to remain listed on the Nasdaq National
Market. If we continue to experience losses from our operations or we are unable
to raise additional funds as needed, we might not be able to maintain the
standards for continued quotation on the Nasdaq National Market, including a
minimum bid price


                                                                             -8-


requirement of $1.00. As of the date of this prospectus, our minimum bid price
was above $1.00. If the minimum bid price of our common stock were to drop
below $1.00 and remain below $1.00 for 30 consecutive trading days, or if we
were unable to continue to meet Nasdaq's standards for any other reason, our
common stock could be delisted from the Nasdaq National Market.

      If as a result of the application of these listing requirements, our
common stock were delisted from the Nasdaq National Market, our stock would
become harder to buy and sell. Further, our stock could be subject to what are
known as the "penny stock" rules. The penny stock rules place additional
requirements on broker-dealers who sell or make a market in such securities.
Consequently, if we were removed from the Nasdaq National Market, the ability or
willingness of broker-dealers to sell or make a market in our common stock might
decline. As a result, the ability for investors to resell shares of our common
stock could be adversely affected.

THE COMMON STOCK SOLD IN THIS OFFERING WILL INCREASE THE SUPPLY OF OUR COMMON
STOCK ON THE PUBLIC MARKET, WHICH MAY CAUSE OUR STOCK PRICE TO DECLINE.

      The sale into the public market of the common stock to be sold in this
offering could adversely affect the market price of our common stock. Most of
our shares of common stock outstanding are eligible for immediate and
unrestricted sale in the public market at any time. Once the registration
statement of which this prospectus forms a part is declared effective, the
7,792,768 shares of common stock covered by this prospectus will be eligible for
immediate and unrestricted resale into the public market. The presence of these
additional shares of common stock in the public market may further depress our
stock price.

                                 USE OF PROCEEDS

      Heska will not receive any of the proceeds from the sale of the shares
offered by this prospectus. All proceeds from the sale of the shares offered
hereby will be for the account of the selling stockholders, as described below.
See "Selling Stockholders" and "Plan of Distribution."







                                                                             -9-


                              SELLING STOCKHOLDERS

      The following table sets forth as of January 7, 2002, the name of each of
the selling stockholders, the number of shares of common stock that each selling
stockholder owns, the number of shares of common stock owned by each selling
stockholder that may be offered for sale from time to time by this prospectus,
and the number of shares of common stock to be held by each selling stockholder
assuming the sale of all the common stock offered hereby.

      Some of the selling stockholders may distribute their shares, from time to
time, to their limited and/or general partners, who may sell shares pursuant to
this prospectus. Each selling stockholder may also transfer shares owned by him
by gift, and upon any such transfer the donee would have the same right of sale
as the selling stockholder.

      The shares being offered by the selling stockholders were acquired in
connection with a private placement on December 18, 2001. Except as set forth
below, none of the selling stockholders has had a material relationship with us
within the past three years other than as a result of the ownership of our
common stock. We may amend or supplement this prospectus from time to time to
update the disclosure set forth herein.



                                                SHARES            NUMBER OF           SHARES
                                             BENEFICIALLY          SHARES           BENEFICIALLY
                                            OWNED PRIOR TO          BEING           OWNED AFTER
NAME OF SELLING STOCKHOLDER                   OFFERING(1)          OFFERED         OFFERING(1)(2)
---------------------------               --------------------    ---------     --------------------
                                           NUMBER      PERCENT                   NUMBER      PERCENT
                                          ---------    -------                  ---------    -------
                                                                              
State of Wisconsin Investment Board .     8,286,182     17.37%    1,818,182     6,468,000     13.56%
Charter Ventures II, L.P.(3) ........     8,414,717     17.64%    2,207,793     6,206,924     13.01%
Lombard Odier & Cie(4) ..............     3,423,551      7.18%      649,351     2,774,200      5.82%
FSVK Investment Inc. ................       259,741        *        259,741             0        *
Rhino Capital LLC ...................       259,741        *        259,741             0        *
A. Carey Zesiger(5) .................        32,000        *         26,000         6,000        *
Alexa Zesiger Carver(5) .............        32,000        *         26,000         6,000        *
Albert L. Zesiger(5) ................       352,000        *        130,000       222,000        *
Asphalt Green, Inc. (5) .............        32,000        *         32,000             0        *
Barrie Ramsay Zesiger(5) ............       250,000        *        117,000       133,000        *
David Zesiger(5) ....................        31,000        *         19,000        12,000        *
HBL Charitable Unitrust(5) ..........        70,000        *         32,000        38,000        *
Psychology Associates(5) ............        90,000        *         32,000        58,000        *
Lazar Foundation(5) .................       115,000        *         52,000        63,000        *
Peter Looram(5) .....................       138,000        *         65,000        73,000        *
Mary C. Anderson (5)(6) .............       142,000        *         65,000        77,000        *
Murray Capital, LLC(5) ..............        70,000        *         32,000        38,000        *
NFIB Corporate Account(5) ...........       314,000        *        162,000       152,000        *
Nicola Zesiger Mullen(5) ............        39,000        *         32,000         7,000        *
Norwalk Employees' Pension Plan(5) ..       479,000      1.00%      221,000       258,000        *
Public Employee Retirement System of
  Idaho(5) ..........................     2,174,960      4.56%    1,038,960     1,135,000      2.38%
City of Stamford Firemen's Pension
  Fund(5) ...........................       320,000        *        182,000       138,000        *
Theeuwes Family Trust, Felix Theeuwes
  Trustee(5) ........................       143,000        *         66,000        77,000        *
Alan B. & Joanne K. Vidinsky 1993
  Trust(5) ..........................        66,000        *         66,000             0        *
Wells Family LLC(5) .................       433,000        *        202,000       231,000        *


----------

* Represents less than 1% of our common stock.

(1)  Based on 47,698,175 shares outstanding as of December 18, 2001.



                                                                            -10-


(2)  Assumes that each selling stockholder sells all shares registered under
     this registration statement. However, to our knowledge, there are no
     agreements, arrangements or understandings with respect to the sale of any
     of our common stock, and each selling stockholder may decide not to sell
     his shares that are registered under this registration statement.

(3)  Represents 3,386,510 shares and options to purchase 1,000 shares of our
     common stock held by Charter Ventures and 5,026,207 shares and options to
     purchase 1,000 shares of our common stock held by Charter Ventures II,
     L.P., with respect to which Mr. A. Barr Dolan, one of our directors,
     disclaims beneficial ownership except to the extent of his proportionate
     share therein. Mr. Dolan is a general partner of each of Charter Ventures
     and Charter Ventures II, L.P., and may be deemed a beneficial owner of the
     shares held by such entities because of shared voting power with respect to
     such shares.

(4)  Shares listed consist of 2,755,000 shares held as custodian for the Lombard
     Odier Nutrition Fund, over which Lombard Odier & Cie and Lombard Odier Fund
     Managers S.A. share voting and dispositive power, and 19,200 shares held
     for the benefit of private and institutional clients. Such clients have the
     right to receive or the power to direct the receipt of dividends from, or
     the proceeds from the sale of, such shares and retain sole voting power
     with respect to such shares.

(5)  Zesiger Capital Group LLC acted as the agent and attorney-in-fact for this
     selling stockholder in connection with the stockholder's acquisition from
     us of the shares offered by this selling stockholder under this prospectus.
     Zesiger Capital Group LLC is an investment adviser registered with the
     Securities and Exchange Commission under the Investment Advisers Act of
     1940. This selling stockholder is an advisory client of Zesiger Capital
     Group LLC, and the shares offered by this selling stockholder under this
     prospectus are held in a discretionary client account managed by Zesiger
     Capital Group LLC. Zesiger Capital Group LLC disclaims beneficial ownership
     of these shares.

(6)  Includes 77,000 shares owned by Ms. Anderson individually and 65,000 shares
     offered under this prospectus by the Mary C. Anderson Revocable Trust dtd
     7/6/99, for which Ms. Anderson is the trustee.






                                                                            -11-



                              PLAN OF DISTRIBUTION

      We are registering 7,792,768 shares of Common Stock, par value of $0.001
per share on behalf of certain selling stockholders. We will receive no proceeds
from this offering. The shares may be offered by certain of our stockholders or
by pledgees, donees, transferees or other successors in interest that receive
such shares as a gift, partnership distribution or other non-sale related
transfer. We originally issued the shares in connection with the Share Purchase
Agreement between Heska and the selling stockholders, dated December 13, 2001.
We are registering the shares pursuant to the Share Purchase Agreement. The
shares were issued pursuant to exemptions from the registration requirements of
the Securities Act, provided by Section 4(2) thereof.

      The selling stockholders will act independently of Heska in making
decisions with respect to the timing, manner and size of each sale. The selling
stockholders may sell the shares on the Nasdaq National Market, or otherwise, at
prices and under terms then prevailing or at prices related to the then current
market price, at varying prices or at negotiated prices. The shares may be sold,
without limitation, by one or more of the following means of distribution:

      -  a block trade in which the broker-dealer so engaged will attempt to
         sell such shares as agent, but may position and resell a portion of the
         block as principal to facilitate the transaction;

      -  purchases by a broker-dealer as principal and resale by such
         broker-dealer for its own account pursuant to this prospectus;

      -  an over-the-counter distribution in accordance with the rules of the
         Nasdaq National Market;

      -  ordinary brokerage transactions and transactions in which the broker
         solicits purchasers; and

      -  in privately negotiated transactions. To the extent required, this
         prospectus may be amended and supplemented from time to time to
         describe a specific plan of distribution.

      In connection with distributions of the shares or otherwise, the selling
stockholders may enter into hedging transactions with broker-dealers or other
financial institutions. In connection with such transactions, broker-dealers or
other financial institutions may engage in short sales of the shares in the
course of hedging the positions they assume with selling stockholders. The
selling stockholders may also sell the shares short and redeliver the shares to
close out such short positions. The selling stockholders may also enter into
option or other transactions with broker-dealers or other financial institutions
which require the delivery to such broker-dealer or other financial institution
of the shares, which shares such broker-dealer or other financial institution
may resell or otherwise transfer pursuant to this prospectus (as supplemented or
amended to reflect such transaction). The selling stockholders may also pledge
the shares to a broker-dealer or other financial institution, and, upon a
default, such broker-dealer or other financial institution, may effect sales of
the pledged shares pursuant to this prospectus (as supplemented or amended to
reflect such transaction). In addition, any shares that qualify for sale
pursuant to Rule 144 may, at the option of the holder thereof, be sold under
Rule 144 rather than pursuant to this prospectus.

      Any broker-dealer participating in such transactions as agent may receive
commissions from the selling stockholders and/or purchasers of the shares (and,
if it acts as agent for the purchaser of such shares, from such purchaser).
Usual and customary brokerage fees will be paid by the selling stockholders.
Broker-dealers may agree with the selling stockholders to sell a specified
number of shares at a stipulated price per share, and, to the extent such a
broker-dealer is unable to do so acting as agent for the selling stockholders,
to


                                                                            -12-


purchase as principal any unsold shares at the price required to fulfill the
broker-dealer commitment to the selling stockholders. Broker-dealers who acquire
shares as principal may thereafter resell such shares from time to time in
transactions (which may involve cross and block transactions and which may
involve sales to and through other broker-dealers, including transactions of the
nature described above) in the over-the-counter market, in negotiated
transactions or otherwise at market prices prevailing at the time of sale or at
negotiated prices, and in connection with such resales, may pay to or receive
from the purchasers of such shares commissions computed as described above. Such
broker-dealers and any other participating broker-dealers or the selling
stockholders may be deemed to be "underwriters" within the meaning of Section
2(11) of the Securities Act in connection with such sales and any such
commission, discount or concession may be deemed to be underwriting discounts or
commissions under the Securities Act. Because the selling stockholders may be
deemed to be an underwriter under Section 2(11) of the Securities Act, the
selling stockholders will be subject to the prospectus delivery requirements of
the Securities Act.

      To comply with the securities laws of certain states, if applicable, the
shares will be sold in such jurisdictions only through registered or licensed
brokers or dealers. In addition, in certain states the shares may not be sold
unless they have been registered or qualified for sale in the applicable state
or an exemption from the registration or qualification requirement is available
and is complied with.

      Under applicable rules and regulations under the Exchange Act, any persons
engaged in the distribution of the shares may not simultaneously engage in
market making activities with respect to our common stock for a period of two
business days prior to the commencement of such distribution. In addition and
without limiting the foregoing, each selling stockholder will be subject to
applicable provisions of the Exchange Act and the associated rules and
regulations thereunder, including, without limitation, Regulation M, which
provisions may limit the timing of purchases and sales of shares of our common
stock by the selling stockholders. We will make copies of this prospectus
available to the selling stockholders and have informed them of the need for
delivery of copies of this prospectus to purchasers at or prior to the time of
any sale of the shares. We assume no obligation to so deliver copies of this
prospectus or any related prospectus supplement.

      At the time a particular offer of shares is made, if required, a
prospectus supplement will be distributed that will set forth the number of
shares being offered and the terms of the offering, including the name of any
underwriter, dealer or agent, the purchase price paid by any underwriter, any
discount, commission and other item constituting compensation, any discount,
commission or concession allowed or reallowed or paid to any dealer, and the
proposed selling price to the public.

      The selling stockholders will be responsible for any fees, disbursements
and expenses of any counsel for the selling stockholders. We will bear all other
expenses incurred in connection with the registration of the shares, including
printer's and accounting fees and the fees, disbursements and expenses of
counsel for us up to a certain amount. Commissions and discounts, if any,
attributable to the sales of the shares will be borne by the selling
stockholders. The selling stockholders may agree to indemnify any broker-dealer
that participates in transactions involving sales of the shares against certain
liabilities, including liabilities arising under the Securities Act. We will
indemnify the selling stockholders against claims arising out of any untrue
statement of a material fact contained in this Registration Statement or any
omission to state therein a material fact necessary in order to make the
statement made therein not misleading.

      We have undertaken to keep a Registration Statement of which this
prospectus constitutes a part effective until the earlier of the disposition of
the securities offered hereby or two years measured from the effective date of
this Registration Statement. After such period, if we choose not to maintain the
effectiveness of the Registration Statement of which this prospectus constitutes
a part, the securities issuable offered hereby may not be sold, pledged,
transferred or assigned, except in a transaction which is exempt under the
provisions of the Securities Act or pursuant to an effective registration
statement thereunder.



                                                                            -13-


                                  LEGAL MATTERS

      Certain legal matters relating to the validity of the securities offered
hereby will be passed upon for us by Wilson Sonsini Goodrich & Rosati,
Professional Corporation, San Francisco, California.

                                     EXPERTS

      The financial statements incorporated by reference in this prospectus have
been audited by Arthur Andersen LLP, independent public accountants, as
indicated in their reports with respect thereto, and are included herein in
reliance upon the authority of said firm as experts in giving said reports.

                       WHERE YOU CAN FIND MORE INFORMATION

      We file annual, quarterly and special reports, proxy statements and other
information with the Securities and Exchange Commission. You may read and copy
any document we file at the SEC's Public Reference Rooms in Washington, D.C.,
New York, New York and Chicago, Illinois. The Public Reference Room in
Washington, D.C. is located at 450 Fifth Street, N.W. Please call the SEC at
1-800-SEC-0330 for further information on the public conference rooms. Our SEC
filings are also available to the public from the SEC's web site at
http://www.sec.gov.

      The SEC allows us to "incorporate by reference" the information we file
with them, which means that we can disclose important information to you by
referring you to those documents. The information incorporated by reference is
considered to be part of this prospectus, and later information filed with the
SEC will update and supersede this information. We incorporate by reference the
documents listed below and any future filings made with the SEC under Section
13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934 until our
offering is completed.

      (1)   Our Annual Report on Form 10-K, for the year ended December 31,
            2000;

      (2)   Our Quarterly Reports on Form 10-Q for the quarters ended March 31,
            2001, June 30, 2001 and September 30, 2001;

      (3)   Our Current Reports on Form 8-K filed with the Securities and
            Exchange Commission on February 7, 2001 and December 20, 2001; and

      (4)   The description of our Common Stock contained in our Registration
            Statement on Form 8-A, filed with the Securities and Exchange
            Commission on April 24, 1997, and any further amendment or report
            filed hereafter for the purpose of updating any such description.

      You may request a copy of these filings, at no cost, by writing or
telephoning us at the following address:

                                Heska Corporation
                              1613 Prospect Parkway
                          Fort Collins, Colorado 80525
                                 (970) 493-7272

      You should rely only on the information incorporated by reference or
provided in this prospectus or the prospectus supplement. We have authorized no
one to provide you with different information. We are not making an offer of
these securities in any state where the offer is not permitted. You should not
assume that the information in this prospectus or the prospectus supplement is
accurate as of any date other than the date on the front of the document.



                                      -14-


      PROSPECTIVE INVESTORS MAY RELY ONLY ON THE INFORMATION CONTAINED IN THIS
PROSPECTUS. NEITHER HESKA NOR ANY SELLING STOCKHOLDERS HAS AUTHORIZED ANYONE TO
PROVIDE PROSPECTIVE INVESTORS WITH INFORMATION DIFFERENT FROM THAT CONTAINED IN
THIS PROSPECTUS. THIS PROSPECTUS IS NOT AN OFFER TO SELL NOR IS IT SEEKING AN
OFFER TO BUY THE SHARES IN ANY JURISDICTION WHERE THE OFFER OR SALE IS NOT
PERMITTED. THE INFORMATION CONTAINED IN THIS PROSPECTUS IS CORRECT ONLY AS OF
THE DATE OF THIS PROSPECTUS, REGARDLESS OF THE TIME OF THE DELIVERY OF THIS
PROSPECTUS OR ANY SALE OF THE SHARES.







                                HESKA CORPORATION

                                7,792,768 SHARES
                                  COMMON STOCK


                           ---------------------------

                                   PROSPECTUS

                           ---------------------------


                                          , 2002



                                     PART II

                     INFORMATION NOT REQUIRED IN PROSPECTUS

ITEM 14. OTHER EXPENSES OF ISSUANCE AND DISTRIBUTION

      The Company will pay all expenses incident to the offering and sale to the
public of the shares being registered other than any commissions and discounts
of underwriters, dealers or agents and any transfer taxes. Such expenses are set
forth in the following table. All of the amounts shown are estimates except for
the Securities and Exchange Commission registration fee.


                                              
            SEC Registration Fee...........      $    2,440
            Accounting fees and expenses...          15,000
            Legal fees and expenses........         100,000
            Miscellaneous..................           5,560
                                                 ----------
                 Total.....................      $  123,000
                                                 ==========


ITEM 15. INDEMNIFICATION OF DIRECTORS AND OFFICERS

   Section 145 of the Delaware General Corporation Law allows for the
indemnification of officers, directors and any corporate agents in terms
sufficiently broad to indemnify such persons under certain circumstances for
liabilities (including reimbursement for expenses incurred) arising under the
Securities Act. Our certificate of incorporation and our bylaws provide for
indemnification of our directors, officers, employees and other agents to the
extent and under the circumstances permitted by the Delaware General Corporation
Law. We have also entered into agreements with our directors and executive
officers that require Heska, among other things, to indemnify them against
certain liabilities that may arise by reason of their status or service as
directors and executive officers to the fullest extent permitted by Delaware
law. We have also purchased directors and officers liability insurance, which
provides coverage against certain liabilities including liabilities under the
Securities Act.

ITEM 16. EXHIBITS

                                  EXHIBIT INDEX



    EXHIBIT
    NUMBER    NOTES                             DESCRIPTION
    ------    -----   ----------------------------------------------------------
                
      5.1             Opinion of Wilson Sonsini Goodrich & Rosati, Professional
                      Corporation
     10.1             Share Purchase Agreement dated December 13, 2001
                      (incorporated by reference to the Current Report on Form
                      8-K filed by the Registrant on December 20, 2001)
     23.1             Consent of Wilson Sonsini Goodrich & Rosati, Professional
                      Corporation (included in Exhibit 5.1)
     23.2             Consent of Arthur Andersen LLP, independent accountants
     24.1             Power of Attorney (contained on Page II-4)



ITEM 17. UNDERTAKINGS

(a)   The undersigned Registrant hereby undertakes:

      (1)   To file, during any period in which offers or sales are being made,
a post-effective amendment to this Registration Statement:



                                                                            II-1


            (i)   To include any prospectus required by Section 10(a)(3) of the
                  Securities Act of 1933, as amended (the "Securities Act");

            (ii)  To reflect in the prospectus any facts or events arising after
                  the effective date of the registration statement (or the most
                  recent post-effective amendment thereof) which, individually
                  or in the aggregate, represent a fundamental change in the
                  information set forth in the registration statement.
                  Notwithstanding the foregoing, any increase or decrease in
                  volume of securities offered (if the total dollar value of
                  securities offered would not exceed that which was registered)
                  and any deviation from the low or high end of the estimated
                  maximum offering range may be reflected in the form of
                  prospectus filed with the Securities and Exchange Commission
                  pursuant to Rule 424(b) if, in the aggregate, the changes in
                  volume and price represent no more than a 20 percent change in
                  the maximum aggregate offering price set forth in the
                  "Calculation of Registration Fee" table in the effective
                  registration statement;

            (iii) To include any material information with respect to the plan
                  of distribution not previously disclosed in the Registration
                  Statement or any material change to such information in the
                  Registration Statement; provided, however, that paragraphs
                  (a)(1)(i) and (a)(1)(ii) above do not apply if the information
                  required to be included in a post-effective amendment by those
                  paragraphs is contained in the periodic reports filed by the
                  Registrant pursuant to Section 13 or Section 15(d) of the
                  Securities Exchange Act of 1934 (the "Exchange Act") that are
                  incorporated by reference into this Registration Statement.

      (2)   That, for the purpose of determining any liability under the
Securities Act, each such post-effective amendment shall be deemed to be a new
Registration Statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

      (3)   To remove from registration by means of a post-effective amendment
any of the securities being registered which remain unsold at the termination of
the offering.

(b)   The undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act, each filing of the
Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act that is incorporated by reference in the Registration Statement
shall be deemed to be a new Registration Statement relating to the securities
offered therein, and the offering of such securities at that time shall be
deemed to be the initial bona fide offering thereof.

(c)   Insofar as indemnification for liabilities arising under the Securities
Act may be permitted to directors, officers and controlling persons of the
Registrant pursuant to the foregoing provisions, or otherwise, the Registrant
has been advised that in the opinion of the Securities and Exchange Commission
such indemnification is against public policy as expressed in the Securities Act
and is, therefore, unenforceable. In the event that a claim for indemnification
against such liabilities (other than the payment by the Registrant of expenses
incurred or paid by a director, officer or controlling person of the Registrant
in the successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the Registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Securities Act and will be governed by the final
adjudication of such issue.



                                                                            II-2


(d)   The undersigned Registrant hereby undertakes that:

      (1)   for purposes of determining any liability under the Securities Act,
the information omitted from the form of prospectus filed as part of this
registration statement in reliance upon Rule 430A and contained in a form of
prospectus filed by the Registrant pursuant to Rule 424(b)(1) or (4) or 497(h)
under the Securities Act shall be deemed to be part of this Registration
Statement as of the time it was declared effective.

      (2)   for the purpose of determining liability under the Securities Act,
each post-effective amendment that contains a form of prospectus shall be deemed
to be a new registration statement relating to the securities offered therein,
and the offering of such securities at that time shall be deemed to be the
initial bona fide offering thereof.








                                                                            II-3


                                   SIGNATURES

      Pursuant to the requirements of the Securities Act of 1933, the Registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-3 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Fort Collins, State of Colorado, on January 7, 2002.

                                          HESKA CORPORATION


                                          By: /s/ Robert B. Grieve
                                              --------------------------------
                                              Robert B. Grieve
                                              Chief Executive Officer and
                                              Chairman of the Board

                                POWER OF ATTORNEY

      KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints Robert B. Grieve, Ronald L. Hendrick and
Michael A. Bent his or her attorney-in-fact, with the power of substitution, for
him or her in any and all capacities, to sign any amendment to this Registration
Statement on Form S-3, and to file the same, with exhibits thereto and other
documents in connection therewith, with the Securities and Exchange Commission,
granting to said attorney-in-fact full power and authority to do and perform
each and every act and thing requisite and necessary to be done in connection
therewith, as fully to all intents and purposes as he might or could do in
person, hereby ratifying and confirming all that said attorney-in-fact, or his
substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

      Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed below by the following persons on behalf
of the Registrant on January 7, 2002.



            SIGNATURE                              TITLE
-------------------------------   ---------------------------------------------
                               

/s/ Robert B. Grieve              Chief Executive Officer (Principal Executive
-------------------------------   Officer) and Chairman of the Board
Robert B. Grieve

/s/ Ronald L. Hendrick            Chief Financial Officer (Principal
-------------------------------   Financial and Accounting Officer)
Ronald L. Hendrick

/s/ William A. Aylesworth         Director
-------------------------------
William A. Aylesworth

/s/ A. Barr Dolan                 Director
-------------------------------
A. Barr Dolan

/s/ G. Irwin Gordon               Director
-------------------------------
G. Irwin Gordon




                                                                            II-4




            SIGNATURE                              TITLE
-------------------------------   ---------------------------------------------
                               

                                  Director
-------------------------------
Lyle A. Hohnke

                                  Director
-------------------------------
Edith W. Martin

/s/ John F. Sasen, Sr.            Director
-------------------------------
John F. Sasen, Sr.

/s/ Lynnor B. Stevenson
-------------------------------
Lynnor B. Stevenson               Director









                                                                            II-5

                                INDEX TO EXHIBITS



    EXHIBIT
    NUMBER    NOTES                             DESCRIPTION
    ------    -----   ----------------------------------------------------------
                
      5.1             Opinion of Wilson Sonsini Goodrich & Rosati, Professional
                      Corporation
     10.1             Share Purchase Agreement dated December 13, 2001
                      (incorporated by reference to the Current Report on Form
                      8-K filed by the Registrant on December 20, 2001)
     23.1             Consent of Wilson Sonsini Goodrich & Rosati, Professional
                      Corporation (included in Exhibit 5.1)
     23.2             Consent of Arthur Andersen LLP, independent accountants
     24.1             Power of Attorney (contained on Page II-4)








                                                                            II-6