<PAGE>

                                                                   EXHIBIT 10.25











Pages where confidential treatment has been requested are stamped "Confidential
Treatment Requested.  The redacted material has been separately filed with the
Commission."  The appropriate section has been marked at the appropriate place
with a star [*].


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<PAGE>

                                                                   EXHIBIT 10.25

                                   "Confidential Treatment Requested.  The
                                   redacted material has been separately filed
                                   with the Commission."

                                DISTRIBUTOR AGREEMENT


This agreement is entered into this 4th day of September, 1997 by and between
Alcide Corporation, a Delaware corporation whose offices are located at 8561
154th Ave. N.E., Redmond, Washington (hereinafter "Supplier") and
Ingenieursbureau lr. P.C. Heemskerk b.v. (hereinafter "Distributor").


NOW, THEREFORE, in consideration of the mutual covenants contained herein, the
parties agree as follows:

     1.   Definitions

          As used herein, the term
     
          1.1  "Contract Term" shall mean that period stated on Schedule A
attached hereto.

          1.2  "Product" shall mean Alcide-Registered Trademark- 4XLA-Registered
Trademark- Pre- and Post-Milking Teat Dip.  Product shall include any
refinements or improvements to 4XLA by Alcide Corporation during the term of
this Agreement.

          1.3  "Territory" shall be as defined by the attached Schedule B.

     2.   Appointment of Distributor

          2.1  Subject to the terms and conditions of this Agreement, Supplier
hereby appoints Distributor as non-exclusive distributor of the Product for the
Territory.  Distributor hereby accepts said appointment and agrees to actively
promote and sell the Product.

          2.2  In accepting this appointment, Distributor agrees that it and its
affiliates shall not, directly or indirectly, sell or distribute:

               (a)  Any other external udder care product/teat dip [*].

               (b)  Any product containing acidified chlorite as its active
ingredient [*].


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<PAGE>

          2.3  Distributor may appoint agents, dealers or sales representatives
to act on Distributor's behalf for sales of the Product in the Territory,
provided that any compensation to such agents, dealers or representatives shall
be solely Distributor's responsibility.

          2.4  Subject to the terms and conditions of this Agreement,
Distributor is authorized to sell the Product purchased from Supplier in such
manner, at such prices and upon such terms as Distributor shall determine. 
Distributor is an independent contractor, not an agent or representative of
Supplier.  Distributor shall not assume or create any obligation in the name of
Supplier or make any representation, warranty or guarantee on behalf of or in
the name of Supplier.

          2.5  Labeling of the Product shall be determined exclusively by
Supplier.

               In any of the Distributor's activities relating to the promotion
and sale of the Product, Supplier's name and trademark shall always be
prominently displayed in order to protect Supplier's rights and goodwill in the
same.  Whenever Supplier's name and trademark are used in advertising and
promotional programs, Supplier retains the right to review and approve same.  

          2.6  All registrations, trade names, trademarks and product names
under which the Product is sold shall be the property of Supplier.  In the event
any registrations (e.g., Product registrations) are taken or issued in the name
of Distributor, Distributor shall, upon request, but in no event later than upon
termination of this Agreement, transfer such registrations to Supplier or
Supplier's designee and provide any documents and assistance reasonably required
in connection therewith.

          2.7  This Agreement shall not be construed as establishing a
franchise.

          2.8  Supplier and Distributor each represent and warrant to the other
that it is authorized to enter into and perform this Agreement and that this
Agreement does not and shall not conflict with any other agreements it may have.

     3.   Terms and Conditions of Sale

          3.1  All of Distributor's orders for the Product shall be subject to
the terms and conditions set forth in this Section 3 and in the attached
Schedule D which provides product pricing and discounts; no additional or
different terms set forth in Distributor's or Supplier's purchase order,
acknowledgment or other forms or correspondence (other than an amendment to this
Agreement pursuant to Section 8.1 hereof) shall govern any sales of the Products
by Supplier to Distributor.


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<PAGE>

                                   "Confidential Treatment Requested.  The 
                                   redacted material has been separately filed
                                   with the Commission."

          3.2  Supplier shall be responsible for labeling, packing and shipping
all Product ordered in a form agreed upon between Supplier and Distributor as
being appropriate for the Territory and suitable for ready sale to the end user 
in the Territory.  All deliveries shall be [*].

          3.3  Supplier and Distributor have agreed to goal amounts of Product
(as set forth in Schedule A attached) to be purchased by Distributor during the
Contract Term.  Goals will be [*] so that appropriate marketing strategies can
be developed and implemented to facilitate attainment of the goal.  If goal
amounts are not established for any Contract Term, such goal amounts shall be
[*] than the goal amounts for the preceding Contract Term. [*]

          3.4  Distributor shall make payments to Supplier for Product ordered
by wire transfer within [*].

          3.5  Supplier provides the Limited Warranty as described in
Schedule C.

          3.6  Prices shown in Schedule D may be revised by Supplier at any time
during the Term of this Agreement  following sixty (60) days prior written
notice to Distributor from Supplier.

     4.   Promotional Activities

          4.1  Distributor shall undertake such advertising and promotional
activity relating to Product as is deemed appropriate by Distributor and
Supplier to actively promote sales.  Such advertising and promotional activity
shall be solely at Distributor's expense unless otherwise agreed to in writing
by Supplier.  All advertising and promotional materials developed by Distributor
shall be in accordance with descriptions of Product provided by Supplier and, to
the best of Distributor's knowledge, shall be accurate in all material respects.
Upon request, Supplier shall have the right to review and approve all
advertising and promotional materials developed by Distributor.

          4.2  [*]

          4.3  [*]  A list of major meetings, annual shows, seminars and
training programs at which Supplier's participation is desired shall be
submitted ninety (90) days in advance by Distributor.

          4.4  A tabulation of Distributor sales by Product and Territory shall
be provided by Distributor to Supplier at the end of each fiscal quarter. 
Distributor shall maintain records of sales to customers for a period of at
least two years and, upon request, provide Supplier with copies of such records.


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<PAGE>

                                   "Confidential Treatment Requested.  The 
                                   redacted material has been separately filed
                                   with the Commission."

     5.   Term and Termination

          5.1  Ninety (90) days prior to expiration of this Agreement,
Distributor and Supplier shall meet to discuss their intentions regarding a new
or extended agreement.

          5.2  This Agreement may be terminated by Supplier if Distributor fails
to purchase during the contract year at least [*].

          5.3  This Agreement may also be terminated by either party, effective
immediately upon notice to the other, in the event the party to which such
notice is sent becomes the subject of any bankruptcy or insolvency proceedings.

          5.4  This Agreement may be terminated by either party in the event
there is a material breach of this Agreement by the other party.  The injured
party shall give written notice of the breach.  The party in breach shall then
have 60 days to cure the breach.  If the breach is not cured within 60 days,
this Agreement shall be terminated.

          5.5  The provisions of Sections 2.2(b), 2.6, 4.4 and 7 and any accrued
obligations shall survive termination of this Agreement.

     6.   Applicable Law.

          This Agreement shall be governed by and construed in accordance with
the laws of the State of Washington, regardless of its or any other
jurisdiction's choice of law principles.  The 1980 U.N. Convention on Contracts
for the International Sale of Goods shall not apply to this Agreement. 
Distributor shall not make any claim or institute any litigation against
Supplier in connection with this Agreement or any invoice other than in the
courts of the State of Washington, U.S.A., King County, or the United States
District Court for the Western District of Washington.  Distributor hereby
irrevocably consents and submits to the jurisdiction of the courts of the State
of Washington and the United States District Court for the Western District of
Washington.

     7.   Confidential Information

          7.1  A.   Supplier and Distributor agree, with respect to any
confidential information received from the other and identified as confidential
information, that:

                    (a)  the receiving party shall use reasonable care to
prevent disclosure of the confidential information to any third party without
the prior written consent of the disclosing party, and the degree of care taken
by the receiving party shall be at least as great as the degree of care which
the receiving party takes in protecting its own confidential information; and


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<PAGE>

                    (b)  Receiving party shall not use confidential information
disclosed by the other party for any commercial purpose other than pursuant to
this Agreement, or publish or disclose it to third persons without the prior
written consent of the disclosing party.

               B.   Neither party shall have any obligation with respect to any
information disclosed by the other party:

                    (a)  which is already in the possession of the receiving
party at the time of its receipt from the disclosing party;

                    (b)  which the receiving party lawfully receives from
another person whose disclosure thereof to the receiving party does not violate
any rights of the disclosing party; or

                    (c)  which is or becomes published or otherwise publicly
available through no act or omission of the receiving party.

               C.   Upon expiration or termination of this Agreement,
Distributor and Supplier shall each, upon the written request of the other,
return or destroy all materials, copies thereof and extracts therefrom which
include any information designated as confidential by the other pursuant to
Section 7.1.A.  Each may, however, retain for legal archival purposes only, one
(1) copy of all such material.

               D.   The provisions of this Section 7.1 shall survive termination
of this Agreement and remain in full force and effect for a period of three (3)
years as to any item of confidential information.

     8.   Miscellaneous

          8.1  This Agreement constitutes the entire agreement between
Distributor and Supplier and may be amended only by a written document signed by
both parties hereto.

          8.2  All notices, requests or other communications under this
Agreement shall be given in the English language and will be deemed properly
given if in writing and delivered in person, sent via international courier
service or by confirmed facsimile transmission to the intended recipient at the
address specified below, or to such other address as a party may specify in
writing:


               If to Supplier:     Alcide Corporation
                                        Attn:  Joseph A. Sasenick


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<PAGE>

          If to Distributor:       Ingenieursbureau lr. P.C.
                                   Heemskerk b.v.
                                         Attn:  Eric N.A. Heemskerk

          8.3  The failure by either party to enforce any term or provision of
this Agreement shall not constitute a waiver of the same.

          8.4  This Agreement may be executed in any number of counterparts,
each of which shall be deemed an original and one and the same document.

          8.5  The rights of Distributor hereunder shall not be assigned or
transferred, either voluntarily or by operation of law, without the prior
written consent of Supplier, nor shall the duties of Distributor hereunder be
delegated in whole or in part.  Any such assignment, transfer or delegation
shall be of no force or effect.  Any change in control of Distributor shall be
deemed an impermissible assignment and entitle Supplier to terminate this
Agreement.  This Agreement shall be binding upon and inured to the benefit of
Supplier, its successors and assigns.

          8.6  If any provision of this Agreement is or becomes invalid, illegal
or unenforceable, the remaining provisions shall remain in full force and
effect, and for the invalid, illegal or unenforceable provision shall be
substituted a valid, legal and enforceable provision which shall be as similar
as possible in economic and business objectives as intended by the parties.

          8.7  Distributor shall comply with all applicable laws and regulations
in performing under this Agreement and reselling Product, including the U.S.
Foreign Corrupt Practices Act.

IN WITNESS WHEREOF, the parties have executed this Agreement on the date first
above written.


                                   ALCIDE CORPORATION
                                   ("Supplier")


                                   By: /s/ Joseph Sasenick
                                   Ingenieursbureau lr. P.C.
                                   Heemskerk b.v.
                                   ("Distributor")


                                   By /s/ Eric N.A. Heemskerk
                                   President


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<PAGE>

                                   "Confidential Treatment Requested.  The 
                                   redacted material has been separately filed
                                   with the Commission."


                                      SCHEDULE A

                                   (1) Contract Term
                                   (2) Goals

(1)  The Contract Term shall be a two year period commencing June 1, 1997, and
     ending May 31, 1999.

(2)  Goal amounts of Product to be purchased by Distributor from Supplier [*]
     after commencement of the Contract Term are as follows:

               Year 1  --     [*]
               Year 2  --     [*]





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                                      SCHEDULE B

                                      Territory





                                        France






                                          9
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                                      SCHEDULE C







                                   Limited Warranty

Alcide Corporation warrants to all purchasers of this Product that it has been
manufactured in accordance with U.S. regulatory requirements, is free of defects
and is as described in all labeling affixed hereto.  Alcide's sole obligation
under this warranty and buyer's sole remedy for any defect or failure to meet
such requirements or labeling shall be limited to replacement without cost
(except all costs for shipping and handling which shall be Distributor's
responsibility) of any quantity of the Product sold.

THE WARRANTY PROVIDED HEREIN AND THE OBLIGATIONS AND LIABILITIES OF ALCIDE
CORPORATION HEREUNDER ARE EXCLUSIVE AND IN LIEU OF, AND BUYER HEREBY WAIVES ALL
OTHER REMEDIES, WARRANTIES, GUARANTIES OR LIABILITIES, EXPRESS OR IMPLIED,
ARISING BY LAW OR OTHERWISE (INCLUDING, WITHOUT LIMITATION, ANY IMPLIED
WARRANTIES OF FITNESS FOR A PARTICULAR PURPOSE OR MERCHANTABILITY AND ANY
REMEDIES OR LIABILITIES FOR LOST PROFITS OR CONSEQUENTIAL DAMAGES).  BUYER
ACKNOWLEDGES THAT HE IS NOT RELYING ON THE JUDGMENT OF ALCIDE CORPORATION TO
SELECT OR FURNISH COMPONENTS OR MATERIALS SUITABLE FOR ANY PARTICULAR PURPOSE
AND THAT ALCIDE CORPORATION MAKES NO WARRANTIES OTHER THAN ON THE FACE HEREOF.



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<PAGE>

                                   "Confidential Treatment Requested.  The 
                                   redacted material has been separately filed
                                   with the Commission."





                                      SCHEDULE D


                                         [*]











Discount levels determined [*] based on [*].

                                   [*] Volume/Gallons

                              Discount Rate

                                   [*]


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