<PAGE>


DISTRIBUTOR AGREEMENT                                              EXHIBIT 10.20



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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DISTRIBUTOR AGREEMENT                                       EXHIBIT 10.20

This Distributor Agreement (the "Agreement") is made this 30th day of October,
1996, by and between Alcide Corporation ("Alcide"), a Delaware corporation whose
offices are located in Redmond, Washington, and ABS Global, Inc. ("ABS"), a
Delaware corporation whose offices are located in DeForest, Wisconsin.

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 referenced in Schedule A
attached hereto, which Schedule may be revised annually during the term of this
Agreement pursuant to Section 5.1.

         1.2  "Product" shall refer to Alcide external teat dip products.

         1.3  "Territory" shall mean the United States of America.

    2.   APPOINTMENT AND AUTHORITY OF ABS

         2.1  Subject to the terms and conditions of this Agreement, Alcide
hereby appoints ABS as the exclusive distributor of the Product for the markets
listed in Schedule B (the "Exclusive Markets") and as non-exclusive distributor
of the Product for the balance of the markets (the "Non-Exclusive Markets") in
the Territory.  Regarding the Exclusive Markets, Alcide shall not license or
appoint any other person, corporation or other entity, or authorize any other
person, corporation or other entity to act as a distributor for the Product.
Additionally, Alcide shall not deliver Product to another distributor's facility
located in the Exclusive Markets.  Regarding the Non-Exclusive Markets, Alcide
shall not sell the Product to members of the ABS representative organization in
the United States, or to competitive semen organizations or to milk cooperatives
in the Territories.  ABS hereby accepts said appointments and agrees to actively
promote and sell the Product in the Territory.  ABS shall not sell a competing
teat dip product in the Territory during the term of this Agreement.  The
parties acknowledge that ABS is marketing a pre-moistened towel product which
shall not be considered a breach of this Agreement.

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


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         2.3  Subject to the terms and conditions of this Agreement, ABS is
authorized to sell the Product in such manner, at such prices and upon such
terms as ABS shall determine.  ABS is an independent contractor, not an agent or
employee of Alcide.  ABS may continue to supply accessories (cups, pumps, etc.)
relating to the Product.

         2.4  A.   Labeling of the Product shall be as mutually determined by
Alcide and ABS but shall include a notice of distribution by ABS including ABS's
trade names and trademark.  Any changes to Product labels shall be mutually
agreed upon by Alcide and ABS.  ABS agrees to reimburse Alcide for the design,
plates and printing costs of any labels changed and/or remaining at the
termination of this Agreement.

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

         2.5  All trade names, trademarks and product names (the "Intellectual
Property"), excluding the ABS and American Breeders Service trademarks, under
which Product is sold shall be the property of Alcide.

         2.6  A.   If Alcide shall develop additional external teat dip
products, Alcide shall give ABS the right of first refusal to market these
Products in the Territory covered by this Agreement on the same basis of
exclusive or non-exclusive markets.

              B.   If Alcide shall develop and distribute additional bovine
health products through distributors other than ABS, Alcide shall not establish
trade name(s) for such product(s) or promotional and/or advertising programs
with respect to such product(s) which could be reasonably construed by the end
user as associating such product(s) with ABS.

         2.7  If this Agreement is terminated prior to its scheduled termination
date, ABS will not introduce or market a product formulated with technology
covered by Alcide patents or products sold by ABS under this Agreement, provided
however, in such event, ABS will be permitted to distribute a competitive line
of uddercare products.

    3.   TERMS AND CONDITIONS OF SALES

         3.1  All of ABS's orders for the Product shall be subject to the terms
and conditions set forth in this Section 3; no additional or different terms set
forth in ABS's or Alcide's purchase order, acknowledgment or other forms or
correspondence (other than an amendment to this Agreement pursuant to
Section 7.1 hereof) shall govern any sales of the Product by Alcide to ABS.


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                                               CONFIDENTIAL TREATMENT REQUESTED.
                                       THE REDACTED MATERIAL HAS BEEN SEPARATELY
                                                      FILED WITH THE COMMISSION.

         3.2  Alcide and ABS will make a good faith effort to agree upon goal
amounts of Product  to be purchased from Alcide by ABS for the Territory during
this Contract (Schedule A).  Goals will be reviewed quarterly so appropriate
marketing strategies can be developed and implemented to facilitate attainment
of goals.  ABS has provided a [*] forecast of anticipated Product purchases [*]
which will be used solely to facilitate Alcide's planning.  [*] purchase orders
will be issued to Alcide by ABS [*].  Alcide shall provide the Product in a
timely manner and in the amounts requested.

         3.3  Alcide shall be responsible for appropriately packaging all
Product in packages suitable for use by ABS's customers.  All shipments shall be
F.O.B. Manufacturing Plant location.  Shipping costs shall be at ABS's expense
and ABS shall be responsible for arranging transportation.  Alcide shall make a
good faith effort to accommodate unscheduled orders.  In addition, with each
unit of Product, Alcide shall provide, at Alcide's sole expense, with respect to
the Products covered by that shipment:

             (i)   all necessary or appropriate instructions as to proper use of
                   Product;

            (ii)   warnings on product limitations/safety as deemed appropriate;
                   and

           (iii)   limited warranty statements in the form attached hereto as
                   Schedule C.

         3.4  Alcide provides the limited warranty described in Schedule C and
warrants that Product delivered to ABS will be manufactured under Good
Manufacturing Practices standards as defined by the U.S. Food and Drug
Administration and will be free from defects.  Alcide's sole obligation under
this warranty shall be limited to replacement without cost (except all costs for
shipping and handling) of any quantity of the Product sold.  Alcide also
warrants that Alcide is authorized to enter into this Agreement and to grant ABS
the distribution rights provided for in Section 2.1.  ABS warrants that all
advertising and promotional material developed by ABS will be in accordance with
the descriptions of Product provided by Alcide and to the best of ABS's
knowledge will be accurate in all material respects.  ABS warrants that ABS is
authorized to enter into this Agreement and this Agreement does not and will not
infringe upon any other agreements it may have.

         3.5  The agreed upon purchase prices for Products for the Contract Term
shall be specified in Schedule D and may only be revised by Alcide with sixty
(60) days prior written notice to ABS.

         3.6  Provided that the Product has been distributed by ABS in
accordance with this Agreement, Alcide shall indemnify ABS and ABS's officers,
directors, employees, agents, dealers



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                                               CONFIDENTIAL TREATMENT REQUESTED.
                                       THE REDACTED MATERIAL HAS BEEN SEPARATELY
                                                      FILED WITH THE COMMISSION.

and sales representatives against any claims which may arise due to Product
defects or defects in instruction and warnings as provided by Alcide or which
may arise due to any other breach by

Alcide of its warranties set forth in Sections 3.3 and 3.4 hereof and attached
Schedule C.  ABS agrees to indemnify Alcide against any claims which may arise
due to ABS, its officers, directors or employees advising the use of the Product
in a manner inconsistent with the stated instructions and warnings on the
Product label.  Alcide and ABS shall give prompt notice to the other of any
claim, threatened claim or litigation which in any way relates to the Product
distributed under this Agreement.  Alcide and ABS shall provide reasonable
cooperation and assistance to each other in the defense of any claim or
litigation relating to the use of Product distributed under this Agreement.

         3.7  Payment terms shall be [*].  ABS agrees and understands that
interest shall be charged [*].

     4.  PROMOTIONAL ACTIVITIES; MARKETING

         4.1  Alcide shall regularly advise ABS of any new developments
concerning Product availability and formulation.

         4.2  ABS will undertake such advertising and promotional activity
relating to Product as is deemed appropriate by ABS.  Alcide may participate
with ABS and other distributors in jointly sponsored promotional programs and
continue to sponsor with ABS the annual Presidents Club meetings.  ABS will be
responsible for whatever operational expenses it incurs in connection with the
sale and distribution of the Product.

         4.3  The parties acknowledge that in the non-exclusive territories high
performing reps should be incentivised to maintain and improve their share of
market.  Such incentives, while not specifically defined in this Agreement, may
include programs sponsored individually or jointly by the parties.  For any such
incentive program, payment shall be made quarterly for the preceding quarter's
performance.

         4.4  Alcide shall have the right to use all promotional material for
which it has partially reimbursed ABS, provided ABS approves such use in
writing.  Such approval will not be unreasonably withheld.

         4.5  ABS's marketing plans for Product shall be provided to Alcide [*].
A list of meetings, seminars and training programs at which Alcide's
participation is desired will be submitted ninety (90) days in advance by ABS.


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<PAGE>


         4.6  A tabulation of ABS's sales by Products shall be provided by ABS
to Alcide at the end of each calendar quarter.

         4.7  Thirty days after each ABS fiscal quarter ABS will meet with
Alcide to discuss (i) sales performance by business unit, which is summarized by
strategic business unit and market/Territory; (ii) promotional and marketing
activity and the results of the activity; and (iii) appraisal of competitive
activity, new products, etc.

     5.  TERM AND TERMINATION

         5.1  This Agreement may be extended upon the mutual agreement of both
parties.

         5.2  Either party may terminate this Agreement at any time in the case
of a material breach of this Agreement by the other party; provided that written
notice, specifying the alleged breach in reasonable detail, shall have been
given to the party breaching this Agreement not less than ninety (90) days prior
to the effective date of such termination and provided further than the party to
which such notice is sent shall have failed to cure such breach within thirty
(30) days following such notice.  Upon termination of this Agreement, ABS shall
sell its inventory of Alcide's Product on the open market or otherwise dispose
of the Product.

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

     6.  CONFIDENTIALITY

         6.1  Confidential Information

              Alcide and ABS agree, with respect to any confidential information
received from the other and identified as confidential information that:

              A.   This Section 6.1, Confidential Information, including all
subsections, supersedes all previous agreements between ABS and Alcide, in
writing or otherwise, with regard to confidential information, except that
confidential information disclosed and properly identified as such pursuant to
the previous agreements between the parties shall remain subject to the
confidentiality obligation provided for therein.

              B.   With respect to the disclosure of information by either party
to the other pursuant to this Agreement, the disclosure of any portion of such
information which the disclosing party regards as confidential information will
be made subject to the following conditions:


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                   (a)  The information must be in writing or in drawing or on
some other permanent record and must be clearly marked or identified as being
confidential information and must identify such confidential information as
being:

                   (i)  marketing;
                  (ii)  technological;
                 (iii)  chemical.

                   (b)  If confidential information is verbally disclosed, as
may happen during meetings of representatives of the parties, then, within ten
(10) working days after such disclosure, the disclosing party will deliver to
the other party a letter specifically identifying the confidential information
so disclosed and indicating that the information is to be treated as
confidential information.

         Neither party shall have any obligation to the other with respect to
information disclosed but not identified as confidential information pursuant to
this Section 6.1.B.

         C.   With respect to any confidential information received from the
other and identified as confidential information pursuant to Section 6.1.B:

              (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

              (b)  the receiving party will 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.

         D.   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.

         E.   ABS's obligation to consider as confidential information disclosed
by Alcide for which ABS has been granted rights under this Agreement shall not
prevent ABS from using such information to carry out the purposes and intent of
this Agreement.


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<PAGE>


         F.   Upon termination of this Agreement, ABS and Alcide shall each,
upon the written request of the other, return or destroy all material, copies
thereof and extracts therefrom which include any information designated as
confidential by the other pursuant to Section 6.1.B.  Each may, however, retain,
for legal archival purposes only, one copy of all such material.

         G.   The provisions of this Section 6.1 shall survive termination of
this Agreement and remain in full force and effect as to any item of
confidential information for:

              (a)  three (3) years if such item of confidential information is
                   marketing information;

              (b)  five (5) years if such item of confidential information is
                   technological information; or

              (c)  ten (10) years if such item of confidential information is
                   chemical information.

     7.  MISCELLANEOUS

         7.1  This Agreement constitutes the entire agreement between ABS and
Alcide relating to the Territory, superseding all previous agreements and may be
amended only by a written document signed by both parties hereto.

         7.2  All notices, elections, demands or other communications required
or permitted to be made or given pursuant to this Agreement shall be in writing
and shall be considered as properly given or made if sent by pre-paid first-
class mail, overnight courier or delivery service, or if transmitted by any
telecommunication device (e.g., telex or telecopier) and addressed or sent to
the respective parties' addresses specified below.  Either party may change its
address by giving prior written notice to the other party of its new address.


         If to Alcide:                 Alcide Corporation
                                       8561 154th Avenue, N.E.
                                       Redmond, Washington  98052
                                       Attn:  Joseph A. Sasenick
         with a copy to:               James R. Lisbakken
                                       Perkins Coie
                                       1201 Third Avenue
                                       Seattle, Washington  98101
         If to ABS:                    ABS Global, Inc.
                                       6908 River Rd., P.O. Box 459
                                       DeForest, Wisconsin  53532
                                       Attn:  President


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<PAGE>


         with a copy to:               Peter C. Langenus, Esquire
                                       General Counsel
                                       Schnader, Harrison, Segal & Lewis
                                       330 Madison Avenue
                                       New York, New York  10017

         7.3  Applicable Law.  This Agreement shall be construed in accordance
with the laws of the State of Delaware except that, as to those matters, if any,
as to which law would be superseded by the federal law of the United States of
America, that law shall control.


         IN WITNESS HEREOF, the parties have executed this Agreement on the date
first above written.
                                       Alcide Corporation

                                       By:s/
                                          ------------------------------------
                                       John P. Richards
                                       Executive Vice President
                                       Hereunto Duly Authorized

                                       ABS Global, Inc.

                                       By:s/
                                          ------------------------------------
                                       Dennis McCormick
                                       President, CEO
                                       Hereunto Duly Authorized


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                                               CONFIDENTIAL TREATMENT REQUESTED.
                                       THE REDACTED MATERIAL HAS BEEN SEPARATELY
                                                      FILED WITH THE COMMISSION.

                                   SCHEDULE A

    Contract term shall mean the two-year period commencing November 1, 1996 and
running through and including October 31, 1998.

    Goal amounts of product purchased from Alcide by ABS for each contract year
in gallons is [*] for all territories, both domestic and international.


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                                               CONFIDENTIAL TREATMENT REQUESTED.
                                       THE REDACTED MATERIAL HAS BEEN SEPARATELY
                                                      FILED WITH THE COMMISSION.

                                   SCHEDULE B

    EXCLUSIVE MARKETS

         ABS Business Units

                [*]















         *    ABS's right to an exclusive market is dependent on [*].

         **   ABS's right to an exclusive market is dependent on [*].



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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 shall be limited to replacement without cost
(except all costs for shipping and handling) of any quantity of the Product
sold.

THE WARRANTY PROVIDED HEREIN AND THE OBLIGATIONS AND LIABILITIES OF ALCIDE
CORPORATION THEREUNDER ARE EXCLUSIVE AND IN LIEU OF, AND BUYER HEREBY WAIVES ALL
OTHER REMEDIES, WARRANTIES, GUARANTEES OR LIABILITIES, EXPRESS OR IMPLIED,
ARISING BY LAW OR OTHERWISE (INCLUDING WITHOUT LIMITATION ANY OBLIGATIONS OF
ALCIDE CORPORATION WITH RESPECT TO FITNESS, MERCHANTABILITY AND CONSEQUENTIAL
DAMAGES).  THE 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 THERE ARE NO WARRANTIES WHICH EXTEND BEYOND THE
DESCRIPTION ON THE FACE HEREOF.


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                                               CONFIDENTIAL TREATMENT REQUESTED.
                                       THE REDACTED MATERIAL HAS BEEN SEPARATELY
                                                      FILED WITH THE COMMISSION.

                                   SCHEDULE D

    Commencing [*] Product will be discounted as follows depending on the
quarterly amount of Product that ABS purchases whether for sale within or
outside the United States and whether pursuant to this Agreement or any other
agreement relating to Product:

    [*]






    Discounts levels determined quarterly based on [*].


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