Exhibit 10.23

               AMENDMENT TO CHANGE IN CONTROL SEVERANCE AGREEMENT


        This Amendment to Change in Control Severance Agreement ("Amendment"),
is made and entered into this the 1st day of October, 1998, by and between
Embrex, Inc. ("Company"), a North Carolina corporation, and Randall L. Marcuson
("Employee").

        WHEREAS the Company and Employee are parties to a Change in Control
Severance Agreement dated May 21, 1996, a copy of which is attached hereto as
Exhibit A (the "Severance Agreement") whereby the Company agrees to provide
Employee with certain payments and benefits in the event that Employee's
employment with the Company is terminated as a result of, or in connection with,
a Change in Control; and

        WHEREAS, the Company and Employee desire to amend the Severance
Agreement;
        NOW, THEREFORE, in consideration of the mutual agreements herein set
forth, the legal sufficiency and adequacy of which are hereby acknowledged, the
parties agree to amend the Severance Agreement as follows:

        1.      The Severance Agreement is amended by adding the following
paragraphs:
                16.  Covenant Not to Compete.  Employee  acknowledges that by
        virtue of his employment with the Company, he shall have access to and
        control of confidential and proprietary information concerning the
        Company's business and that the Company's business depends, to a
        considerable extent, on the individual's skills, efforts, and leadership
        of Employee. Accordingly, and in consideration of the Company's
        commitments to Employee under this Agreement, Employee expressly
        covenants and agrees that for the two (2) year period following the
        termination of his employment with the Company (regardless of
        circumstances of such termination) Employee will not, without the prior
        consent of the Company:




               (a) on Employee's own or another's behalf, whether as an officer,
               director, stockholder, partner, associate, owner, employee,
               consultant, or otherwise, directly or indirectly:
                      (i) within the geographical areas set forth below, solicit
                      or do business which is the same, similar to, or otherwise
                      in competition with the business engaged in by the Company
                      from or with persons or entities who are customers of the
                      Company, who were customers of the Company at any time
                      during the last year of Employee's employment with the
                      Company or to whom the Company had made proposals for
                      business at any time during the last year of Employee's
                      employment with the Company; or
                      (ii) offer employment to, or otherwise solicit for
                      employment, any employee or other person who had been
                      employed by the Company during the last year of
                      Employee's employment with the Company.
               (b) within the geographical area set forth below, be employed (or
               otherwise engaged) in a management capacity, other capacity
               providing the same or similar services which Employee provided to
               the Company, or any capacity connected with competitive business
               activities by any person or entity that engages in the same,
               similar, or otherwise competitive business as the Company;
        (c)    directly or indirectly take action which is primarily intended to
               be materially detrimental to the Company's goodwill, name,
               business relations, prospects, and operations.


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        (d)    the restrictions set forth in this Paragraph 16 apply to the
               following geographical areas:
               (i)   Research Triangle Park, North Carolina;
               (ii)  any city, metropolitan area, county (or similar political
                     subdivisions in foreign countries) in which the Company is
                     located, or does, or during Employee's employment with the
                     Company, did business;
               (iii) any city, metropolitan area, county (or similar political
                     subdivisions in foreign countries) in which Employee's
                     substantial services were provided, or for which Employee
                     had substantial responsibility, or in which Employee
                     performed substantial work on the Company's projects while
                     employed by the Company.
               Employee acknowledges that the covenants contained in this
        Paragraph 16 are reasonably necessary to protect the legitimate business
        interests of the Company and are reasonable with respect to scope, time,
        and territory and are described with sufficient accuracy and
        definiteness to enable him to understand the scope of the restrictions
        imposed upon him. If any of the provisions, clauses, or phrases in this
        Paragraph 16 are held unenforceable by a court of competent
        jurisdiction, then the parties desire that any such provision, clause or
        phrase be "blue-penciled" or rewritten by the court to the extent
        necessary to render it enforceable.

                 17. Income Tax Payment. In the event Employee receives payments
        or benefits pursuant to Paragraph 5 of this Agreement and incurs state
        or federal personal income tax liability as a result of the receipt of
        such payments or benefits, then Employee is entitled to receive an
        additional payment (the "Income Tax Payment") in an amount equal to the
        state and federal personal income tax



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        assessed on such payments or benefits. Said Income Tax Payment shall be
        made prior to any calculation of the Excise Tax Payment required by
        Paragraph 9 of this Agreement. Said Income Tax Payment shall be paid to
        Employee by the Company by April 15 of the year following each year in
        which such tax liability occurs.

          2. Except as herein set forth, the Severance Agreement is not modified
     or amended and the parties hereto reaffirm and agree to all of the terms
     and provisions of the Severance Agreement, as amended, in all other
     respects.

          IN WITNESS WHEREOF, the parties have executed this Amendment to Change
     in Control Severance Agreement as of the day and year first written above.

                                            EMBREX, INC.
                                                  /s/ Randall L. Marcuson
                                            By: ________________________________
                                                     President and CEO
                                            Title: _____________________________


ATTEST:

/s/ Don T. Seaquist
- ----------------------
Corporate Secretary

                                                       /s/ Randall L. Marcuson
                                                    ----------------------------
                                                          Randall L. Marcuson