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                                                                 Exhibit 10(xlv)

                       SECOND AMENDMENT TO LOAN AGREEMENT

      THIS SECOND AMENDMENT TO LOAN AGREEMENT is made as of the 16th day of
March, 1998, by and between CORESTATES BANK, N.A. (the "Bank"), and CHRYSALIS
INTERNATIONAL CORPORATION, a Delaware Corporation, CHRYSALIS INTERNATIONAL
PRECLINICAL SERVICES CORPORATION, a Pennsylvania corporation, CHRYSALIS DNX
TRANSGENIC SCIENCES CORPORATION, an Ohio corporation and CHRYSALIS INTERNATIONAL
CLINICAL SERVICES CORPORATION, a Delaware corporation (each a "Borrower" and
together the "Borrowers").

                                   BACKGROUND

      A. The Bank and the Borrowers executed a Term Loan and Security Agreement
dated as of August 29, 1997, as amended by the First Amendment to Loan Agreement
dated September 24, 1997, (collectively, the "Loan Agreement"), pursuant to
which Bank made available to the Borrowers a credit facility in the maximum
principal amount of Five Million Dollars ($5,000,000) (the "Loan"). The Loan is
evidenced by a certain note dated August 29, 1997, executed and delivered by
Borrowers to Bank, in the original principal amount of the Loan (the "Note").
The Borrowers' obligations under the Loan Agreement and Note were and are
secured by a first priority lien on and security interest in the Collateral.

      B. The Borrowers have requested, and, subject to the terms and conditions
hereof, the Bank has agreed, to amend the Loan Agreement.

      NOW, THEREFORE, in consideration of the premises and covenants herein
contained and intending to be legally bound hereby, the parties agree as
follows:

                                      TERMS

      1. Defined Terms. Except as otherwise defined herein, words and terms
defined in the Loan Agreement shall have the same meanings when used herein.

      2. Amendments to Loan Agreement. The Loan Agreement is hereby amended as
follows:

            a. Section 6.10(h) of the Loan Agreement is hereby amended to read
as follows:

                  "(h) certain existing real estate of the Borrowers located in
Pennsylvania for which mortgages have been granted to the Pennsylvania
Industrial Development Authority and PNC Bank (the "PIDA and PNC Loans") and
liens or security interests created pursuant to a Note and Warrant Purchase
Agreement, dated the date hereof, by and between Chrysalis International
Corporation and PanLabs International, Inc. (the "PanLabs Loan"); and

            b. Section 6.11 of the Loan Agreement is hereby amended to read as
follows:

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                  "Indebtedness. Chrysalis and its subsidiaries will not incur
any Indebtedness in excess of an aggregate amount of $500,000, except for
amounts outstanding under the PIDA and PNC Loans, the PanLabs Loan, other
Indebtedness outstanding as of the Closing Date as identified on Schedule 5.1.3
and amounts available under credit facilities existing on the Closing Date."

      3. Representations and Warranties. In order to induce the Bank to enter
into this Second Amendment and amend the Loan Agreement as provided herein,
Borrowers hereby represent and warrant to the Bank that:

            (a) All of the representations and warranties set forth in the Loan
Agreement are true, complete and correct in all material respects on and as of
the date hereof with the same force and effect as if made on and as of the date
hereof and as if set forth in full herein.

            (b) No Event of Default under Sections 7.1.1 or 7.1.2 of the Loan
Agreement presently exists and is continuing on and as of the date hereof.

            (c) Since the date of the Borrowers' most recent financial
statements delivered to the Bank, no material adverse change has occurred in the
business, assets, liabilities, financial condition or results of operations of
Borrowers, and no event has occurred or failed to occur which has or will have
had a material adverse effect on the business, assets, liabilities, financial
condition or results of operations of Borrowers (excluding the delay in a
certain material contract which has been disclosed to the Bank, and for which
the Bank has received revised projections).

            (d) Borrowers have the full power and authority to execute, deliver
and perform any action or step which may be necessary to carry out the terms of
this Second Amendment and all other agreements, documents and instruments
executed and delivered by Borrowers to the Bank concurrently herewith or in
connection herewith (collectively, the "Amendment Documents"); each Amendment
Document has been duly authorized, executed and delivered by Borrowers and is
the legal, valid and binding obligation of Borrowers enforceable in accordance
with its terms, subject to any applicable bankruptcy, insolvency, general equity
principles or other similar laws affecting the enforcement of creditors' rights
generally.

            (e) The execution, delivery and performance of the Amendment
Documents will not (i) to the best of Borrowers' knowledge, violate any
provision of any existing law, statute, rule, regulation or ordinance which
violation may have a material adverse effect upon the business, financial
condition or results of operations of Borrowers, or (ii) conflict with, result
in a breach of or constitute a default under (x) the certificate of
incorporation or by-laws of Borrowers, (y) any order, judgment, award or decree
of any court, governmental authority, bureau or agency, or (z) any material
mortgage, indenture, lease, contract or other agreement or undertaking to which
Borrowers are a party or by which Borrowers or any of its properties or assets
may be bound.

      4. No Change. Except as expressly set forth herein, all of the terms and
provisions of the Loan Agreement shall continue in full force and effect.


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      IN WITNESS WHEREOF, the parties hereto, intending to be legally bound,
have caused this Agreement to be executed by their respective officers thereunto
duly authorized, as of the date first above written.

                                    CHRYSALIS INTERNATIONAL CORPORATION

                                    By: /s/ John G. Cooper
                                        ----------------------------------------
                                        Name: John G. Cooper
                                        Title: Sr. VP & CFO


                                    CHRYSALIS INTERNATIONAL PRECLINICAL
                                    SERVICES CORPORATION

                                    By: /s/ John G. Cooper
                                        ----------------------------------------
                                        Name: John G. Cooper
                                        Title: Vice President


                                    CHRYSALIS DNX TRANSGENIC SCIENCES
                                    CORPORATION

                                    By: /s/ John G. Cooper
                                        ----------------------------------------
                                        Name: John G. Cooper
                                        Title: Vice President


                                    CHRYSALIS INTERNATIONAL CLINICAL
                                    SERVICES CORPORATION

                                    By: /s/ John G. Cooper
                                        ----------------------------------------
                                        Name: John G. Cooper
                                        Title: Vice President


                                    CORESTATES BANK, N.A.

                                    By: /s/ Stephen McWilliams
                                        ----------------------------------------
                                        Name: Stephen McWilliams
                                        Title:  VP


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