Exhibit 3.1.3

                        CERTIFICATE OF AMENDMENT TO THE

                        CERTIFICATE OF INCORPORATION OF

                       BIO-REFERENCE LABORATORIES, INC.


To:   The Secretary of State
      State of New Jersey


      Pursuant to the provisions of Section 14A:7-2(2),  Corporations,  General,
of  the  New  Jersey  Statutes,   the  undersigned   corporation  executes  this
certificate of amendment to its certificate of incorporation:
      1.    The name of the corporation (hereinafter called the
"Corporation") is Bio-Reference Laboratories, Inc.
      2.  The  following  resolution  has  been  duly  adopted  by the  Board of
Directors of the  Corporation  as required by  Subsection  14A:7-2(3) of the New
Jersey Business Corporation Act.
      RESOLVED,  that pursuant to the authority vested in the Board of Directors
      of this  Corporation in accordance  with the provisions of its Certificate
      of Incorporation, the Board of Directors hereby creates a series of Series
      A Preferred Stock,  $.10 par value, of the Corporation,  and hereby states
      the  designation  and  amount  thereof  and  fixes  the  relative  rights,
      preferences  and  limitations  thereof (in addition to the  provisions set
      forth in the Certificate of Incorporation  of the  Corporation,  which are
      applicable to the  preferred  stock of all classes and series) as follows,
      so that ARTICLE (3) of the Corporation's  Certificate of Incorporation be,
      and it hereby is, amended by deleting the present  Article  (3)B(1) and by
      inserting  therein the following new paragraph B(1) immediately  following
      ARTICLE (3)(B), paragraph 7:

            "B(1).      Series A Senior Preferred Stock.
                        -------------------------------

            (a)   Designation and Amount.  An aggregate of
                  ----------------------
      604,078 shares of Series A Preferred Stock, $.10 par
      value, of the Corporation are hereby constituted as a

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      series  designated  as "Series A Senior  Preferred  Stock" (the  "Series A
      Senior  Preferred  Stock").  Such  number of shares  may be  increased  or
      decreased by resolution of the Board of Directors.


            (b)  Vote.  Except  as  may  otherwise  be  required  by  law,  this
      Certificate  of  Incorporation  or the  provisions  of the  resolution  or
      resolutions  as may be  adopted  by the  Board of  Directors  pursuant  to
      paragraph  (B) of this  Article  THIRD,  each  holder  of  Series A Senior
      Preferred  Stock  shall have one vote in respect of each share of Series A
      Senior  Preferred  Stock held by such holder on each matter  voted upon by
      the stockholders. The holders of shares of Series A Senior Preferred Stock
      and the holders of shares of Common Stock and any other  capital  stock of
      the  Corporation  having  general voting rights shall vote together as one
      class  on  all  matters  submitted  to  a  vote  of  stockholders  of  the
      Corporation.

            (c) Dividends.  Holders of Series A Senior  Preferred Stock shall be
      entitled to be paid dividends on a per share basis equal to dividends,  if
      any paid on a per share basis to holders of Common Stock, at the time such
      dividends are paid with respect to the Common Stock.

            (d)  Liquidation   Rights.   After   distribution  in  full  of  any
      preferential  amount (fixed in accordance with the provisions of paragraph
      (B) of this Article  THIRD),  if any, to be  distributed to the holders of
      Preferred  Stock in the event of  voluntary  or  involuntary  liquidation,
      distribution  or  sale  or  assets,  dissolution  or  winding-up  of  this
      Corporation,  the holders of the Series A Senior  Preferred Stock together
      with the holders of the Common  Stock shall be entitled to receive all the
      remaining assets of this Corporation, tangible and intangible, of whatever
      kind available for  distribution to  stockholders,  ratably on a per share
      basis  in  proportion  to the  number  of  shares  of the  Series A Senior
      Preferred Stock and the Common Stock held by each.

            (e) Conversion Rights. From and after the Date of Issuance and prior
      to the close of  business  on May 1,  2007,  each share of Series A Senior
      Preferred  Stock shall be convertible,  at the option of the holder,  upon
      payment  of the  Conversion  Price,  into one share of Common  Stock.  The
      initial  Conversion Price shall be $.75 per share. In the event of a stock
      dividend,  combination, stock split or reverse stock split, the Conversion
      Price and the number of shares of Common Stock into which the Series A

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      Senior Preferred Stock may be converted shall be appropriately adjusted."

      3. The foregoing  resolution was duly adopted by the Board of Directors of
the  Corporation  on May 17, 1997,  pursuant to authority  granted under Section
14A:7-2(2) of the New Jersey Business Corporation Act.
      4. The Certificate of  Incorporation of the Corporation is amended so that
the designation and number of shares of the series of Preferred Stock acted upon
in  the  foregoing  resolution,   and  the  relative  rights,   preferences  and
limitations of such series, are as stated in the resolution.
      IN WITNESS  WHEREOF,  Bio-Reference  Laboratories,  Inc.  has caused  this
Certificate of Amendment to the Certificate of Incorporation to be duly executed
this 25th day of March, 1998.

                                    BIO-REFERENCE LABORATORIES, INC.



                                 By /s/Marc D. Grodman
                                   -------------------
                                    Marc D. Grodman, President

ATTEST:



/s/Sam Singer
Sam Singer, Secretary

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