UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                             ----------------------

                                  SCHEDULE 13D
                                 (RULE 13d-101)
                               (AMENDMENT No. 4)*

    INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULE 13d-1(A)
             AND AMENDMENTS THERETO FILED PURSUANT TO RULE 13d-2(A)

                             THE CATTLESALE COMPANY
                      (f/k/a Dynacore Holdings Corporation)
         --------------------------------------------------------------
                                (Name of Issuer)

                     COMMON STOCK, PAR VALUE $.01 PER SHARE
         --------------------------------------------------------------
                         (Title of Class of Securities)

                                   149479 10 7
                             (formerly 26779T 30 8)
         --------------------------------------------------------------
                                 (CUSIP Number)


                                  Tom F. Perles
                             Chief Financial Officer
                             AEI Environmental, Inc.
                               710 North York Road
                            Hinsdale, Illinois 60521
                             (630) 325-4232 ext. 222
 -------------------------------------------------------------------------------
   (Name, Address and Telephone Number of Person Authorized to Receive Notices
                               and Communications)

                                November 8, 2004
         --------------------------------------------------------------
             (Date of Event which Requires Filing of this Statement)

      If the filing person has previously filed a statement on Schedule 13G
   to report the acquisition that is the subject of this Schedule 13D, and is
 filing this schedule because of Rule 13d-1(e), 13(d)-1(f) or 13(d)- 1(g), check
                             the following box [ ].

     Note.  Schedules  filed in paper format shall include a signed original and
five copies of the schedule, including all exhibits. See Rule 13d-7(b) for other
parties to whom copies are to be sent.

     *The  remainder  of this cover  page  shall be filled  out for a  reporting
person's  initial  filing on this  form with  respect  to the  subject  class of
securities,  and for any subsequent amendment containing information which would
alter the disclosures provided in a prior cover page.

     The  information  required in the remainder of this cover page shall not be
deemed to be "filed"  for the purpose of Section 18 of the  Securities  Exchange
Act of 1934 ("Act") or otherwise  subject to the  liabilities of that section of
the Act but shall be subject to all other  provisions of the Act  (however,  see
the Notes).




------------------------
CUSIP NO. 149479 10 7
------------------------

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1.       NAME OF REPORTING PERSONS

         AEI ENVIRONMENTAL, INC.

         S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS
         (Intentionally Omitted)
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2.       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

                                                              (A) [   ]
                                                              (B) [   ]
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3.       SEC USE ONLY

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4.       SOURCE OF FUNDS

                  NOT APPLICABLE
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5.       CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
         ITEMS 2(d) OR 2(e)

                                                              [x]
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6.       CITIZENSHIP OR PLACE OF ORGANIZATION

         COLORADO
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         NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH

7.       SOLE VOTING POWER                                    5,061,066

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8.       SHARED VOTING POWER                                  0

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9.       SOLE DISPOSITIVE POWER                               5,061,066

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10.      SHARED DISPOSITIVE POWER                             0

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11.      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

                                                              5,061,066
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12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES.
                                                              [   ]
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13.      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11).

         11.4%
--------------------------------------------------------------------------------
14.      TYPE OF REPORTING PERSON.

         CO
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      STATEMENT ON SCHEDULE 13D PURSUANT TO RULE 13D-1 UNDER THE SECURITIES
                        EXCHANGE ACT OF 1934, AS AMENDED

ITEM 1. SECURITY AND ISSUER.

     This amended  Statement on Schedule 13D (this  "Statement")  relates to the
beneficial  ownership  of common  stock,  par value $0.01 per share (the "Common
Stock") of The  CattleSale  Company (f/k/a  Dynacore  Holdings  Corporation),  a
Delaware  corporation (the "Company").  The principal  executive  offices of the
Company are located at 9901 IH-10 West, Suite 800, San Antonio, Texas 78230.

ITEM 2. IDENTITY AND BACKGROUND.

         Item 2 of the Schedule 13D is hereby supplemented as follows:

     (a) - (f) This  Statement  is being  filed by AEI  Environmental,  Inc.,  a
Colorado corporation (the "Reporting Person").  There is no change to report for
Item 2 as of the date of this Amendment No. 4.


ITEM 3. SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION.

         Not applicable.

 
ITEM 4. PURPOSE OF TRANSACTION.

         (a)      The response to Item 6 is incorporated by reference.

         (b)-(c)  Not applicable.

         (d)      Item 4(d) of the Schedule 13D is supplemented as follows:

     Based on information publicly disseminated by the Company as of the date of
this Statement,  the Reporting  Person is not aware of any change in the present
board of directors or management of the issuer, including any plans or proposals
to change the number or term of directors  or to fill any existing  vacancies on
the board.

         (e)      Item 4(e) of the Schedule 13D is supplemented as follows:

     Based on information publicly disseminated by the Company as of the date of
this  Statement,  the  Reporting  Person  is  not  aware  of any  change  in the
capitalization or dividend policy of the issuer.


         (f)      Item 4(f) of the Schedule 13D is supplemented as follows:

     Based on information publicly disseminated by the Company as of the date of
this Statement,  the Reporting Person is not aware of any other material changes
in the issuer's business or corporate structure.

         (g)-(j)  Not applicable.

 
ITEM 5. INTEREST IN SECURITIES OF THE ISSUER.
 
     There is no change  to report  for Item 5 except  for the  addition  of the
following:

     (a) The Reporting  Person is the beneficial owner of 5,061,066  shares,  or
11.4%, of the Company's outstanding Common Stock (on a fully converted basis) as
of the date of this Statement (based upon 44,391,094  shares of Common Stock [on
a fully  converted  basis]  outstanding as of September 30, 2004, as reported in
the issuer's  Quarterly  Report on Form 10-Q for the quarter ended September 30,
2004). See Item 5(c) regarding the number of shares and percentage ownership for
other persons  required to be disclosed in response to Item 2 and  Instruction C
to Schedule 13D.

     (b) See Item 5(c)  regarding the number of shares as to which there is sole
power to vote or direct  the vote,  shared  power to vote or to direct the vote,
sole power to dispose or to direct the disposition or shared power to dispose or
to direct the  disposition  for persons  required to be disclosed in response to
Item 2 and Instruction C to Schedule 13D.

     (c) The  Reporting  Person has not effected any  transaction  in the Common
Stock of the Company during the past 60 days, except for the following:

     Between  February  11, 2004 and  November  8, 2004,  the  Reporting  Person
disposed of in private  transactions  a total of 74,541  shares of the Company's
Series B Preferred Stock and 889,192 shares of the Company's  Common Stock,  all
of which shares were originally acquired in the transaction previously disclosed
in Item 3. The  aforementioned  Series B  Preferred  Stock is  convertible  into
540,422 shares of the Company's Common Stock. All of the  aforementioned  shares
of Series B  Preferred  Stock and Common  Stock were  distributed  either to (i)
holders of the Reporting Person's Senior Secured  Convertible  Promissory Notes,
(ii)  holders  of other  debt upon the  respective  note  holder's  election  to
exercise to convert the debt,  (iii) to  creditors  of the  Reporting  Person in
settlement  of  the  respective  liabilities,  or  (iv),  to  a  lesser  extent,
represented  contracted  amounts or grants  approved by the  Reporting  Person's
board of directors for services rendered to the Reporting Person. Following is a
summary of those  individuals and  organizations who received in excess of 1% of
the Company's  outstanding Common Stock, on a fully converted basis,  during the
aforementioned  period from February 11, 2004 to November 8, 2004,  and from the
date of the  transaction  previously  disclosed in Item 3 (February 25, 2003) to
November 8, 2004:





                                                              Period 2/11/04 to 11/8/04    Period 2/25/03 to 11/8/04
                                                                             Percent of                   Percent of
                                                              Common           Total        Common            Total
                                                               Stock        Outstanding      Stock         Outstanding
                                                                                            

MPI Venture Management. LLC (*, -)                           1,000,011        2.25%        3,203,688         7.22%
Horace H. Work                                                     -            -          1,546,446         3.48
Thomas F. Taft, Sr.                                                -            -          1,221,860         2.75
Douglas A. Dyer (**)                                               -            -          1,093,221         2.46
John T. Zick                                                       -            -            676,907         1.52
William J. Ritger                                                  -            -            646,676         1.46
Tom F. Perles     (***)                                        270,000        0.61           600,000         1.36
Bruce A. Brown                                                     -             -           575,548         1.30
Broadstreet Investment
  Management, LLC (****)                                           -             -           498,732         1.12
Others   (individually less than 1%)(+)                        159,603        0.36         4,060,775         9.15
                                                             _________        _____       __________        ______   
                                                             1,429,614        3.22%       14,123,853        31.82%
                                                             =========        =====       ==========        ======



     -,+  Excludes  (-) / includes  (+) 50,000  shares of Common  Stock that MPI
Venture Management, LLC directed be issued to a third party on its behalf.

     * Messrs.  David W. Pequet and Mark A. Margason each own 50% of MPI Venture
Management, LLC, and both are directors of the Company and the Reporting Person.
Messrs.  Pequet and Margason have shared power to vote or to direct the vote and
shared power to dispose or to direct the  disposition of the shares  reported as
beneficially owned.

     ** Includes  575,045  shares owned in joint  tenancy with James H. Brennan.
Mr. Dyer is a director of the Reporting  Person.  Messrs.  Brennan and Dyer have
shared  power to vote or to direct  the vote and  shared  power to dispose or to
direct the disposition of the jointly-owned shares.

     ***  Mr.  Perles  is the  president  and  chief  financial  officer  of the
Reporting  Person and was a director of the Reporting  Person from July 10, 2003
to June16, 2004.

     **** Broadstreet Investment  Management,  LLC is a venture fund, managed by
Messrs.  Douglas A. Dyer and James H.  Brennan.  Messrs.  Brennan  and Dyer have
shared  power to vote or to direct  the vote and  shared  power to dispose or to
direct the disposition of the shares.
        
     After giving  effect to these  transactions,  the  Reporting  Person is the
beneficial owner of 5,061,066 shares, or 11.4%, of the outstanding Common Stock.

         (d) - (e) Not applicable.

 
 
     ITEM 6.  CONTRACTS,  ARRANGEMENTS,  UNDERSTANDINGS  OR  RELATIONSHIPS  WITH
RESPECT TO SECURITIES OF THE ISSUER.

         Item 6 of the Schedule 13D is supplemented as follows:
 
     The  shareholders  of the  Reporting  Person and the  holders of the Senior
Secured  Convertible  Promissory  Notes of the Reporting Person (the "Promissory
Notes") have approved a Plan of  Reorganization of the Reporting Person pursuant
to which all of the Series B Preferred  Stock and Common  Stock  acquired in the
transaction  previously  disclosed  in  Item 3 will  be (i)  distributed  to the
holders of the  Promissory  Notes and other  creditors of the Reporting  Person,
(ii) sold in private  transactions  to raise  working  capital  to  sustain  the
Reporting Person's operations during a "wind-down" period, and (iii) any balance
will be  distributed  on a pro rata basis to the  shareholders  of the Reporting
Person.

     Other  than  as  described  in  this  Statement,  to the  knowledge  of the
Reporting  Person,  there  are no  contracts,  arrangements,  understandings  or
relationships (legal or otherwise) among the persons named in Item 2 and between
such  person  and any person  with  respect to any  securities  of the  Company,
including,  but not limited to, transfers or voting of any securities,  finder's
fees, joint ventures, loan or option arrangements,  puts or calls, guarantees of
profits, division of profits or loss, or the giving or withholding of proxies.


ITEM 7. MATERIAL TO BE FILED AS EXHIBITS.

Exhibit           Description
-------           -----------

                  None
 

                                    SIGNATURE

     After  reasonable  inquiry  and to the best  knowledge  and  belief  of the
undersigned,  the information set forth in this statement is true,  complete and
correct.

Dated: January 28, 2005


                                       AEI ENVIRONMENTAL, INC.
 

                                       By:  /s/   Tom F. Perles
                                     ------------------------------------------
                                                 Tom F. Perles
                                             President, Chief Financial Officer
                                                 and Secretary




                                   APPENDIX A

     Executive Officers and Directors of AEI Environmental, Inc.
     -----------------------------------------------------------

     Unless otherwise  indicated below,  each director and executive  officer of
the Reporting  Person is a U.S.  citizen and has his or her business address c/o
AEI Environmental, Inc., 710 North York Road, Hinsdale, Illinois 60521.

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NAME                                        PRINCIPAL OCCUPATION OR EMPLOYMENT
--------------------------------------------------------------------------------
David W. Pequet, Director              President,  MPI Investment Management,  
                                       Inc., 710 North York Road, 
                                       Hinsdale, Illinois 60521.
--------------------------------------------------------------------------------
Mark  A.  Margason,   Director         Chief  Financial  Officer,  
                                       MPI  Investment Management, Inc.,
                                       710 North York Road, 
                                       Hinsdale, Illinois 60521.
--------------------------------------------------------------------------------
Edward L. McMillan,  Chairman          President and CEO, McMillan L.L.C., 
                                       105 North 3rd Street, Suite 204, 
                                       Greenville, Illinois 62246
--------------------------------------------------------------------------------
Douglas  Dyer,  Director               Partner,  Brennan Dyer & Company,  LLC, 
                                       735 Broad Street, Suite 218, 
                                       Chattanooga, Tennessee 37402
--------------------------------------------------------------------------------

Tom F. Perles,  President,             AEI  Environmental,  Inc., 
Chief Financial Officer                710 North York Road,
and Secretary                          Hinsdale,  Illinois 60521