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                                                                   EXHIBIT 10.36

                              DOVER SADDLERY, INC.
                                 525 Great Road
                               Littleton, MA 01460

                                    Dated as of:  March 28, 2006


Bank of America, N.A.
  (successor by merger to Fleet National Bank)
100 Federal Street
Boston, Massachusetts  02110

      Re:   Second Amendment to Amended and Restated Loan Agreement

Ladies and Gentlemen:

      We refer to the Amended and Restated Loan Agreement, dated as of December
11, 2003 (as amended from time to time, the "Agreement"), between Dover
Saddlery, Inc. (the "Borrower") and Bank of America, N.A. (successor by merger
to Fleet National Bank) (the "Bank"). Upon the terms and subject to the
conditions contained in the Agreement, you agreed to make Revolving Loans to the
Borrower.

      Terms used in this letter of agreement (the "Second Amendment") which are
not defined herein, but which are defined in the Agreement, shall have the same
respective meanings herein as therein.

      We have requested that you make certain amendments to the Agreement. You
have advised us that you are prepared and would be pleased to make the
amendments so requested by us on the condition that we join with you in this
Second Amendment.

      Accordingly, in consideration of these premises, the promises, mutual
covenants and agreements contained in this Second Amendment, and fully intending
to be legally bound by this Second Amendment, we hereby agree with you as
follows:

                                    ARTICLE I

                             AMENDMENTS TO AGREEMENT

      Effective as of March 28, 2006, the Agreement is amended in each of the
following respects:

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      (a) The terms "Loan Documents" and "Security Documents" shall, wherever
used in any of the Loan Documents or Security Documents, be deemed to also mean
and include this Second Amendment.

      (b)   The following new sentence is added at the end of the definition
of "Total Debt Service":

                  It is agreed that there shall be excluded from the computation
            of Total Debt Service one-time, non-recurring interest expense, not
            to exceed $799,000 in the aggregate, which is directly related to
            non-cash accelerated deferred financing write-offs, including
            warrants, and prepayment fees in respect of the Patriot Subordinated
            Debt and private equity fees, and which are actually included in
            calculating Total Debt Service.

      (c) The table set forth in Section 5.19 of the Agreement is amended to
read in its entirety as follows:

<Table>
<Caption>
    PERIOD                           MINIMUM
    ------                           -------
<S>                                  <C>
    For the fiscal quarter ending    $3,700,000
    on March 31, 2006

    For the fiscal quarter ending    $3,300,000
    on June 30, 2006

    For the fiscal quarter ending    $3,200,000
    on September 30, 2006

    For the fiscal quarter ending    $4,300,000
    on December 31, 2006

    For any fiscal quarter ending    $5,500,000
    on or after March 31, 2007
</Table>

                                   ARTICLE II

                         REPRESENTATIONS AND WARRANTIES

      The Borrower hereby represents and warrants to you as follows:

      (a) Representations in Agreement. Each of the representations and
warranties made by the Borrower to you in the Agreement was true, correct and
complete when made and is true, correct and complete in all material respects on
and as of the date hereof with the same full force and effect as if each of such
representations and warranties had been made by the Borrower on the date hereof
and in this Second Amendment (except to the extent such representations and
warranties expressly relate to an earlier date).

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      (b) No Defaults or Events of Default. No Default or Event of Default
exists on the date of this Second Amendment (after giving effect to all of the
arrangements and transactions contemplated by this Second Amendment).

      (c) Binding Effect of Documents. This Second Amendment has been duly
executed and delivered to you by the Borrower and is in full force and effect as
of the date hereof, and the agreements and obligations of the Borrower contained
herein constitute the legal, valid and binding obligations of the Borrower
enforceable against the Borrower in accordance with their respective terms.

                                   ARTICLE III

                        PROVISIONS OF GENERAL APPLICATION

      (a) No Other Changes. Except to the extent specifically amended and
supplemented hereby, all of the terms, conditions and the provisions of the
Agreement and each of the Loan Documents and Security Documents shall remain
unmodified, and the Agreement and each of the other Loan Documents and Security
Documents, as amended and supplemented by this Second Amendment, are confirmed
as being in full force and effect.

      (b) Governing Law. This Second Amendment is intended to take effect as a
sealed instrument and shall be deemed to be a contract under the laws of the
Commonwealth of Massachusetts. This Second Amendment and the rights and
obligations of each of the parties hereto and thereto shall be governed by and
interpreted and determined in accordance with the laws of the Commonwealth of
Massachusetts.

      (c)   Binding Effect; Assignment.  This Second Amendment shall be
binding upon and inure to the benefit of each of the parties hereto and their
respective successors in title and assigns.

      (d) Counterparts. This Second Amendment may be executed in any number of
counterparts, each of which when executed and delivered shall be deemed an
original, but all of which together shall constitute one instrument. In making
proof of this Second Amendment, it shall not be necessary to produce or account
for more than one counterpart thereof signed by each of the parties hereto.

      (e) Conflict with Other Agreements. If any of the terms of this Second
Amendment shall conflict in any respect with any of the terms of any of the
Agreement or any other Loan Document, the terms of this Second Amendment shall
be controlling.

      (f)   Conditions Precedent.  This Second Amendment shall be effective
as of March 28, 2006, but only if:

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            (i) the form of acceptance at the end of this Second Amendment shall
be signed by the Borrower and the Lender, and the Consent at the end of this
Second Amendment shall be signed by the Guarantors;

            (ii) the Lender shall have received the amendment fee from the
Borrower in the amount of $16,000 (along with reimbursement of the Lender's
out-of-pocket expenses (including legal fees) in connection with the
transactions contemplated hereby); and

            (iii) the Lender shall have received originals or copies of the
modification of the Subordinated Debt Documents of even date, duly executed and
delivered by the parties thereto, and in form and substance satisfactory to the
Lender.

      If you are in agreement with the foregoing, please sign the form of
acceptance on the enclosed counterpart of this Second Amendment and return such
counterpart to the undersigned, whereupon this Second Amendment, as so accepted
by you, shall become a binding agreement between you and the undersigned.

                                    Very truly yours,

                                    The Borrower:

                                    DOVER SADDLERY, INC.



                                    By: /s/ Stephen L. Day
                                        Title: President

      The foregoing amendment is hereby accepted by the undersigned as of March
28, 2006.

The Bank:

BANK OF AMERICA, N.A.
  (successor by merger to Fleet National Bank)



By: /s/ Luanne T. Smith
    Title: Luanne T. Smith


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                              CONSENT OF GUARANTORS

      Each of DOVER SADDLERY, INC., a Delaware corporation and SMITH BROTHERS,
INC. (collectively, the "Guarantors") has guaranteed the Obligations of the
Borrower under (and as defined in) the Agreement. By executing this consent,
each Guarantor hereby absolutely and unconditionally reaffirms to the Bank that
such Guarantor's Guaranty remains in full force and effect. In addition, each
Guarantor hereby acknowledges and agrees to the terms and conditions of this
Second Amendment, and of the Agreement and the other Loan Documents as amended
hereby (including, without limitation, the making of the representations and
warranties and the performance of the covenants applicable to it herein or
therein).

                        DOVER SADDLERY, INC.



                        By: /s/ Stephen L. Day
                            Name: Stephen L. Day
                            Title: President

                        SMITH BROTHERS, INC.



                        By: /s/ Stephen L. Day
                            Name: Stephen L. Day
                            Title: President


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