<PAGE>   1
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                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549


                                    FORM 10-Q/A


[x]             QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d)
                     OF THE SECURITIES EXCHANGE ACT OF 1934
                  For the quarterly period ended March 31, 1998

                                       OR

[ ]             TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d)
                     OF THE SECURITIES EXCHANGE ACT OF 1934
             For the transition period from __________ to _________


                         COMMISSION FILE NUMBER 0-27818



                             DOANE PRODUCTS COMPANY
             (Exact name of Registrant as specified in its charter)



                 DELAWARE                                    43-1350515
      (State or other jurisdiction                        (I.R.S. Employer
    of incorporation or organization)                    Identification No.)


          WEST 20TH STREET AND
            STATE LINE ROAD
            JOPLIN, MISSOURI                                     64804
(Address of principal executive offices)                       (Zip Code)


                                 (417) 624-6166
              (Registrant's telephone number, including area code)


     Indicate by check mark whether the Registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
Registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days. Yes [x] No [ ]

     As of May 1, 1998, the Registrant had outstanding 1,000 shares of Common
Stock.

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<PAGE>   2

                                TABLE OF CONTENTS

                                     PART I
                              FINANCIAL INFORMATION

<TABLE>
<CAPTION>
                                                                                                           PAGE

<S>               <C>                                                                                      <C>
Item 1.           Financial Statements.......................................................................1

                  Consolidated Balance Sheets- March 31, 1998 and December 31, 1997..........................1

                  Consolidated Statements of Income- three months ended
                  March 31, 1998 and March 31, 1997..........................................................2

                  Consolidated Statements of Cash Flow- three months ended
                  March 31, 1998 and March 31, 1997..........................................................3

                  Notes to Consolidated Financial Statements.................................................4


Item 2.           Management's Discussion and Analysis of Financial Condition
                  and Results of Operations..................................................................6


Item 6.           Exhibits and Reports on Form 8-K

                                                       PART II

                                                  OTHER INFORMATION



Signatures...................................................................................................9
</TABLE>




                                       (i)
<PAGE>   3

                      DOANE PRODUCTS COMPANY AND SUBSIDIARY

                           CONSOLIDATED BALANCE SHEETS
                             (DOLLARS IN THOUSANDS)

<TABLE>
<CAPTION>
                                                                           MARCH 31       DECEMBER 31
                                                                             1998            1997
                                                                          ---------       ---------
                                                                         (unaudited)
<S>                                                                       <C>             <C>      
                                                  ASSETS
Current assets:
   Accounts receivable, net of allowances                                 $  59,703       $  66,369
   Inventories                                                               33,048          32,426
   Prepaid expenses and other assets                                          4,863           3,550
                                                                          ---------       ---------
                          Total current assets                               97,614         102,345

Property, plant and equipment, net                                          101,337          99,994
Goodwill, net of amortization                                               122,068         122,882
Other assets, net                                                            12,709          12,963
                                                                          ---------       ---------
                          Total assets                                    $ 333,728       $ 338,184
                                                                          =========       =========

                                   LIABILITIES AND STOCKHOLDERS' EQUITY 
Current liabilities:
   Current installments of long-term debt                                 $  11,667       $  11,667
   Accounts payable                                                          32,886          42,422
   Accrued liabilities                                                       15,859          22,611
                                                                          ---------       ---------
                          Total current liabilities                          60,412          76,700

Long-term debt, excluding current installments                              195,286         188,743
Post retirement benefit liability                                             4,065           4,081
Deferred income tax liability                                                 5,945           4,169
                                                                          ---------       ---------

                                                                            265,708         273,693
                                                                          ---------       ---------

 Senior exchangeable preferred stock, 3,000 shares authorized,
   1,200 shares issued                                                       32,277          30,545
                                                                          ---------       ---------

Stockholders' equity:
     Common stock, par value $.01 authorized and issued 1,000 shares             --              --
     Additional paid in capital                                              41,925          41,675     
     Retained earnings (deficit)                                             (6,182)         (7,729)
                                                                          ---------       ---------
                          Total Stockholders' equity                         35,743          33,946
                                                                          ---------       ---------
                          Total liabilities and stockholders' equity      $ 333,728       $ 338,184
                                                                          =========       =========
</TABLE>


          See accompanying notes to consolidated financial statements.

                                       -1-
<PAGE>   4

                      DOANE PRODUCTS COMPANY AND SUBSIDIARY

                        CONSOLIDATED STATEMENTS OF INCOME
                (DOLLARS IN THOUSANDS, EXCEPT PER SHARE AMOUNTS)

<TABLE>
<CAPTION>
                                                             THREE MONTHS
                                                             PERIOD ENDED  
                                                               MARCH 31, 
                                                   ------------------------------
                                                       1998               1997
                                                   -----------         ----------
                                                     
<S>                                                <C>                      <C>            
Net sales                                          $  144,497          $  141,741
Cost of goods sold                                    119,967             122,725
                                                   ----------          ----------
Gross profit                                           24,530              19,016

Operating expenses:
Promotion and distribution                              8,434               7,881
Selling, general and administrative                     5,650               3,966
                                                   ----------          ----------
Income from operations                                 10,446               7,169
      
Interest expense, net                                   5,422               5,672    
Equity in earnings of joint venture                       (27)                 --
Other expense, net                                         (4)                (62)    
                                                   ----------          ----------
Income (loss) before taxes                              5,055               1,559
Income tax expense                                      1,776                 564
                                                   ----------          ----------

Net income                                         $    3,279          $      995
                                                   ==========          ==========

Net income (loss) applicable 
  to common stock                                  $    1,547          $     (547)

Basic net income (loss) 
  per common share                                 $    1,547          $     (547)

Weighted average shares outstanding                     1,000               1,000
                                                   ==========          ==========


</TABLE>


          See accompanying notes to consolidated financial statements.


                                       -2-
<PAGE>   5

                      DOANE PRODUCTS COMPANY AND SUBSIDIARY

                      CONSOLIDATED STATEMENTS OF CASH FLOWS
                             (DOLLARS IN THOUSANDS)

<TABLE>
<CAPTION>
                                                                                    THREE MONTH         
                                                                                PERIOD ENDED MARCH 31, 
                                                                             1998                 1997    
                                                                        --------------       ----------------
                                                                           (unaudited)         (unaudited)
<S>                                                                    <C>                   <C>            
Cash flows from operating activities:
    Net income                                                         $         3,279       $           995

Items not requiring cash:
    Depreciation and amortization                                                2,918                 2,601
    Amortization of deferred debt issuance costs                                   297                   281
    Deferred tax expense                                                         1,776                   583
    Deferred commodity credit                                                       --                   521
    Other                                                                          (76)                   72
Changes in working capital components                                          (11,557)              (11,890)
                                                                       ---------------       ---------------

        Net cash used in operating activities                                   (3,363)               (6,837)
                                                                       ---------------       ---------------

Cash flows from investing activities:
    Proceeds from sale of property and equipment                                    --                     1
    Capital expenditures, including interest capitalized                        (3,355)               (5,711)
    Increase in debt issuance costs                                                 --                   (91)
    Other                                                                          (75)                 (151)
                                                                       ---------------       ---------------

        Net cash used in investing activities                                   (3,430)               (5,952)
                                                                       ---------------       ---------------

Cash flows from financing activities:
    Net borrowings under revolving credit agreement                              9,465                13,725
    Proceeds from issuance of long-term debt                                        --                 1,668
    Principal payments on long-term debt                                        (2,922)               (2,604)
    Contributed Capital                                                            250                    --
                                                                       ---------------       ---------------

        Net cash provided by financing activities                                6,793                12,789
                                                                       ---------------       ---------------

        Increase in cash and cash equivalents                                       --                    --
Cash and cash equivalents, beginning of period                                      --                    --
                                                                       ---------------       ---------------

Cash and cash equivalents, end of period                               $            --       $            --
                                                                       ===============       ===============
</TABLE>


          See accompanying notes to consolidated financial statements.


                                       -3-
<PAGE>   6

                      DOANE PRODUCTS COMPANY AND SUBSIDIARY

                   NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
                (DOLLARS IN THOUSANDS, EXCEPT PER SHARE AMOUNTS)

                                   (Unaudited)
1.   Basis of Presentation

The interim consolidated financial statements of Doane Products Company (the
"Company"), included herein, have not been audited by the Company's independent
accountants. The statements include all adjustments, such as normal recurring
accruals, which management considers necessary for a fair presentation of the
financial position and operating results of the Company for the periods
presented. Operating results for the prior year periods include certain
reclassifications to conform with the current year presentation. The statements
have been prepared by the Company pursuant to the rules and regulations of the
Securities and Exchange Commission. Accordingly, certain information and
footnote disclosures normally included in financial statements prepared in
conformity with generally accepted accounting principles have been condensed or
omitted pursuant to such rules and regulations. The operating results for
interim periods are not necessarily indicative of results to be expected for an
entire year. The accounting policies used in preparing these financial
statements are the same as those summarized in the Company's Annual Report on
Form 10-K/A for the fiscal year ended December 31, 1997.

The Company's interim consolidated financial statements should be read in
conjunction with the financial statements and notes thereto contained in the
Company's Annual Report on Form 10-K/A for the fiscal year ended December 31,
1997 (including related exhibits), and the Company's Amendment No. 1 on Form S-3
to Form S-1 Registration Statement (File No. 33-98110) relating to the issuance
of $160,000 principal amount of the Company's 10 5/8% Senior Notes due 2006 (the
"Senior Notes").

2.   Inventories

The composition of inventories at the balance sheet dates was as follows:

<TABLE>
<CAPTION>
                                                                               MARCH 31, 1998  DECEMBER 31, 1997
                                                                               --------------  -----------------
<S>                                                                              <C>             <C>       
        Raw materials .....................................................      $    7,888      $    8,449
        Packaging materials ...............................................          11,225          10,735
        Finished goods ....................................................          13,935          13,242
                                                                                 ----------      ----------
                                                                                 $   33,048      $   32,426
                                                                                 ==========      ==========
</TABLE>

3.   Commitments and Contingencies

The Company is party, in the ordinary course of business, to certain claims and
litigation. In management's opinion, the resolution of such matters is not
expected to have a material impact on the financial condition or results of
operations of the Company.




                                       -4-
<PAGE>   7

4.   Subsequent Events

Senior Credit Facility

Effective April 13, 1998, the Company amended its senior credit facility
pursuant to the Second Amended and Restated Revolving Credit and Term Loan
Agreement (the "Senior Credit Facility"). Under the Senior Credit Facility
funding was increased under the "Term Loan Facility" from the outstanding
balance of $31,795 to $41,794 and a new $7,000 purchase money facility was
created, which may be drawn upon at a later time. The "Revolving Credit
Facility" remains at $25,000. The term of the Senior Credit Facility has been
extended from September 30, 2000 to September 30, 2001. Concurrent with the
extension of the term of the facility, the amortization of the Term Loan
Facility has been extended and quarterly principal payments reduced, initially
from $2,917 to $2,500.

The Company has the option to draw funds at either a Base Rate or LIBOR Rate
plus an Applicable Margin, which margin is determined from a pricing grid
predicated upon the ratio of Consolidated Total Debt to Consolidated EBITDA. In
general the LIBOR margins have decreased by .375% and the Base Rate margins have
decreased by .5%.

The predecessor agreement required the Company to cause the aggregate principal
amount of all Revolving Credit and Swing Loans to be less than $7,500 for a
minimum period of 30 consecutive days each fiscal year, which provision,
together with the Excess Cash Flow Recapture provision, has been eliminated.
Additionally, certain financial covenants have been amended consistent with the
extended term of the facility.

Ipes Iberica, S.A. Acquisition

On April 17, 1998 the Company purchased 100% of the outstanding stock of Ipes
Iberica, S.A. ("Ipes") for $28.3 million. Ipes is a private label pet food
manufacturer located in Spain with 1997 net sales of $21.1 million. The
transaction was financed through a $20.9 million non recourse facility provided
by the HSBC Investment Bank, Plc. in Spain, and $7.4 million from the Company's
Senior Credit Facility.



                                       -5-
<PAGE>   8
 
                      DOANE PRODUCTS COMPANY AND SUBSIDIARY
                         PART I - FINANCIAL INFORMATION

Item 2.  Management's Discussion and Analysis of Financial Condition and
         Results of Operations

Reference is made to Notes to Consolidated Financial Statements and Management's
Discussion and Analysis of Financial Condition and Results of Operations
presented in the Registrant's Annual Report on Form 10-K/A for the fiscal year
ended December 31, 1997.

The following table sets forth, for the periods indicated, the percentage which
the items in the Consolidated Statement of Operations bear to net sales and the
percentage change of such items compared to the indicated prior period.

<TABLE>
<CAPTION>
                                                               Three months ended March 31,  
                                                        1998                               1997                  % Change
                                                  -----------------                  -----------------           --------
                                                                  (Dollars in thousands)
<S>                                               <C>       <C>                      <C>       <C>               <C> 
Net sales                                         $144,497    100.0%                 $141,741    100.0%               1.9%
Cost of goods sold                                 119,967     83.0                   122,725     86.6               (2.2)
                                                  --------  -------                  --------  ------- 
Gross profit                                        24,530     17.0                    19,016     13.4               29.0 
Operating expenses:                             
Promotion and distribution                           8,434      5.8                     7,881      5.5                7.0
Selling, general and administrative                  5,650      3.9                     3,966      2.8               42.5
                                                  --------  -------                  --------  -------
 Income from operations                             10,446      7.3                     7,169      5.1                46.1

Interest expense, net                                5,422      3.8                     5,672      4.0                (4.4)
Equity in earnings of joint venture                    (27)    (0.0)                      -        -                  -
Other expense, net                                      (4)    (0.0)                      (62)    (0.0)              (93.5)
                                                  --------  -------                  --------  -------
Income before taxes                                  5,055      3.5                     1,559      1.1               224.2
Income tax expense                                   1,776      1.2                       564      0.4               214.9
                                                  --------  -------                  --------  -------           
 Net income                                       $  3,279      2.3%                 $    995      0.7%              229.5%
                                                  ========  =======                  ========  =======               =====
</TABLE>

RESULTS OF OPERATIONS

Three Months Ended March 31, 1998 compared to Three Months Ended March 31, 1997

     Net Sales.  Net sales for the three months ended March 31, 1998 increased 
1.9% to $144.5 million from $141.7 million in the same period in 1997.  Pet
food net sales increased 3.2% to $136.0 million for the three months ended
March 31, 1998 from $131.8 million in the same period in 1997.  Volume
increases resulted in a 5.0% revenue increase, which was reduced by price
declines of 1.9% primarily for cost plus contracts.

     Gross profit.  Gross profit for the three month period ended March 31,
1998 increased 29.0% to $24.5 million from $19.0 million in the same period in
1997.  Of this increase, approximately 23.8% resulted from improvements in pet
food margins due to reductions in certain raw material costs, and approximately
4.1% was due to the volume gains described above.  The remaining 1.1% was a
result of non pet food products.

     Promotion and distribution expense.  Promotion and distribution expense
increased 7.0% to $8.4 million for the three months ended March 31, 1998 from
$7.9 million in the same period in 1997.  Such increase was due to expenses
resulting from increases in variable sales promotions, incentive discounts, and
brokerage costs on volume gains.

     Selling, general and administrative expense.  Selling, general and
administrative expense increased 42.4% to $5.7 million for the three months
ended March 31, 1998 from $4.0 million in the same period in 1997 primarily as a
result of increases in (i) salaries and related fringe benefits, (ii)
professional fees and (iii) amortization and depreciation.

Income from operations.  Income from operations for the three months ended March
31, 1998 increased 46.1% to $10.4 million from $7.2 million in the same period
in 1997.  Income from operations as a percent of net sales increased to 7.3% for
the three months ended March 31, 1998 from 5.1% in the same period in 1997 due
to improved pet food margins and volume gains.

     Interest expense.  Interest expense decreased to $5.4 million for the
three months ended March 31, 1998 from $5.7 million in the same period in 1997
primarily due to an overall reduction in borrowings under the Doane Credit
Facility.

     Net income.  Net income for the three months ended March 31, 1998
increased to $3.3 million from $1.0 million in the same period in 1997 due to
increased pet food margins and volume gains.
  


                                       -6-
<PAGE>   9

LIQUIDITY AND CAPITAL RESOURCES

For the three month period ended March 31, 1998, cash used in operating
activities was $3.4 million compared to $6.8 million in the same period in 1997,
which was primarily due to a $3.1 million increase in net income before non cash
charges. Working capital at both March 31, 1998 and March 31, 1997 was $37.2
million and the working capital increase for the three month period ended March
31, 1998 was $.3 million less than in the same period in 1997.

Net cash used in investing activities was $3.4 million for the three month
period ended March 31, 1998 which was $2.6 million lower than the same period in
1997. This reduction was due to expenditures for the 1997 Expansion Projects
that exceeded the capital expansion programs in the first quarter of 1998. The
1998 capital expansion programs included the purchase of a building in Clinton,
Oklahoma (in March 1998), which will be refurbished to manufacture dry pet food,
and warehouse expansion projects at two existing facilities.

Net cash provided by financing activities for the three month period ended March
31, 1998 decreased by $6.0 million from the same period ended in 1997 and was
the direct result of improvements in net income and reductions in capital
expansion programs previously noted.

At March 31, 1998, the Company had borrowing capacity in the amount of $14.4
million under the Revolving Credit Facility, which was net of $1.1 million for
outstanding letters of credit. Long term debt outstanding at March 31, 1998
consisted of $160.0 million Senior Notes, the Term Loan Facility in the amount
of $31.8 million, and Industrial Revenue Bonds in the net amount of $5.7
million.

It is expected that existing manufacturing facilities, notwithstanding the
recent capital expenditures on new and existing facilities, will not be
sufficient to meet the Company's anticipated volume growth for the next several
years. Accordingly, the Company anticipates that additional facilities will be
necessary in order to support continued growth of the Company's business. The
Company has continued to examine alternatives for expanding it's business either
through construction of additional manufacturing capacity or acquisition of
manufacturing assets. Such potential acquisitions could include acquisitions of
operating companies. The Company intends to finance such expansions or
acquisitions with borrowings under existing or expanded credit facilities, or
the issuance of additional equity, depending on the size of the proposed
expansions or acquisitions.

On April 13, 1998 the Company amended and restated the Senior Credit Facility,
which increased the Term Loan Facility borrowings by $10.0 million, and provided
a new Purchase Money Facility of $7.0 million to be drawn at a future date.
Additional changes include; (i) reduction of interest rate margins, (ii)
extension of final maturity, (iii) reduction of quarterly installment amounts,
and (iv) revised schedule of financial covenants.

On April 17, 1998 the Company purchased 100% of the outstanding stock of Ipes
Iberica, S.A. ("Ipes") for $28.3 million. Ipes is a private label pet food
manufacturer located in Spain with 1997 net sales of $21.1 million. The
transaction was financed through a $20.9 million non recourse facility provided
by the HSBC Investment Bank, Plc. in Spain, and $7.4 million from the Company's
Senior Credit Facility.



                                       -7-
<PAGE>   10

                      DOANE PRODUCTS COMPANY AND SUBSIDIARY
                                     PART II


Item 6.  Exhibits and Reports on Form 8-K

           (a)    Exhibits Index

                  27.1        Financial Data Schedule

           (b)    Reports on Form 8-K

                  None




                                       -8-
<PAGE>   11

                     DOANE PRODUCTS COMPANY AND SUBSIDIARY

                                    PART II

                               OTHER INFORMATION

                                   SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                        DOANE PRODUCTS COMPANY



August 6, 1998                          By  /s/ THOMAS R. HEIDENTHAL
                                            ------------------------------------
                                            Thomas R. Heidenthal
                                            Senior Vice President and
                                            Chief Financial Officer






                                      -9-
<PAGE>   12

                               INDEX TO EXHIBITS

<TABLE>
<CAPTION>
EXHIBIT NO.         DESCRIPTION
-----------         -----------
<S>            <C>
   27.1        Financial Data Schedule
</TABLE>