Jockey Club Racecourses says it will be hit by a £1m reduction in profits after it was announced its courses will host 24 fewer races in 2015.
British Horseracing (BHA) published its fixture list, stating that there are not enough horses to sustain the number of races and "small-field, uncompetitive races" would be reduced.
The Jockey Club says it will have 340 fixtures compared to 364 in 2014.
"The fixtures not staged generate profits of circa £1m," it said.
The Jockey Club - the sport's largest commercial organisation in the UK - owns 15 courses in total, including Aintree, Cheltenham and Epsom Downs.
It is governed by the Royal Charter and all its profits are reinvested back in the sport.
The BHA, which announced a total of 1,471 fixtures for 2015, stated: "The principal focus for the fixture list was to address the issue of the growing number of uncompetitive, small-field races which are both unattractive for the punter and damaging to British Racing's international reputation.
"Put simply, the current horse population is not able to satisfactorily sustain the number of races we have staged in recent years.
"As such, while the fixture List is similar in size to 2014, and this is a position supported by all stakeholder groups, steps have been taken to address imbalances to ensure that more fixtures and races are staged at periods in the season when the supply of horses is better placed to meet the demands of the list."
Other highlights of the 2015 fixture list include:
- The 'new' Chelmsford City racecourse (formerly Great Leighs) has been allocated 57 fixtures for 2015 with its first meeting scheduled for Sunday 11 January.
- Wetherby will stage the first of its four Flat meetings in 2015 on 26 April with the others on 22 June, 13 July and 21 July.
- The Cheltenham Gold Cup is on 13 March and the Grand National on 11 April meaning a longer than usual gap of nearly four weeks between the two festivals.