Trainers Gai Waterhouse and Adrian Bott will answer charges next week relating to the substitution of horses in televised track gallops.

Waterhouse and Bott were charged with conduct prejudicial to the image and/or interests of racing - after they replaced three horses scheduled to work at Randwick on April 4 without notifying stewards.

Only horses entered to compete at Randwick on April 8 were eligible to gallop on the course proper.

Waterhouse and Bott did not enter a plea at the original hearing on April 11.

The training partnership was granted an adjournment to seek legal advice after being charged and will front the stewards next Thursday.

They acknowledged galloping Stampede, Fabrizio and Sort After in the colours and saddlecloths of Serena Bay, Debonairly and English.

Before the charge was laid, Waterhouse apologised for replacing the horses and insisted she had no intention of bringing racing into disrepute.

The horses were substituted because Serena Bay, Debonairly and English were not fit to gallop due to a variety of reasons.

Waterhouse said it was unfair she and Bott were charged and a warning would have been more appropriate.