A thoroughbred retraining program involving Hunter Valley prison inmates appears to be going from strength to strength.

Since the program started five years ago, hundreds of horses have gone to Muswellbrook's St Heliers Correctional Centre, where they have been paired with inmates.

It is part of Racing New South Wales' Thoroughbred Rehabilitation Program, with horses going on to have eventing and dressage careers.

Spokesman Charles Moon said it had been a great success.

"As an industry we are lucky to see our equine athletes every day in New South Wales, but when they come to a decision of retirement, there is an opportunity to say, look the horses aren't just going to go to the paddock," he said.

"You know there is a second career, and working with Corrective Services NSW and especially with the joint venture program we have with them, it just provides an opportunity to work with some good people and to work with committed horse people."

Racing NSW says every effort is made to ensure horses have a future beyond racing. ( Supplied )

Benefits for horse and rider

The thoroughbred retraining program at the Hunter Valley jail has been lauded for helping horse and rider.

Mr Moon said there had been enormous benefits for everyone involved.

"This program allows both horse and human the benefits of a second career and a second chance," he said

"It is amazing that each horse will have their own personality, and that is the same with humans, and doing this retraining and career work where they can learn some new skills, they are allowed that individual flair.

"They are suited to particular second careers, and when there are inmates themselves who are looking for a second chance after making a mistake in their earlier days, horse can bring out that possibility for them."

Horses helping ex-soldiers with PTSD

The program is also playing a role in helping ex-Australian soldiers to recover from post-traumatic stress disorder (PTSD).

It involves pairing horses with emotionally-damaged ex-solders at the program's Sydney base at Canterbury Racecourse.

"It is amazing the way that an animal won't judge a human. An animal will work with any human," Mr Moon said.

"The Australian infantry has just had decades of association with horses, and so to work with charities, especially those with PTSD, is something that we would really be encouraging our program to grow to."

The program comes at a time when there is mounting pressure to curb so-called wastage in the horse racing industry.

Wastage, involving the killing of slow dogs, was part of the reason the NSW Government banned greyhound racing.

It has prompted animal welfare groups to call for more strategies to cut wastage in horse racing.

Racing NSW said every effort was made to ensure horses had a future beyond their racing years.