Tasmania lags the rest of Australia in welfare regulations and rehoming provisions for harness racing horses, an independent review says.
The report also found the island state's racing model has brought about a "stifling" of competition, particularly in lower-class events which had been "monopolised" by one trainer.
The review into accusations of team driving, race fixing and animal cruelty in the industry was called by the state government in March after an ABC investigation.
An interim report released on Wednesday calls for a suite of reforms including minimum welfare standards for racehorses and regulations around their post-career fate.
Report author, racing integrity expert Ray Murrihy, said "disturbing" images in media reports of the slaughter of an unidentified horse were an affront to most fair-minded people.
He said the images, although dated, were upsetting especially as they involved a horse that had recently finished their career.
Mr Murrihy said while Tasmania had taken some significant steps forward, rehoming provisions were behind those being progressed in mainland states.
There was no provision in the rules of racing to compel owners to take full responsibility for rehoming a horse, he said.
His recommendations include rules to ensure owners take a whole-of-life approach for the best possible outcome for a horse no longer suitable for racing.
Mr Murrihy said Tasmania's structure for enforcing harness racing horse welfare rules was unwieldy and not conducive to good outcomes.
He said Tasmania did not compare favourably with welfare practices of other states which have a mandatory regulated path for horses post-racing.
Mr Murrihy noted the vast majority of horses in Tasmania were well cared for or suitably rehomed.
Racing Minister Felix Ellis said the report's recommendations reinforced those made in an earlier review, some of which the state government had adopted.
Mr Ellis said other recommendations, including around minimum standards for stocking, would be considered as part of the development of a Tasracing code of practice for equine welfare and management.
Mr Murrihy's final report is expected to be completed in late 2023.
He said one trainer had legally taken advantage of the state's racing model to acquire a number of mainland horses at the end of their careers.
"This has evolved into monopolisation by that trainer of lower-rating races, whereby he will regularly have the majority or all runners in those races," Mr Murrihy said.
Mr Murrihy has recommended a new ratings system for races.
