Jockey Beau Appo will begin a four-week suspension on Sunday after losing an appeal against his conviction for weighing in light in a race earlier this year.

The appeal attracted widespread attention as it was the latest incident in a string of similar cases across Australia this year.

Thd Queensland Civil and Administrative Tribunal dismissed his appeal last month but ordered Appo serve his sentence to start on December 1.

Appo was unsuccessful in an internal application into the suspension for weighing in light at Toowoomba when he rode Pieridae who won the last race on April 22 .

He was outed for four weeks and the horse disqualified after Appo weighed in 0.8kg under the allocated weight.

Appo claimed at the internal review he was not responsible as he had weighed out correctly.

He argued a gel pad used to make up the weight may have come off the saddle pack but reviewer Kane Ashby dismissed the application.

The matter went to a QCAT appeal which was unusual because it featured a demonstration of saddling a horse.

Appo's lawyer Jim Murdoch also argued penalties for jockeys were out of kilter with penalties for trainers found guilty of the offence.

QCAT member Robert King Scott found the stewards had been correct in their findings and interpretation of the rules.

He found the gel pack probably fell out in the stabling area before entering the parade ring and Appo, tired from a day's riding, had not noticed it missing when tightening the girth.

He sent the case back to stewards to impose the sentence from Sunday night.