A Queensland jockey has been stood down for allegedly providing a sample of fake urine to stewards.
The female jockey gave the sample to Queensland Racing Integrity Commission stewards at Rockhampton last Sunday when they carried out no-notice testing at the meeting.
On analysis by Racing Analytical Services Limited, the sample was found to be inconsistent with human urine.
The QRIC said in a statement on Thursday, the jockey denied providing a sample that was not her urine.
QRIC Commissioner Ross Barnett said it was a concerning incident where a racing participant had allegedly made a pre-meditated decision to thwart the drug testing regime.
"Any planned deception to deliberately provide a false sample would only be undertaken by a person with something to hide," Barnett said.
"All racing participants have an obligation to present to work without prohibited substances in their system for the safety of other participants and for the welfare of animals."
The jockey has been stood down until the conclusion of the inquiry.