A Queensland country jockey has been suspended for a month and fined $500 after being found to have used modified spurs on a horse in a race.

Stewards at Dalby, west of Toowoomba, opened an inquiry into the post-race condition of Smarty Jack who won the second race on Saturday.

The inquiry heard a post-race veterinary examination showed the gelding had lacerations to the near and off-side lateral thorax.

In the opinion of the on-course veterinarian, the wounds were consistent with the use of spurs.

Stewards searched jockey Joshua King's race gear, and seized spurs that, in their opinion, appeared to be modified and therefore were not suitable for use.

King acknowledged the spurs were used on Smarty Jack in the race.

King was fined $500 for using modified spurs that were not approved by the stewards.

He also pleaded guilty to using his spurs in an improper manner.

King was suspended for a calendar month, to begin on February 8.

He has the right to an internal review.