Senior Brisbane riders Matt McGillivray and Dale Smith will remain sidelined after an inquiry into their failure to give urine samples at Eagle Farm.

Stewards stood the pair down on Saturday and ordered them to provide samples at the Sunshine Coast on Sunday and then front an inquiry on Monday.

Both cited dehydration from wasting and drinking minimal fluids and asked for blood tests to be taken but that option is not available to stewards.

Tests were carried out on all jockeys at Saturday's Eagle Farm meeting but McGillivray and Smith were unable to provide samples even after stewards gave them until 7pm.

They both produced samples on Sunday.

Chief steward Peter Chadwick said Monday's Inquiry determined both jockeys would remain stood down until the analyst's results were returned from Sunday's tests.

It is understood the test results should be known by the end of the week.

Chadwick said Saturday's testing was part of a QRIC operation with all jockeys riding at Eagle Farm directed to provide samples within an hour of their last ride.

QRIC Integrity Investigations Team and stewards conducted further testing of riders at Eagle Farm and Doomben trackwork on Monday morning.

Chadwick said as a result of the operation four riders were found to be unlicensed.

Eighteen samples were sent to Racing Analytical Services Limited and two samples taken on Monday will be subject to further testing but no riders were stood down.