Respected Sydney trainer Ron Quinton has been found guilty after two of his horses were found with elevated cobalt levels, but avoided a penalty because his feed was found to be the blame.

Quinton fronted a Racing NSW stewards inquiry on Thursday after pre-race urine samples taken from Boss Lane and Imanui in August revealed higher than permitted levels of cobalt.

The only penalty stewards imposed was to disqualify both horses from their positions in the races they contested.

Credit: AAP