Four racehorses rescued from an overturned float on Queensland's Bruce Highway remain under observation in a Caloundra veterinary clinic.

The Tony Gollan-trained Casual Choice, Jetsonic, Whiskey Allround and Frespanol were being taken to the Sunshine Coast racetrack on Saturday when the accident happened.

The truck slid down an embankment and came to rest on its side.

The driver and stable staff escaped injury but the horses were trapped and had to be sedated before being released by emergency services.

Gollan said at this stage it looked as though the horses had only suffered abrasions.

"The staff and rescuers were just awesome and it could have been much worse," Gollan said.