Live export sheep stressed and seasick in shipping pens, Queensland study finds.

Sheep get stressed and aggressive when put in conditions approved by Australia for live animal exports, a study has found.

The University of Queensland's Gatton campus tracked the effects of high-stocking density and sea motion on the welfare of sheep.

It found a 25-kilogram sheep showed signs of aggression and stress in crates set to the Australian shipping standard of 0.26m2 per animal.

They would need at least 20 per cent more space to improve their welfare, the researchers said, while acknowledging it may drive up export costs.

The study put sheep in different stocking densities on a platform and replicated the motions of a ship for one hour, a few times each day.

The animals' heart rates and behaviour were constantly monitored and recorded.

UQ's School of Veterinary Science professor Clive Phillips said the animals were stressed by the constant movement and being packed in together.

"In the high-stocking density, they were tending to push each other more and the heart rate responses showed that they were experiencing more stress," Professor Phillips said.

"We appreciate that giving sheep an extra 20 per cent space or even 30 per cent space would, or potentially could, dramatically reduce the profitability of exporting live sheep overseas.

"But if that is what the public requires for the sheep to be transported in a high-welfare situation, then it may be that is what needs to happen."

The UQ-funded research is due to be published mid-year.

All of the information contained on this page and the original article can be found: Live Export Sheep