Genetics play a large factor in determining the temperament of sheep and how they react to stress, according to a study conducted by The University of Western Australia (UWA).

The researchers analyzed sheep DNA and found that the changes in sequences of the tryptophan hydroxylase gene could alter the protein structure of this enzyme, ultimately affecting how sheep respond to stress, UWA said in an announcement.

Lead researcher Luoyang Ding, a doctoral student from the UWA School of Agriculture & Environment and the UWA Institute of Agriculture, said the researchers focused on genes linked to serotonin and oxytocin, under the supervision of associate professor Dominique Blache, professor Shane Maloney, associate professor Jennifer Rodger and professor Mengzhi Wang.

“We found the gene markers (the special changes in tryptophan hydroxylase sequences) linked to the production of serotonin resulted in sheep that were calmer in nature and dealt with stress better,” Ding said. “By sequencing the tryptophan hydroxylase gene in sheep at an early age, we can get an indication of their stress levels and what could come later on as the sheep get older.”

Ding said a problem in livestock farming was that stress in animals made practices more costly and time consuming, and it was more difficult to care for stressed animals.

“The quality of the meat is also severely impacted by stress, with anxious sheep producing much tougher, darker and drier meat,” he said. “We hope these findings can help farmers improve the care of sheep and farming efficiencies by being able to understand the temperament of their sheep at an early age.”

Ding said it would also be interesting to find out if the gene markers could be used to estimate the risk of anxiety in people early on.

“It is clear that there is a definite chemistry at play in individuals who get stressed or anxious easily,” he said.

The research was made possible by a China Scholarship Council — The University of Western Australia Joint Scholarship by the UWA Scholarships Committee.