Facial expressions of sheep can be utilised to accurately detect pain associated with livestock diseases such as foot-rot and mastitis, according to researchers at Cambridge University.
The researchers said their objective was to develop a 'pain scale' for adult sheep, that would be detected through the facial expression of sheep.
"The sheep pain facial expression scale (SPFES) was able to correctly identify sheep suffering from disease with a high degree of accuracy," the study said.
"Diseased sheep scored higher on the scale than controls on the day of disease identification and diseased sheep showed changes in their facial expression after treatment."
The abnormal facial expressions of diseased sheep reduced over time, and at recovery were in line with control sheep.
Control sheep did not change their facial expression over time.
Five scorers who were trained to use the developed scale also assessed the facial expressions of sheep.
The scorers were blind to treatment and session.
Scorers reliably and accurately identified changes in the facial expression of sheep with foot-rot over time, and scored control sheep consistently low over time.
"Prompt recognition of pain through the use of the scale will enable farmers and veterinarians to treat and manage their flocks better, reducing the impact of pain on their sheep, thus improving welfare and production," the researchers said.
"It is likely that the scale can be used for other conditions that are suspected of being painful such as pregnancy toxaemia where the administration of a non-steroidal anti-inflammatory is known to aid recovery."
