A new study exploring how to measure emotions in cows suggests it may be possible to tell how a cow is feeling from the position of its ears.
It also shows that like many of our pets, cows display visible and recognisable signs of pleasure at being stroked.
A study of 13 cows was conducted by scientists at animal welfare charity World Animal Protection, and published in this month’s journal Applied Animal Behaviour Science.
According to the authors of the study, when cows were stroked for five minutes – an experience that put them into a calm and relaxed state – they performed either a backward or hanging ear posture, where the ear fell loosely, perpendicular to the head.
This contrasted with the more usual position of the ear before and after stroking of either upright or forwards. Previous studies have suggested ear position may provide clues to how sheep and pigs are feeling, but this is the first to look at whether cows display similar traits.
World Animal Protection’s sentience manager Helen Proctor, who co-authored the study, said: “Although these results need further validation using different stimuli, they do indicate the use of ear postures may provide a quick, non-invasive and low-cost measure to assess the emotional state of dairy cows.”
“Because emotions are defined as short lasting, it is possible ear postures may provide both an immediate indicator of the cow’s emotional state and also be indicative of a longer-lasting mood state.
“Understanding animal emotions is crucial if we are to improve animal welfare as emotions play a major role in an animal’s mental well-being.
“Research into positive emotions must therefore continue, and reliable indicators of positive emotions need to be developed and applied in practice so animal welfare can continue to improve.”
The study recorded nearly 400 observations of the 13 cows using stroking on their head, neck and withers as a positive stimulus.
The authors say the ear positions most prevalent when the cow was not being stroked (an upright or forward ear posture) were markedly different to those adopted when the positive stimulus of stroking was being undertaken.
World Animal Protection UK is hopeful the study will be of use when working with the dairy industry in their programmes and understanding of their cows.