Behaviour and percentage eye-white in cows waiting to be fed concentrate—A brief report

A major task when developing methods of assessing animal welfare is to identify observable external indicators of internal subjective feelings. In this paper, we tested the hypothesis that the percentage of white in the eyes would change as a response to two emotional stimuli; waiting to be fed concentrate and acquiring this food. Twelve dairy cows in a tie-stall were observed for eye-white percentage and behaviour (continuous sampling), one trial day per cow, in a standard daily situation in which a stockman entered the house and fed all animals with concentrate feed within 10 min. The eye-white percentage increased significantly, although moderately, during the first minute and was kept moderately high during the waiting period. After food was obtained, the eye-white percentage decreased compared to the base level. We suggest that a high eye-white percentage may reflect a strong emotional response.