Cortisol levels and anxiety-related behaviors in cattle.

This investigation was conducted to examine the relationship between cortisol levels and anxiety-related behavior in nine Angus/Hereford cows. In a non-stressful pasture setting, measures were taken of rumination, distance from another cow, and body position. In a stressful holding pen situation, measures were taken of vocalizations and resistance to entering a squeeze chute. Cortisol was measured in serum samples. Subjects with high levels of cortisol spent less time ruminating (p=0.007) and vocalized more (p=0.07) than subjects with low levels of cortisol. Regardless of statistical significance, all mean differences were in the predicted direction. Cortisol levels were correlated with time spent ruminating (p=0.004) and later entrance to the squeeze chute (p=0.10). All correlations were also in the predicted direction. These findings provide consistent support for the link between cortisol and anxiety-related behavior in beef cattle, and the findings have theoretical and practical implications.