The primary objective of the experiments described in this thesis was to use quantitative behavioral measures of livestock to evaluate animal welfare. In one study, the effects of a therapeutic drug in lame dairy cows were evaluated for alleviating pain associated with lameness and hoof trimming. Lameness pain was measured using lying and standing times as well as locomotion scoring. No effect on lameness indicators or milk production was found for hoof trimming or drug administration. In the second study, behaviors associated with maternal nutritional plane during gestation were measured in lambs. Lambs born to nutritionally restricted dams behaved differently from those born to adequately-fed dams after a pen change, implying a difference in adaptation to a stressful event. Continuing to find quantitative behavioral measures for pain and adaptation to stressors will aid in future work to improve livestock welfare.