Animal activity, in combination with physiological factors, can be used for early disease detection in dairy cattle. An initial study determined the impact of flunixin meglumine (FM), a non-steroidal anti-inflammatory drug, on activity measures, dry matter intake (DMI) and milk production during experimentally induced Escherichia coli mastitis. A total of 24 primiparous and multiparous lactating dairy cows were challenged with E.coli 727 in one quarter. Of the 24 E.coli challenged animals, 12 were administered FM at 0.002 µg/45.5kg of body weight at the onset of clinical mastitis signs. The remaining 12 cows were untreated. An additional 11 cows were infused with 1 mL of sterile phosphate-buffered saline, and served as the control group. Activity measures were collected through the use of the Afi PedometerPlus© and HOBO® data loggers. E.coli mastitis altered animal activity and improvement in DMI and milk production of animals given FM was observed, thus providing evidence for the use of an NSAID as supportive therapy for mastitis. Additionally, activity and blood metabolites concentrations were collected and analyzed from periparturient dairy cows at the Virginia Tech Dairy Center to determine the likelihood of disease occurrence. Primiparous and multiparous Holstein, Jersey, and Crossbred dairy cows were monitored for daily rest bouts, rest duration, and rest time throughout the pre and postpartum periods. Activity measurements were collected using Afi PedometerPlus© pedometers. It was concluded that evaluation of activity changes, and comparison of deviations from healthy herdmates, could allow producers to utilize activity monitoring to proactively manage dairy herd health. / Master of Science

Animal behavior can be used to detect disease and well-being in dairy cattle. In this dissertation, we evaluated the accuracy of an accelerometer to measure step activity, lying time, and lying bouts in pre-weaned dairy calves. The output from the accelerometer was correlated with behavioral measurements taken from video footage. The accelerometer proved to be accurate in identifying step activity (r = 0.99), lying time (r = 0.99), and lying bouts (r = 0.99). The accelerometer was then used to detect behavioral changes occurring around respiratory disease events in pre-weaned calves. Activity declined 1 d prior to clinical disease onset, and this decline persisted for 3 d post-diagnosis. Furthermore, lying bouts declined beginning 2 d prior to diagnosis, and this effect persisted after diagnosis as well. However, aside from a slight reduction in milk intake, feeding behavior was not different between diseased and healthy calves. These data suggest that activity and lying behaviors may be a better measure than feeding behaviors for detection of respiratory disease in pre-weaned dairy calves. Dystocia has detrimental effects on both periparturient dairy cows and newborn calves. We administered a non-steroidal anti-inflammatory drug, meloxicam to periparturient dairy cattle. Treatments included administration prior to calving (MEL-PRE, n = 60), post-calving (MEL-POST, n = 69), or a negative control (CTL, n = 65). We measured the length of labor to determine which cows had easy or difficult calvings. Eutocic MEL-PRE animals produced 6.8 kg/d more milk than eutocic CTL. Regardless of calving difficulty, MEL-PRE animals produced more milk fat, protein, and lactose (kg/d) than the CTL. Additional research is needed to determine appropriate treatments for dystocic calvings. Calves born during the above trial were monitored to determine if meloxicam administration prior to calving impacted newborn calf health and behavior. Calves born difficultly displayed fewer lying bouts for the first few days after birth when compared to calves born easily. No effect of treatment or calving difficulty was noted on calf health. Additional research examining intervention strategies aimed at improving well-being of calves born difficultly is needed. / Ph. D. / Public interest in animal welfare continues to grow, making it increasingly important that the dairy industry evaluates management practices to further advance animal well-being. Animal behavior can be used to detect disease and well-being in dairy cattle. We monitored activity and lying behaviors around respiratory disease events in calves. This was done to determine which behaviors were altered by respiratory disease, and if these behaviors could be used to detect respiratory disease events earlier. Activity and lying behaviors were measured using an accelerometer that works similarly to a pedometer. We were able to identify that calves that would manifest with respiratory disease would display a decline in activity prior to clinical disease diagnosis. These data suggest that activity measures could be a promising indicator for respiratory disease detection in calves, and allow for earlier detection. Parturition, the act of a dairy cow giving birth, is a stressful, risky time period as disease incidences and death are high. Furthermore, an immense amount of inflammation occurs after calving due to parturition as well as metabolic stress associated with milk production. Therefore, in this study, we administered a non-steroidal anti-inflammatory drug (meloxicam) to alleviate inflammation. Treatments included administration prior to calving (MEL-PRE), post-calving (MEL-POST), or a negative control (CTL). We measured the length of labor to determine which cows had easy or difficult calving events. Animals that received meloxicam prior to calving and calved easily produced 6.8 kg/d more milk than CTL animals that calved easily. Additional research is needed to determine appropriate treatments for animals that calve difficultly. Calves born during the above trial were monitored to determine if meloxicam administration prior to calving impacted newborn calf health and behavior. No effect of treatment or calving difficulty was noted on calf health. Additional research examining intervention strategies aimed at improving well-being of calves born difficultly is needed.