Griffith, Abigail Susanne2014-08-242014-08-242014-08-23vt_gsexam:3499http://hdl.handle.net/10919/50414Activity and milk components were examined around disease onset in the periparturient period. Cows were monitored for daily rest bouts, rest duration, rest time, and step activity from -21 to +30 d relative to calving. Lactose concentration, fat to protein ratio (F:P), and milk yield were monitored. Diseases analyzed were assisted calving, mastitis, subclinical ketosis (SK), and a multiple disease category (MULTI) for animals who experienced more than one disease. Rest bouts decreased (d 0), step activity increased (d 0), and rest duration decreased (d -1) in animals that experienced assisted calving compared to controls. Mastitic cows showed fewer rest bouts (d -4, -3, -2, -1, and 0), increased activity (d -4, -2, and -1), decreased rest time (d -6, -5, -4, and -2), and decreased milk yield (d -4, -2, -1, 0) compared to controls. Cows with SK showed increased activity (d -5, -4, -3, and -2), decreased rest duration (d -7, -6, -5, -4, and -3), rest time (d -7, -6, -5, -4, -3, and -2), milk yield (d -4, -3, -2, -1, and 0) and lactose concentration (d -3, -2, -1, and 0) compared to controls. Animals categorized as MULTI showed increased activity (d -6, -5, -4, -3, and -2), increased F:P (d -2, -1 and 0), decreased rest time (d -5, -4, -3, and -2), and decreased lactose concentration (d -6, -5, -4, -5, -3, -2, -1, and 0) compared to controls. Deviations in activity and milk components could be used to proactively manage herd health.ETDIn CopyrightbehaviordeviationsdiseaseThesis