Effects of changes in diet energy density and milking frequency and a single injection of cabergoline at dry-off on feeding behavior and rumination time in dairy cows

Summary: Typically, dairy cows have their milk production artificially ceased generally 60 d before the date of expected calving in a process termed “dry-off.” Dry-off can be abrupt; that is, diet and milking frequency remain unchanged until the day of last milking, or gradual, aiming to reduce milk yield before the onset of the dry period. Abrupt dry-off may be facilitated by administration of prolactin-release inhibitors such as cabergoline. We examined the effects of dietary and milking frequency changes during 1 wk before the dry-off day, as well as injection of cabergoline following the last milking, on automatically monitored feeding behavior and rumination time in high-yielding (.15 kg/d at dry-off) cows. Reducing diet energy content by diluting the lactation diet with straw induced consistent feeding behavior changes before dry-off. The effects of gradual milking cessation were unclear, while cabergoline reduced feeding behavior for approximately 24 h.