Short communication: The effects of cabergoline administration at dry-off of lactating cows on udder engorgement, milk leakages, and lying behavior

Cabergoline is an ergot derivative with high affinity for the D₂ dopamine receptors whose dopaminergic effects cause inhibition of prolactin (PRL) secretion; thus, it could be considered a molecule that acts as a potential dry-off facilitator. One hundred ninety-nine Holstein cows (102 primiparous; 97 multiparous) producing ≥18 kg/d at dry-off were split in 2 treatments to evaluate the effects of diminishing PRL secretion at dry-off (between 70 and 50 d from the expecting calving date) on udder engorgement, milk leakage, and cow well-being after dry-off. Treatments consisted of a single i.m. injection of 5 mL of a solution containing 5.6 mg of cabergoline (CAB; Velactis, Ceva Santé Animal, Libourne, France) or 5 mL of saline solution as a placebo (CTRL). Each animal was evaluated for presence or absence of milk leakages during the 4 d following dry-off and udder engorgement was determined using a digital algometer. Lying behavior was recorded during 10 d after dry-off. Twenty-five cows from each treatment were randomly chosen and blood sampled at 3 and 15 d after dry-off, and again at 5 and 3 d before the expected calving date to determine serum PRL concentrations. Cows on CAB had lower serum PRL concentrations than cows on CTRL at 3 and 15 d after dry-off. Average udder engorgement was lower for cows on CAB than for cows on CTRL following dry-off, and it decreased as days after dry-off increased. The overall incidence of milk leakage in cows on CAB (3.1 ± 0.88%) was 73.5% of that obtained in cows on CTRL (11.7 ± 1.64%); cows on CAB had 0.2 lower odds of incurring milk leakage than cows on CTRL. The day following dry-off, CAB cows lied about 1.5 h/d more than cows on CTRL. We conclude that i.m. administration of 5.6 mg of cabergoline at dry-off effectively reduces PRL secretion, udder engorgement, and milk leakages, and improves lying time the day following dry-off.