Effect of milk cessation method at dry-off on behavioral activity of dairy cows

摘要

ABSTRACTDrying cows off at the end of lactation is a routine management practice in dairy operations. Most dairies in the United States and many other countries dry cows off abruptly (e.g., stop milking cows on a set day), which has been shown to affect cow comfort. Gradually reducing milk production is another approach to dry cows off, routinely used in some countries and herds. The objective of the study was to evaluate the effects of abrupt and gradual milk cessation and milk yield at the time on cow activity after dry-off. Daily lying time, number of lying bouts per day, average lying bout length, and steps taken per day by abruptly and gradually dried-off cows were monitored by data loggers for 2 wk before and after the final milking at the end of lactation. Gradual cows were milked once daily for the last week of lactation, and abrupt cows were milked as usual (3×/d) until the end of lactation. Gradual cessation of milking significantly reduced milk yield by the day of dry-off. After dry-off, gradual cows tended to have longer lying bouts than abrupt cows, but no other differences in cow activity between the 2 treatments were observed. Regardless of the dry-off method, the average length of a lying bout decreased by 4 min and total daily lying time decreased by 19 min after dry-off for each 5-kg increase in milk yield before dry-off. Lying behavior of primiparous cows was more affected by the level of milk yield at dry-off than that of older cows. A reduction in lying times with increasing milk yield may indicate discomfort due to the accumulating milk in the udder. Using a method that lowers milk production before dry-off and managing primiparous and multiparous cows separately around dry-off are beneficial for cow comfort after dry-off.