Observing cows and heifers close to calving is important to identify if the animal is experiencing calving difficulty. The National Animal Health Monitoring study for dairy tells us that dystocia occurs in 11 percent of calvings for heifers and 19 percent of calvings for cows. Ideally we should observe animals at all times, says Heather Dann, research scientist with the Miner Institute. But this is not practical or even possible for most dairies. Approximately 50 percent of U.S. dairies observe cows close to calving every three hours or less during the day and every five hours or less at night.

Recent research from the University of Edinburgh indicates that with increasing herd size, herdsmen are responsible for more cows and therefore less time is available for individual cow attention. The researchers suggest that an automated system for monitoring cows during the transition period could help minimize cow and calf losses associated with dystocia.

To aid in the development of a system, the researchers systematically quantified the behavior of cows during the 24 hours before calving and during a 24-hour period of late pregnancy. The daily duration of lying decreased, walking increased and ground-licking increased for the calving period compared to the late pregnancy period. Lying and walking bouts increased and tail raising frequency were higher during the calving period than the late pregnancy period. Behavioral changes varied in how consistent they were between cows. Lying bouts and tail raising frequency were the most consistent. The most useful observations were made within the final six hours before calving, says Dann. The number of lying bouts increased twofold indicating restlessness and the number for tail raises increased sevenfold.