It’s 6:00 p.m. A farmer is finishing chores on the dairy and is about to head in for the night, when he/she notices 1157, a heifer that looks like she’s close to calving. The farmer decides to check on the heifer in a few hours to monitor her progress. At 9:00 p.m. the farmer checks 1157 again, but there are no new developments, so he/she decides to come back at midnight. But yet again, when the farmer checks 1157, there’s still no progress. Now, tired, sleep deprived, and frustrated, the farmer decides to head to bed and check her in the morning.
All too many times I have either been part of this story or heard it as an everyday frustration from dairy farmers. Well, there is finally some good news—precision dairy technologies can predict calving events. With a computer or a mobile device, farmers can monitor their cows from the comfort of their own homes.
Out with the old…
Currently, farmers use visual signs such as udder firmness, pelvic ligament relaxation, and vulva swelling as indicators of a time frame for calving. While these old but true methods have merit, there is a large variability in these signs from cow to cow. For example, research has shown that pelvic ligament relaxation can start as early as 15 days, and as late as 7 hours prior to calving (Berglund et al., 1987). Due to this variability, making management decisions, such as when to move close-up dry cows to calving pens, and how often to monitor these cows can be difficult. To make matters worse, research has shown that moving cows that have already initiated calving can result in a 2.5-fold increase in stillbirths (Carrier et al., 2006).
In with the new...
A research study conducted by Schirmann and coworkers at the University of British Columbia found that rumination and feeding time are strong indicators of an imminent calving event. Eleven mature close-up dry cows were fitted with rumination collars and housed in a free stall barn equipped with a feeding system that measures individual intakes and feeding times. Additionally, cows were monitored with video cameras to determine the time of calving. Because rumination has a very specific sound, rumination collars are equipped with a microphone to record the sound of cud chewing. The feeding system utilized individual RFID tags to allow cattle access to the feed bunk, and while at the feed bunk, duration of the feeding visit and intakes were measured. Time spent ruminating dropped 15% on the day prior to calving, and this decline was further emphasized in the final 4 hours before calving. Consistent with rumination, time spent feeding also decreased considerably by 32% on the day prior to calving, and dramatically declined in the final 8 hours. Dry matter intake (DMI) also decreased by 24% on the day of calving (Figure 1). In conclusion, time spent ruminating and feeding can be monitored on farms either with rumination collars or automatic feeders, respectively to indicate an imminent calving.
These technologies emerge at a time when farm labor is becoming harder and more expensive to come by despite the fact that herd sizes continue to grow. Farmers can utilize precision dairy technologies to compensate for labor shortages while still maximizing animal performance. Now, let’s get back to 1157, isn’t it about time you checked on her again?
Virginia Cooperative Extension materials are available for public use, reprint, or citation without further permission, provided the use includes credit to the author and to Virginia Cooperative Extension, Virginia Tech, and Virginia State University.
Issued in furtherance of Cooperative Extension work, Virginia Polytechnic Institute and State University, Virginia State University, and the U.S. Department of Agriculture cooperating. Edwin J. Jones, Director, Virginia Cooperative Extension, Virginia Tech, Blacksburg; M. Ray McKinnie, Administrator, 1890 Extension Program, Virginia State University, Petersburg.
February 26, 2016