Great effort is placed on preventing and managing common illnesses that strike calves, including respiratory disease and scours. When calculating calf loss, however, many farms forget about calves that never make it to the hutch. According to Franklin Garry, Colorado State University, noninfectious ailments associated with dystocia account for one-third to two-thirds of calf losses.
By definition, dystocia is a delayed or difficult birth. The causes for dystocia are many, explained Garry, including a fetus/dam size mismatch, fetal malpresentation and maternal health issues, including illness like hypocalcemia.
Data from NAHMS has shown preweaned calf death rates between 7.8 and 10.8 percent over the past 20 years. Garry emphasized that these are the rates producers are reporting and that actual deaths may be much higher due to a group of calves that often don't get recorded: stillbirths.
A stillbirth is a calf that is delivered dead or that dies within 48 hours of birth. Some genetic mutations may impact stillbirth incidence, but they are pretty nominal. More often, a difficult birthing is to blame.
Dystocia has been found to result in stillbirths in 12.6 percent of heifers and 6.1 percent of multiparous cows. Added to the 7 to 11 percent recorded dead due to infectious diseases, that is a high number of calf losses. "We can do a lot better than that," he said.
According to 2009 USDA APHIS data, about 90 percent of stillborn calves are alive at the beginning of calving. Garry shared a few strategies that could help minimize the number of stillbirths due to dystocia at the Professional Dairy Producers of Wisconsin's Calf Connection workshop last month. They include:
- Choose sires that produce more moderately sized calves, and adopt nutritional strategies that enhance fresh cow health.
- Properly assist difficult births when needed to lessen the impact of dystocia on calves and dams.
- Identify abnormal calves, and provide more care from the start.
