A Reminder About Twin Heifers
Just a reminder about the need to give our twin heifer calves a little special attention.
Recent work involving 11,470 calves from 5 California dairies followed calves from birth through weaning. When considering calves that died (mortality) the overall mortality rates varied from 1.1 percent to 7.2 percent.
Specifically, twin heifer calves were found to have a 1.7 times greater risk of dying compared to singleton calves. These findings were similar to previous studies as well.
What is a manager to do?
1. Identify twin calves - if the calf care workers do not see the calves born have the maternity workers mark twins (for example, using a paint stick place a "T" on the calves' forehead).
2. Place a reminder on the housing for twins (for example, a cow leg band) - make it easy to remember that these calves need to have a little extra attention especially during the first month of life.
3. As weaning approaches provide the opportunity for an extra week or two of the milk ration for twins if they are significantly smaller that other calves the same age. Delaying moving into transition calf pens may provide them an opportunity to compete for feed and space with less risk of pneumonia.
Reference: Dubrovsky, S.A. and Others "Bovine respiratory (BRD) cause-specific and overall mortality in preweaned calves on California dairies: The BRD 10K Study." Journal of Dairy Science 102:7620-7328 August 2019.