“The Other Side of Preconditioning”
by Chris Reinhardt, feedlot specialist
When we discuss preconditioning, we almost universally think about pre-weaning vaccination. This is probably a mistake.
While on their dam, calves over 3 weeks old rarely get sick. The national cow herd has about 3.5% calf mortality rate, and those losses are split fairly evenly between the 1st 24 hours after birth, the 1st 3 weeks after birth, and the rest of the pre-weaning phase. So there is about 1% mortality in calves greater than 3 weeks old. About 1/3 of this loss is due to respiratory problems; the rest is spread out due to digestive problems (22%), weather (10%), lameness, predators, and other causes.
The reason for this 99% success rate, in older calves, is that calves are well-suited for the environment in which they’re living. Aside from the occasional late blizzard, calves aren’t stressed environmentally; aside from the recent drought, calves have nearly all their nutrients provided in abundance from milk and grass; and immune challenge rarely exceeds the ability of the calf to suppress the challenge.
So that begs the question: If we have so few health challenges in the wide-open world of the home ranch, why do some calves undergo such severe health challenges after weaning and shipment to the feedyard?
One answer, covered recently is stress for which the calves are not adequately or properly prepared. But another important way we can prepare calves for life off the home ranch is through proper pre-weaning nutrition.
In some production years, calves are weaned because it quits raining. And we often wean 6 weeks early but we’re already 6 weeks late, nutritionally speaking. The cows may have dried off and the calves may have been sliding sideways (or even backwards) nutritionally for weeks when we finally get them to market. Add this to multiple transitional stressors, and this is a good recipe for a compromised immune system.
To avoid this situation, keep a balanced, palatable, loose mineral near water sources to make sure calves are getting adequate trace minerals. Although creep feeding sometimes does not provide a competitive cost of gain, providing a palatable source of energy and protein will ensure that calves maintain the ability to mount an immune response when the challenge occurs, and the creep feeder can be pulled into a dry lot to ease the transition from pasture to dry lot and bunk feeding.
Once again, the rancher who can capture some of the efficiencies provided by weaning on the ranch of origin may have an advantage over those forced into “blacktop weaning”. Just be sure your marketing plan is designed to capture the full economic premiums available for value-added calves, in order to offset the added expense of preparing the calves for life off the ranch.
