With the drought last summer and fall, we were set up for a difficult breeding season for spring-calving cows this year. In most of our service area, cows actually gave up some body condition during the 1997 growing season because forage quality and quantity were suffering. Hay production was down.
The usual upturn in forage production in late August and September didn't materialize because the rains didn't come. In fact, many producers began feeding hay in late summer, which put downward pressure on already limited hay supplies. In general, cows in this area went into the winter with less body condition than I've seen in a long time. Additionally, some producers have tried to stretch marginal hay supplies, often at the cows' expense.
Fortunately, this winter has been relatively mild so far. At this writing in early February, it is 60 degrees outside. Winter annuals and even clovers are actively growing; trees are budding out. As a result, cows have used less of what they've eaten to keep warm, leaving more for holding and even adding body condition.
At this point in the winter, most cows have as much as or more body condition than they did going into last fall. Maybe we will escape hard weather from now on, and cows will continue to increase in condition up to calving; then hold their own afterwards until green grass comes. If February and March are mean, however, there will be many females facing increased calving difficulty, slower return to estrus after calving, and reduced conception rates because of inadequate body condition.
If your females have too much body condition to make up before the breeding season, there are some practices you may want to consider.
"Flushing" is simply giving a female adequate feed so that she is in a positive gain mode prior to breeding. For beef cattle, conception is a "luxury" they allow themselves only when their plane of nutrition will support a pregnancy.
A cow won't rebreed until she has adequate nutrition above what she needs for maintenance and milk production. Flushing is providing that level of nutrition. It can be accomplished with feed, high quality hay, or small grain pasture. By itself, flushing thin cows before the breeding season can help improve conception rates.
The effectiveness of flushing can be increased, however, when the calves are removed from the cows for 48 hours or so. As calves nurse, the hormones that bring on estrus are lessened. Removing the calves for a short period of time allows those hormones to begin flowing so that more cows are cycling when the breeding season starts. Calf removal is most effective just before the bulls are turned out. Flushing should begin soon after calving.
A "last resort" means of getting thin cows or heifers to breed on time is to early wean their calves at around 6-8 weeks of age. Lactation uses a tremendous amount of nutrients, which means there is less to use for rebreeding and gaining condition.
Weaning the calves before the breeding season starts eliminates the need to produce milk. In all of OSU's trials with this practice, conception rate was dramatically improved. Additionally, early weaned calves weighed significantly more than suckled calves at normal weaning age. It would take plenty of preparation and planning, but may be an option for some folks this spring.
The most economically important factors to a cow/calf producer are getting the cow bred, getting her calf on the ground and raised to weaning. That's why we're in the business. And it all starts with conception. Do what ever you need to do now to ensure a high conception rate this summer. If you need any more information on these or other practices, call one of our livestock specialists.