Animal Science Department


Date of this Version

December 1991


Published for Proceedings, The Range Beef Cow Symposium XII December 3, 4 & 5, 1991, Fort Collins, Colorado.


For the last several years cattlemen have stressed high production, especially weaning weight in their cow calf operations. It was felt, m order to be profitable output from the cow herd must be maximized. As a result, of selection for both growth and milking ability of the cow has markedly increased weaning weights and in most herds mature cow size has also increased. Compared to 10-12 years ago, today we are producing 90-95% of the beef with 2/3 of the cows.

As we expect more from the cow, nutrient intake must also increase. In many cases producers have been able to increase both cow size and weaning weights while still utilizing the available resources on the ranch and have not had adverse affects on reproductive performance. However, in many situations we have not been able to meet the cows nutrient needs from the ranch resources and one of two things have occurred. The rancher has either had to supplement at much higher levels or the cows became thin and reproduction suffered. In both cases, this costs money and usually lowers profitability.

The challenge today is to bring our production, weaning weights, yearling weights, etc., up to the point that profitability is near maximum. Cattlemen have found that the point at which reproduction starts to fail is where we should stop trying to increase output. It has been said that reproduction is 5 times more important than growth and 10 times more important than quality, as far as their effect on profitability. Ever since ranchers had cows, it has been known that to assure a high pregnancy rate cows had to be in good body condition. Therefore cows are often fed more than necessary because many ranchers do not want to take a chance of a low pregnancy rate. In other words, it is easy to assure a high pregnancy rate -- just over feed the cow.

With today’s cost conscious ranchers, the real challenge is to feed just enough to assure optimum production and profitability, which may well mean something less than maximum production.

Feed costs account for the major portion of annual cow cost. In states where cost of production has been accurately determined it has been interesting to note the tremendous difference in how much it costs to produce a pound of weaned calf from one ranch to another. In herds in Iowa and in Nebraska Integrated Resource Management (IRM) cooperator herds, it was found that cost of reproducing a weaned calf varied $.20/lb ($.72 to $.92/lb). Although no one single factor accounted for all of the differences in cost of production, the major factor was often the cost of feed.

With a better understanding of cow body condition and the level of actual body fat that is required for good reproductive performance, we are approaching a time where we can use tools to fine tune our feeding program.