Commercial Agriculture Program
Fall 2009
You Can’t Manage What You Don’t Measure...Evaluating Herd Productivity and Calf Performance
By Dr. Bob Weaber, Animal Breeding and Genetics Specialist
Weaning time is a great opportunity to evaluate the productivity of your cowherd and each cow in it. Herd level measurements are computed using actual performance data.
A common measure of cow-calf herd productivity is the weaning weight per cow exposed. Simply take the sum of all calf weaning weights and divide by the number of cows you exposed to bulls during the 2008 breeding season plus the number of purchased pregnant cows or bred-heifers. This measure takes into account conception rate, calf survival at birth, calf survival to weaning, and calf weights.
For herd level evaluation, you do not need individual calf weights; draft weights of all the calves will work fine. Other useful measures that will point out management strengths or areas for improvement, include conception rate of cows exposed, calf survival rate (at birth and weaning, as a percentage of cows calving), and percent calf crop weaned.
Mature cow weights adjusted for body condition score can provide valuable information to producers for allocation of supplemental nutrition or forage allocation in management intensive grazing systems.
Individual calves and their dams may be evaluated for maternal and growth performance using adjusted weaning weights. To compute an adjusted 205-day or weaning weight you’ll need individual calf birth dates, weaning weights, and each calf’s dam’s age in addition to the weaning date. Both age-of-dam and age-of-calf contribute considerable variation to calf weaning weight.
To make fair comparisons among calves and dams, you’ll want to adjust these factors out using the adjusted weaning weight formula. The resulting adjusted 205- day weights are a reflection of the genetics of the calf for growth, the maternal ability of its dam, and the management and nutritional environment in which the calf was raised. While not a pure measure of genetic merit, adjusted weaning weights do give a general indication of the performance of a calf and its dam relative to herd mates.
A handy computer spreadsheet is available to compute adjusted weights and ratios using the Beef Improvement Federation guidelines. You can download the "Adjusted Birth, Weaning and Yearling Weight" spreadsheet at: http://agebb.missouri.edu/commag/beef/downloads.htm. Visit the Beef Improvement Federation Guidelines for more instructions on computing adjusted weaning weights and herd performance evaluation: http://www.beefimprovement.org/library/06guidelines.pdf.
Once you’ve evaluated the performance of your cattle consider bridging to an economic analysis. A useful benchmark measure of economic performance is breakeven price, which is reported in dollars per hundred weight. Breakeven price is the point where profit or losses begin. It is a function of all fixed and variable production costs divided by the total number of hundred weights of calf you produced. More sophisticated farm/ ranch level economic performance maybe computed, but that’s a topic for another day.
For more information on evaluating herd productivity and calf performance, contact Dr. Bob Weaber at 573 882-5479 or weaberr@missouri.edu.