Earlier this month I was fortunate enough to attend the Joint Annual Meetings for the American Society of Animal Scientists. One of the hot topics was the debate on cow size and management.
Over the past 3 decades the predominant measure of cow efficiency has been pounds of beef produced per beef cow. This figure has increased notably in this time. Between 1975 and 2005 carcass weights for steers and heifers have increased 144 and 194 pounds, respectively1. In attaining these heavier carcass weights, the face of the U.S. beef breeding herd has changed. Average live weights for mature cows and bulls have increased to 1,350 and 1,769 pounds, respectively, in 2005 from 1,047 and 1,340 pounds, respectively, in 19751. At the same time, cows were selected for increased milk production along with increased mature weight. This increased the average beef cow’s dry matter requirement by roughly 25%1.
The debate hinges on whether we should be adapting the environment to sustain these larger cattle, or if we should be choosing different genetic types to better conform to differing environments. Should we be choosing for cattle that are better adapted to limited resources with minimal inputs? In many instances this choice would lead to a smaller mature cow size and lowered milk production. Rising grain prices and an overall reduction in available grazing lands make sustaining today’s current production levels with the current genetic base a challenge.
How will you be dealing with the rising cost of harvested and supplemental feed? Do you have any plans to decrease the overall mature size of your cow herd?
1 A historical perspective on the influence of the beef industry on mature cow size. B. McMurry. J. Anim. Sci. Vol. 89, E-Suppl. 1. p. 161. 2011.
