Look at the genetic trend for performance traits in commonly used beef breeds and the steep, positive slope of improvement is staggering. But if you compare that to the pounds on the ground, and the ability of commercial cows to breed, calve, and weana calf and then breed back, the lack of progress is just as shocking. "People don't want to hear it, but I can find no credible evidence suggesting the average weaning weight per calf has increased in this country for the last 10 years," says Stan Bevers, Texas AgriLife Extension agricultural economist. In fact, according to Southwest Standardized Performance Analysis (SPA), three key measures of cow productivity are declining.
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