Every story has a number: 35th
I fondly remember the first beef production classes I took in college and the fundamental ideas that were impressed upon me as an ambitious but incredibly naïve student.
One that I recall most vividly is the concept of matching the cow to the environment and the bull to the market. It always made sense to me and is rooted in truth—but at some level came the idea that a conflict must exist between the cow and the carcass.
Those lectures were more than 20 years ago, but I suspect they haven’t changed much in today’s classrooms.
Skeptics worry about the downfall of their cowherd should they select for marbling
But I disagree (and have science to back up that opinion).
Muscle and fertility are negatively correlated, which simply means if you select for ribeye without regard for other traits, conception rates could slide over time.
But cattlemen have learned to breed around genetic antagonisms for years using expected progeny differences (EPDs). Calving ease and yearling weight are also negatively associated. Without tools, select for more growth and you get bigger calves at birth. Those who were breeding cattle in the 1970s and ’80s during the “frame race” remember these correlations all too well.
Today the genetic trend for Yearling Weight and Birth Weight in Angus bulls shows how EPDs can be used effectively to “bend the curve” and make progress on both at the same time.
The key carcass trait for consumer demand, marbling, has no negative correlations. And it’s moderate positive correlation to milk simply means you should look at both EPDs to match milk to your environment while your cows provide marbling in calves that meet consumer demand.
Scientists at Virginia Tech did an extensive review of published research and concluded, “…selection for improvements in marbling should not extensive review of published negatively impact scrotal circumference, age at puberty, heifer pregnancy, calving interval, or mature weight.” They also found a favorable relationship between marbling and birth weight, calving ease and $W, and in fact the genetic trends for Angus $W and Marbling are very similar.
I’ve met ranchers from every region of the U.S. who are hitting remarkably high CAB® brand acceptance rates, 60% to 75% or higher. In each case, cows meet the requirements of their environment while still producing calves with superior marbling.
Those ranchers do that through sire selection, heifer selection and cowherd culling.
And that brings us to today’s number: 35th. In the Angus Main Sire Summary last summer, more than 50 bulls made the top 35th percentile for the combination of Weaning Weight, Scrotal Circumference, CE Maternal, Heifer Pregnancy, $W and Marbling EPD. Talk about significant diversity and power in the American Angus Association database. (And talk about proof that you can have a herd that does it all.)
Just remember, at the end of the day, it’s all about balanced selection, but don’t read that as “equal.”
-Mark
Mark McCully is our vice president of production. Working from Wooster, Ohio, he enjoys analyzing data and consuming ribeyes.
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Have you been following along all month? If not, check back on all these numbers. Each one has a story:
Day one: $6.93
Day two: 2.5 million
Day three: $204.10
Day four: 12.1 million
Day five: 11/13
Day six: 8 million
Day seven: 139
Day eight: $39
Day nine: 30.1%
Day 10: 120 million
Day 11: -2.26
Day 12: 12 to 15 minutes
Day 13: 30%
Day 14: 32 million
Day 15: $154,000
Day 16: 118
Day 17: .51
Day 18: 105
Day 19: 1650
Day 20: 36,575
Day 21: 603
Day 22: 23%
Day 23: 31
Day 24: .53
Day 25: 40%
Day 26: $4.52
Day 27: 7 hours
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