Mark McCully, Vice President of Production, Certified Angus Beef LLC
For decades, Beef Science 101 taught us to match the cow to the environment and the bull to the market – but that doesn't mean there is a conflict between cow and carcass. We know consumer demand differentiates cattle value, often resulting in at least $300/head premiums for Prime beef over Select.
Cost is always important, but the most profitable commercial cow today may not be the lowest-input cow on your place. With the spread in carcass values, you have to calculate both income and expenses to find the best cows in your herd.
The emphasis on carcass merit takes nothing away form the cow's main job, to get bred and raise a healthy calf. The fundamentals don't change.
Skeptics worry about the downfall of their cow herd should they select for marbling. It may be logical to think selecting for carcass traits causes maternal traits to suffer – our schooling implied that – but it's not true in most cases.
However, cattlemen have learned to breed around genetic antagonisms for years using expected progeny differences (EPDs). We know muscle and fertility are negatively correlated, which means if you select for ribeye without regard for other traits, conception rate could slide over time. Calving ease and yearling weight are also negatively associated. Without tools, selecting for growth would cause bigger calve at birth. Those who were breeding cattle in the 1970s and '80s, during the frame race, remember these correlations all too well.
Today, though, the genetic trend for Yearling Weight and Birth Weight in Angus bulls shows how EPDs can be used effectively to bend the curve and improve both traits at the same time (Graph 1).
Moreover, marbling, the key carcass trait for consumer demand, has no negative correlations. It has a moderate positive correlation to milk, which means you should look at both EPDs to coordinate milk with 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 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 (Graph 2).
We find herds that turn in remarkably high Certified Angus Beef® brand acceptance rates, 60% to 75% or higher, from the high desert, Gulf Coast, Midwest and everywhere else cows graze pastures and ranges. In each case, cows meet the requirements of their environment while still producing calves with superior marbling.
Here's how they do it:
1. Sire selection – Significant diversity combined with the ability sort sires, from the American Angus Association database, points out sires that can produce functional females for your environment and claves that produce a highly valuable carcass. Last summer, in the Angus Main Sire Summary, more than 50 bulls made the top 35th percentile for the combination of Weaning Weight, Scrotal Circumference, CE Maternal, Heifer Pregnancy, $W and Marbling EPDs.
2. Heifer selection – A good cowman still sorts first on conformation and structure, size (too big or small), age, health record and disposition. Adding more data sorts by sire group, dam's record, pelvic score and reproductive tract score, then adding still more data through genomic testing allows for precise decisions.
3. Culling the cow herd – Cull deeper than the open and problem cows, and remove those with the least genetic merit or ability to produce high value, high marbling calves.
At the end of the day, it's all about balanced selection, but don't read that as equal. Strategies that maximize marbling while also making improvements in all other economically relevant traits, regardless of environment, are not only plausible but a smart approach for cattlemen with their eye on the cow and the carcass ... and profit.