As the beef industry counters shrinking cattle numbers  with more pounds per animal, the all-important question is: How much bigger and heavier can fed cattle get? At what point does it become physiologically impossible or economically impractical to do this?
The trend to heavier carcasses has been going on for the industry’s entire history, but especially since 1975 when U.S. cattle numbers peaked at 132 million head. The industry produced just under 24 billion lbs. of beef that year. Beef production in 2002 was a record 27.2 billion lbs., yet the national herd had shrunk to 96.7 million head.
Such gains, along with huge improvements in red meat yields, are why the U.S. has the highest productivity per animal among the world’s top beef-producing nations. The U.S. in 2010 produced 761 lbs./head on a carcass-weight equivalent, followed by Canada at 747 lbs./head, the EU-27 at 606 lbs., and Brazil at 498 lbs./animal. Little wonder cattle producers from other countries want to use more U.S. genetics and cattle-raising and feeding knowledge.
When I started writing about the industry in 1986, I asked fed beef processors to describe their ideal carcass size. Their reply was 650-800 lbs. Several notable milestones have occurred since then, as weights have increased almost every year.
First, the lightest weight carcasses, notably of heifers, disappeared. Second, packers no longer discount the heaviest carcasses as they used to. The days of weight breaks at 900 lbs. and 950 lbs. are over because packers also need more pounds per animal as cattle supplies shrink.
Fast forward to current weights, which are likely to soon set new all-time records. Steer carcasses might already have done so by the time you read this. The latest weight data indicates steer carcasses averaged 867 lbs. in the week ended Aug. 25. This was 22 lbs. higher than the same week last year, and just 3 lbs. off the record set the week of Oct. 10, 2009. Meanwhile, heifers averaged 791 lbs., up 13 lbs. from last year and 15 lbs. off the record set the same week in 2009. Overall carcass weights averaged 793 lbs., up 19 lbs. from last year and 8 lbs. off the record set the week of Oct. 3, 2009.
The year-on-year increase in carcass weights is one reason why cattle slaughter remains below last year. The 19 lbs. was the equivalent of adding 19,000 head to the kill that week vs. last year. The added weight means that while cattle slaughter for the year to Sept. 1 was down 4.1% or 944,000 head, total beef production to that date was down only 2.1%, or 362 million lbs.
The big year-on-year increase in steer and heifer weights is attributable to several factors:
- Cattle feeding conditions were ideal last winter and spring, and cattle seemed unhurt by the intense heat this summer.
- Cattle feeders are feeding to heavier weights, and selling more on a carcass basis, to offset higher feed costs.
- They are also extensively using two beta-agonists that add from 17-33 lbs., on average, to hot carcass weights.
With 90% or more of steers and heifers on these feed supplements, the question is: Can they be used even more aggressively without detrimental effects on carcass quality, or has their use maxed out? If the latter is the case, the industry will have to find other ways to increase productivity.
Heavier carcasses and larger cut sizes  in the past caused retailers and foodservice users to complain about ribeyes being too large and boxes being too heavy. Such complaints have disappeared, as end users find ways to create new cuts. Like the rest of the industry, they need all the beef they can get to run their businesses profitably.