The Interplay of Frame Size and Production Efficiency
By Lauren L. Hulsman Hanna, Ph.D., Assistant Professor; Michaella A. Fevold, Student; and Robert J. Maddock, Ph.D., Associate Professor, Department of Animal Sciences, North Dakota State University
What Is the Right Size?
The beef cattle industry remains a unique set of genetically diverse breed types, where each serves a purpose within the industry. Frame size, expressed as either a calculated or subjective frame score, provides producers an understanding of lean-to-fat ratio potential in their animals. Research has shown that average harvest weight for beef cattle in the United States has increased more than 300 pounds in the past 40 years, with 100 pounds of that increase occurring in the past decade4. This provides proof of increased average frame size of beef cattle across the industry.
Large size does come with advantages, such as improved production efficiency by lessening environmental impact and maintaining pounds of beef produced (i.e., the United States has reduced the number of animals fed by 10 million over the past 40 years). With larger harvest weights comes larger carcass weights. This has benefited consumers with a decrease in ground beef prices, but often has inadvertent consequences on other cuts.
For example, research has shown that consumers are willing to eat larger ribeye steaks, but often do not realize the impact on thickness it may have to maintain specific portion sizes (e.g., a 10-ounce ribeye with larger ribeye area would need to be cut thinner). Price, Quality Grade, color and shape are other characteristics that drive consumer preference2, 3, where increasing carcass size can cause problems with maintaining these preferences.
Since the mid-2000s, research at North Dakota State University’s (NDSU) Dickinson Research Extension Center (DREC) has focused on American Aberdeen-influenced offspring compared to conventional offspring types. Carcass data on steers from the two herds (“beef” vs. “range,” where range has Aberdeen influence) at DREC has been characterized based on frame-size groups (small, medium small and medium large) for a set of steers5.
Small-framed steers (Aberdeen Angus base) produced carcasses with the same dressing percentage, 12th rib fat depth and U.S. Department of Agriculture Yield Grade compared to carcasses from medium small and medium large framed steers. While small-framed steers produced smaller ribeye steaks (13.35 square inches vs. 14.37 square inches or 15.72 square inches), they did produce the largest ribeye steak in relation to their hot carcass weights (1.03 square inches per hundredweight vs. 0.89 square inches per hundredweight or 0.9 square inches per hundredweight). This bodes well for a beef producer if consumer preference, not pounds, is the driving force of production. What if you could have both though?
The end result of any beef cattle operation is meeting consumer demands, but a cow-calf producer must also weigh consequences of size on cowherd performance. So, what kind of cows can be used to get desirable offspring?
A producer must first define what a desirable offspring is. If being sold for weaning weight value, then more pounds at weaning is desired. This can be accomplished either through bigger calves or more calves weaned. With the right crossbreeding scheme, bigger calves is not necessary. Rather, increasing the number of calves produced can be much more efficient while moderating cow size.
For example, consider two herds of cows. Herd 1 has an average cow weight of 1,100 pounds whereas Herd 2 has an average cow weight of 1,500 pounds. With a daily feed intake per cow of 16 or 20 pounds per day, respectively6, we could run 90 Herd 1 cows and would need just over 525,000 pounds of forage for a year. For that same amount of forage, we could run 72 cows with Herd 2. That’s 18 more cows in Herd 1 than Herd 2, which means 18 more potential progeny. Of course, smaller cows will produce smaller offspring.
Similar cows at DREC produced, on average, 427-pound calves (Herd 1-type cows; majority have Aberdeen Angus influence of more than one-quarter) and 500-pound calves (Herd 2-type cows; conventional-type cows). That’s a difference of 73 pounds per calf, but the additional numbers of 427-pound calves more than makes up for smaller size. Consider if 90 percent of each herd weans their calves. That is 81 cows in Herd 1 and 65 cows in Herd 2, resulting in 37,149 pounds of calf weaned for Herd 1 and 32,500 pounds of calf weaned for Herd 2 (a difference of 4,649 pounds).
As of April 30, 2019, feeder steers in North Dakota were selling at $205 per hundredweight for 425-pound average weight and $183 per hundredweight for 500-pound average weight. That’s an income of $76,156 for Herd 1 vs. $59,475 for Herd 2, or a difference of $16,681. For that extra money, you are not using any additional feed resources, which typically make up the bulk of costs and have the most environmental impact.
By crossbreeding, producers also benefit from heterosis, which means survival traits and maternal attributes of crossbred dams get a boost (i.e., improved performance) just because of improved gene combinations. Picking the right breeds is an important factor here. The American Aberdeen breed provides an opportunity to moderate frame size while maintaining desirable growth and size. Research at DREC has shown that F1 Aberdeen-cross cows average around 1,000 pounds, whereas conventional crossbred cows average around 1,300 pounds7. That is a 300-pound decrease in cow size in one generation. Even though that is a large size decrease, cows can still produce calves with desirable growth and carcass characteristics, providing an important role that the American Aberdeen Association can fill.
In summary, determining the “right” size cattle is dependent on production goals and income sources. Even so, bigger does not always mean better. Therefore, it is critical that producers consider options to maintain efficient production systems while also maximizing profit. Recent research at DREC and NDSU’s Fargo, N.D., campus also shows that even within size groups, variability exists (i.e., nutritionally efficient cows can be found in small cows1). This suggests, with the right selection tools, frame size does not dictate every trait and can be used to change the average.
Footnotes:
1Hulsman Hanna, L. L. 2017. Genetic selection for cow efficiency: what is the next step? Proceedings from 2017 World Cattlemen’s Cow Efficiency Congress, Manning, ND.
2Killinger, K. M., C. R. Calkins, W. J. Umberger, D. M. Feuz and K. M. Eskridge. 2004. Consumer visual preference and value for beef steaks differing in marbling level and color. Journal of Animal Science 82(11): 3288-3293. doi: 10.2527/2004.82113288x
3Leick, C. M., J. M. Behrends, T. B. Schmidt and M. W. Schilling. 2012. Impact of price and thickness on consumer selection of ribeye, sirloin, and top loin steaks. Meat Science 91(1): 8-13. doi: 10.1016/j.meatsci.2011.11.021
4Maples, J. G., J. L. Lusk and D. S. Peel. 2018. Unintended consequences of the quest for increased efficiency in beef cattle: when bigger isn’t better. Food Policy 74: 65-73. doi: 10.1016/j.foodpol.2017.11.005
5Maddock, R. J. 2017. Impact of production scheme and frame size on carcass traits. Proceedings from 2017 World Cattlemen’s Cow Efficiency Congress, Manning, N.D.
6Swanson, K. C. 2017. Nutritional effects of frame size on efficiency and longevity of beef cows. Proceedings from 2017 World Cattlemen’s Cow Efficiency Congress, Manning, N.D.
7Ringwall, K. A. 2017. What is right for the beef business? A discussion on cattle size. Proceedings from 2017 World Cattlemen’s Cow Efficiency Congress, Manning, N.D.