Have you heard the argument that feeding cattle takes food out of the mouths of starving people? Why feed all that corn to cattle when it could go to hungry kids?
Dr. Tryon Wickersham—associate professor of animal nutrition at Texas A&M, speaking at an October 2018 Beef Sustainability media event hosted by the National Cattlemen’s Beef Association (NCBA)—acknowledged that such questions resonate with consumers.
“I think an important question that consumers want to know is how much feed we’re spending—maybe in their minds, wasting—that we could be using to feed children.”
However, Wickersham turned that heart-tugging “cattle-vs.-kids” narrative on its ear with a nutritionist’s technical focus on protein quality rather than mere volume.
“If we fed [the corn needed to finish a steer, about 1,400 lbs.] to a 3-year-old, we could meet the protein requirements of half a child per year,” he explained. This number came from calculating the low protein quality in corn compared to the amino acid needs of a growing kid.
Wickersham acknowledged that the efficiency of feeding the corn to a kid wasn’t great, “But it’s still half a child, so when we feed the steer, we’re taking the food out of the mouth of half a kid.”
However, given the protein “upcycling” ability of cattle to take low-quality proteins and turn them into high-quality, easily digestible protein in the form of beef, the efficiency equation looks a lot better.
“If we made the decision to feed [the 1,400 lbs. of corn] to a steer, that results in the productions of 117 pounds of beef protein. If you feed that to 3-year-old children, you can meet the amino acid requirements of 1.97—you can say two—kids.
“I think that’s an amazing story that no one knows,” he went on. “By upcycling the protein, you’re able to feed two children.”
“Upcycling” protein
Not all protein is created equal. Most ranchers know this as a matter of course, but it bears restating, especially when talking with consumers about the value of raising cattle and beef.
Wickersham and Emily Andreini—a Ph.D. candidate in Animal Biology from University of California, Davis who also presented at the NCBA beef sustainability event—presented the idea of protein upcycling as important in the overall beef sustainability discussion.
Protein upcycling is the process of taking low-quality, human-edible protein items (such as corn) and turning them into high-quality, human-edible protein items (such as beef). Protein quality can be scored based on a foodstuff’s digestible essential amino acids. For corn, that score is 36.8. For beef, it is 112, making the comparative protein quality of beef about three times that of corn.
There’s more to consider than just the differing protein qualities, however.
“Multiple factors need to be considered in assessing the sustainability of ruminant livestock production, such as the valuable role ruminants serve in the conversion of feeds grown on non-arable lands and byproducts into products suitable for human consumption,” wrote Andreini in her presentation’s white paper.
“Intensive systems, where ruminants are fed large quantities of potentially human-edible crops, such as cereal grains, pose a debate about the competition between livestock and humans for grains that could be consumed directly by humans.”
In addition to different protein qualities, there’s also the issue of how much human-edible proteins go into feeding cattle. For the most part, cattle consume forage and byproducts that are not available to humans. In most cow-calf operations where cattle are entirely on range, the human-edible protein that goes into the cattle’s diet is functionally nonexistent. An estimate from NCBA places corn as only 7 percent of a fed steer’s lifetime feed intake, and that is only at the end of its life.
Both Andreini and Wickersham recommended that ranchers and beef industry advocates try to shift the narrative of livestock sustainability from simply calories in versus calories out—or protein in versus protein out—to human-edible protein in versus human edible protein out. This more nuanced approach might be harder to articulate but it comes closer to calculating a real-world value.
Despite this, the protein quality line is likely easier to communicate to consumers.
“Animal proteins have greater value than plant-based proteins,” Wickersham summarized.
“It is hard for you to meet your amino acid requirements eating corn or wheat. We’d have to consume a lot of corn—and excess calories—to meet our amino acid requirements.”
Unintended side effects
When trying to meet the protein needs of Wickersham’s proverbial 3-year-old with the corn that would otherwise go to finish a steer, there would be a lot of excess calories.
The child would have to eat 2,800 lbs. of corn a year (1,400 lbs./year only met the protein needs of half a 3-year-old), or 7.67 pounds of corn a day, to reach their protein needs. A pound of corn contains about 385.6 calories. Aside from the practical problems with any human trying to eat that much corn, that would be a whopping 2,958 calories a day just from corn.
The USDA recommends 3-year-olds should get 1,000-1,400 calories per day depending on size, activity level, and sex.
By comparison, if the corn was fed to a steer and the resulting 117 lbs. of beef was fed to the two 3-year-olds whose protein needs could be met by it, that would be much more realistic. Each tot would need to consume 58.5 lbs. of beef a year, or about 2.6 oz. of beef per day.
Different cuts of beef vary considerably in their calorie counts, but using top sirloin with 650 calories per pound, the kid’s beef “cost” in calories would be about 107. If we used the calorie count for 85 percent ground beef, that calorie cost would be about 187.
Both Wickersham and Andreini pointed out the value of high-quality proteins in the human diet, especially to the cognitive development of young children. Wickersham, in his presentation’s white paper, praised the ability of cattle to “upcycle” proteins and aid in human development.
“However, as beef consumers move further from production, their understanding and appreciation for the conversion of human-inedible feedstuffs into beef is diminishing amid questions of beef’s sustainability,” he wrote.
“Clearly articulating beef’s contribution to meeting the protein needs of a growing population is imperative if beef is to remain in the center of the plate.” — Kerry Halladay, WLJ editor
