Find Your Most Profitable Days on Feed

By Lee-Anne Walter, Ph.D., Cattle Technical Services, Merck Animal Health

Skyrocketing feed prices. Increased cattle on feed. Limited packer capacity. Delayed cattle pick-ups. Widespread drought. These unfortunate realities cause heartburn for cattle producers. Difficult market conditions cause feedyard managers to evaluate the appropriate days on feed (DOF), while optimizing feed efficiency to maximize return.

Could feeding heavier cattle be an option?

With aggressive corn prices, producers may consider reducing DOF by placing heavier cattle. Taking advantage of the lower cost of gain in stocker or backgrounder situations can potentially reduce overall cost of gain. However, in times of drought, there are fewer stocker opportunities and cow-calf producers often wean earlier, making it tough to source heavier feeder cattle.

Forming strong relationships with backgrounders can offer more cost-effective feeding avenues during times of high feed costs. Calves that were weaned at a lighter-than-normal weight due to drought conditions have the opportunity to build frame and muscle and improve health outcomes prior to being placed on full feed.

Carcass performance trends

While it may appear optimal to decrease DOF, feeders need to ensure that they are targeting DOF from a carcass performance standpoint.

Over the past two decades, steer hot carcass weights (HCW) have increased nearly 100 pounds – from an average of 821 pounds for steers marketed in 2003 to an average of 916 pounds in 2019 (Figure 1).[1]

Figure 1

Steer Hot Carcass Weights – 2003 to 2020. Data Obtained from Five Area Weekly Weighted Direct Slaughter, Dressed Delivered, Steer Carcass Weights.

Looking at close-out weights, the Kansas State Focus on Feedlots survey reports monthly average outweights ranging from 1,222 to 1,293 pounds for steers marketed in April and September 2003, respectively. The 2019 monthly closeouts from the Kansas State Feedlot Performance Reports show 150 pounds heavier steer closeouts ranging from 1,344 pounds in March 2019 to 1,464 pounds in December 2019.[2]

Coincidentally, during the same 20-year period, cost of gain increased, tied to rising corn price and volatility. The value of fed cattle, price of feeder cattle, the availability of growth promoting technologies, cattle in weights and the proportion of cattle sold on a grid have all changed. The value of pounds sold alongside cost of gain helps determine a break-even and appropriate marketing time.

Economics of extended days on feed

Targeting appropriate days with increased ration costs requires knowledge of historical closeouts and application of credible serial slaughter research. For 15 years, researchers at Merck Animal Health have studied serial slaughter and how different days on feed affect gain and carcass composition.

As cattle grow and mature in the feedyard, composition of gain changes. Fat gain increases and protein gain decreases proportionally for each pound of weight gained. Since fat is more energetically dense than protein (primarily water), total pounds of live and hot carcass weight gain slow down as the animal matures.

It is worth noting that live gain decreases at a faster rate than carcass gain due in part to non-carcass tissues (viscera and offal) decelerating in growth earlier in the feeding period than carcass tissues.[3] Thus, carcass transfer (the proportion of live weight gain that is gained on the carcass) and the value of carcass gain are important variables to determine the ideal DOF.

Increased DOF improves quality grade but also increases risk of carcass discounts due to excess weight and/or increased yield grade. Additional DOF offers a different value structure for grid sellers versus live sellers due to carcass transfer and composition of gain.[4]

Recently, researchers completed an extensive serial slaughter trial in crossbred beef steers with the first harvest weight targeted for 600 pounds and the last harvest end point targeting close to 1,800 pounds.[5] Live gain from the first harvest to the second, 42 days later, was 4.9 pounds per day and consistently decreased across DOF to less than half of the original period ADG during days 336 to 377. However, carcass weight gain averaged 3.25 pounds per day during the first 42-day period and remained close to two pounds per day in implanted steers during the last 42-day period (days 336 to 377).

At a carcass value of $1.90, the value of the carcass gain for a steer gaining 1.8 pounds of carcass weight at the end of the feeding period is $3.42. The next question becomes: Are our daily costs lower than $3.42 at the end of the feeding period?

For many feeders over the past two years, it has been an exhausting struggle to predict and secure cattle sales and pick-ups with packers. Optimal DOF becomes three to four to six weeks longer than planned. Using serial slaughter data together with historical closeouts could help to derive an estimated carcass gain number and thus better predict future break-evens.

Implants and the feeding period

Implants are critical tools to improve cattle feed efficiency. These products have tremendous return on investment by shifting the growth curve of cattle, resulting in improved efficiency through heavier, leaner and larger framed animals.[6] Implants offer significant value for feedlot cattle, helping achieve higher average daily gains and 10% to 15% greater feed efficiency.

Implants with extended activity during the final finishing period help add carcass weight while maintaining carcass quality.

In one field study[4] , researchers compared performance of heifers fed to either 151, 165, 179 or 193 days on feed. Increasing DOF increased HCW but decreased average daily gain and gain:feed ratio as fat deposition increased. While increasing DOF increased HCW and profit potential, there was added risk of yield grade discounts.

The study also observed that implanting heifers with an extended-release implant resulted in similar final BW and HCW versus a more aggressive implant strategy. Researchers concluded that implant strategies substantially increase HCW and revenue and serve as important conduits of feed efficiency across all DOF.

Sorting for greater revenue

Finally, sorting is another strategy to maximize market value with grid-based systems.

Feedyards traditionally market cattle in batches, with entire pens entering and exiting the facility at the same time. This approach optimizes yard efficiency and maintains lot integrity but tends to ignore the genetic variability of cattle on feed. Even if animals start out at the same weight, invariably cattle grow at different rates. Often this results in an inconsistent pen and the potential for significant outliers.

As DOF increases, the length of time for pen mates to grow at different rates also increases. Serial slaughter research typically does not report within pen deviation or variation around the average of carcass weight. However, carcass quality grade and yield grade distributions are often reported. As a rough rule, percentage of yield grade four and five carcasses double every 21 days.[7] Therefore, there are advantages to sorting using frame measurements and visual appraisal to manage yield grade discounts in addition to weight.

Conclusion

Using serial slaughter data helps feedyards make informed decisions on appropriate number of DOF to match their cattle and marketing opportunities. Consult with your nutritionist to develop a feeding and implant program to meet your profitability goals.

Resources

1. U.S. Department of Agriculture Agricultural Marketing Service. https://mpr.datamart.ams.usda.gov/menu.do?path=Specie s\Cattle\Daily%20Cattle\(LM_CT100)%205%20Area%20Dail y%20Weighted%20Average%20Direct%20Slaughter%20Cattle%20-%20Negotiated. Retrieved June 8, 2021.

2. Kansas State University Focus on Feedlots. https://www.asi.k-state.edu/about/newsletters/focus-onfeedlots/monthly-reports.html. Retrieved June 8, 2021.

3. Carstens, GE, Johnson, DE, Ellenberger, MA, Tatum, KD. Physical and chemical components of the empty body during compensatory growth in beef steers. J Anim Sci. 1991;69:3251-3264.

4. Ohnoutka CA, Bondurant RG, Boyd BM, Hilscher FH, Nuttelman BL, Crawford GI, Streeter MN, Luebbe MK, MacDonald JC, Smith ZK, Johnson BJ and Erickson GE. Evaluation of coated steroidal combination implants on feedlot performance and carcass characteristics of beef heifers fed for constant of varying days on feed. Applied Anim Sci. 2021;37: 41-51.

5. Kirkpatrick, T. 2020. The effect of growth promoting implants and feeding duration on live performance and behavioral characteristics, biometric measurements, empty body composition and energy retention of serially harvested beef steers. Final Study Report. Study number MS-Revalor-XS-1-18. Merck Animal Health.

6. Guiroy PJ, Tedeschi, LO, Fox, DG, Hutcheson, JP. The effects of implant strategy on body weight of beef cattle. J Anim Sci. 2002;80:1791-1800.

7. Rathmann, RJ, Bernhard, BC, Swingle, RS, Lawrence, TE, Nicols, WT, Yates, DA, Hutcheson, JP, Streeter, MN, Brooks, JC, Miller, MF, Johnson, BJ. Effects of zilpaterol hydrochloride and days on the finishing diet on feedlot performance, carcass characteristics and tenderness in beef heifers. J Anim Sci. 2012;90:3301-3311.

Lee-Anne Walter, Ph.D., is a technical consultant in the cattle group of Merck Animal Health. She works with producers across the Plains region to help ensure profitable operations. Dr. Walter earned a Master of Science in ruminant nutrition from the University of Saskatchewan in 2009 and a Ph.D. in agriculture from West Texas A&M University in 2015.