Economic evaluation of grazing steers on summer annuals sod-seeded to warm-season perennial pasture

Authors: MEYER, I - University Of Arkansas; POPP, MICHAEL - University Of Arkansas; Nieman, Christine; MITCHELL, JAMES - University Of Arkansas; COFFEY, KENNETH - University Of Arkansas

Submitted to: Applied Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/9/2024
Publication Date: 12/3/2024
Citation: Meyer, I., Popp, M.P., Nieman, C.C., Mitchell, J.L., Coffey, K.P. 2024. Economic evaluation of grazing steers on summer annuals sod-seeded to warm-season perennial pasture. Applied Animal Science. https://doi.org/10.15232/aas.2024-02569.
DOI: https://doi.org/10.15232/aas.2024-02569

Interpretive Summary: Stocker cattle producers grazing primarily mixed-bermudagrass pasture typically observe low cattle performance in mid-summer and early fall. Sod-seeding warm-season annuals of greater nutritive value than bermudagrass, such as sorghum-sudangrass and cowpea, may improve summer cattle gain. However, costs of summer annual establishment are greater than perennial bermudagrass. This study compared three grazing systems; mixed bermudagrass perennial pasture, sod-seeded sorghum-sudangrass, and sod-seeded sorghum-sudangrass and cowpea for cattle performance and partial returns for each system over two years (2021-2022). Economic evaluation involved calculation of animal value gain related to grazing days, subtracting added costs of planting and financing across pasture treatments with and without summer annuals. Partial returns comparisons by year showcased that pasture improvement was too costly and especially so in 2021 when planting was delayed. Improved cattle gain on summer annuals was not able to compensate for the increased establishment costs.

Technical Abstract: In warm-season perennial pastures dominated by bermudagrass, as common in the mid-southern U.S., low ADG in stocker cattle are observed. Sod-seeding summer annuals of higher nutritive quality was thus evaluated. Unimproved bermudagrass (BG) pasture and BG improved with sorghum-sudangrass (SS) or SS-cowpeas (SSCW), were evaluated for ADG, body weight gain, and relative profit in replicated pasture trials under droughty conditions near Booneville, AR in 2021 and 2022. Higher forage quality in improved pastures documented in a companion study led to greater ADG (P < 0.0001) compared to unimproved BG pasture across study years. Higher ADG with SSCW, however, was not economically justifiable as seed expenses were $9.10 hd-1 higher for SSCW than SS. Body weight gain was impacted by grazing days as a function of weather and plant establishment of summer annuals thereby exhibiting a year × forage species interaction (P < 0.0001). Perennial BG had 91 and 95 grazing days in 2021 and 2022, while SS (SSCW) had 68(60) and 92(92) for those same years, respectively. Weather-related planting delays in 2021, led to numerically higher body weight gains with BG compared to SS and SSCW, respectively. In 2022, BG pastures required a mid-summer rest period in August, leading to SS(SSCW) body weight gains that were statistically(numerically) superior to BG. Using regression-based rather than linearly interpolated estimates of feeder cattle prices impacted profit-maximizing forage species selection. Using interpolation led to higher animal ending value estimates, in turn leading to numerically higher profit in 2022 when using SS compared to BG and SSCW. Across both years, however, higher ADG with SS was insufficient to cover added planting and seed cost (P = 0.0124) regardless of pricing method chosen. Planting summer annuals was more costly than the improvement in weight gain. Ensuring timely planting is important. Using a shorter feeder cattle period for the early grazing season with higher feed quality, and late-season cow grazing may offer opportunities for SS as a summer annual. Using a simpler linear-interpolation method may be worthwhile.