Sustainable intensification of grazing operations using targeted supplementation

Authors: BECK, PAUL - Oklahoma State University; GRIGSBY, ZANE - Oklahoma State University; ADAMS, JORDAN - Texas A&M University; Moffet, Corey; Gunter, Stacey

Submitted to: International Rangeland Congress
Publication Type: Proceedings
Publication Acceptance Date: 6/2/2025
Publication Date: 6/2/2025
Citation: Beck, P.A., Grigsby, Z.N., Adams, J.M., Moffet, C., Gunter, S.A. 2025. Sustainable intensification of grazing operations using targeted supplementation. International Rangeland Congress. In: XII International Rangeland Congress Australia 2025, June 2-6, 2025, Adelaide, Australia. p. 1679-1682.

Interpretive Summary: Producers are under significant economic pressures to maximize production per hectare, which can prove harmful to the range condition, where desired forage species are overgrazed decline in the stand. Feeding high levels of supplemental feed based on corn co-products of the ethanol production industry can offset forage consumption by 0.50 to 0.55 kg per kg supplemented in grazing calves and lead to higher stocking rates, without reductions in forage mass and animal performance. These projects were conducted in the subhumid rangelands of western Oklahoma USA (Klemme Research Range [KLEMME]) and in humid introduced forage production system in eastern Oklahoma (Eastern Research Station [ERS]) and aimed to use targeted supplementation to increase live-weight gains of growing cattle and maximize production per hectare and to replace synthetic fertilizer at ERS. At KLEMME, calculated nitrogen use efficiency, nitrous oxide emissions, methane emissions, total carbon dioxide equivalent emissions and carbon dioxide equivalent emission intensity (kg/kg of LWG) were decreased. At ERS calculated nitrogen use efficiency, nitrous oxide emissions, total methane emissions total carbon dioxide equivalent emissions and carbon dioxide emission intensity were intermediate for HS, but carbon dioxide equivalent emission intensity was improved. Performance of steers followed through finishing on high-concentrate diets were not affected by previous supplementation treatment during grazing and increased gains pre-finishing resulted in similar carcass weights with decreased days on feed and 15% less total feed required for finishing without impacting carcass quality. Targeted supplementation has the potential to increase performance in intensified grazing systems, increase beef production per hectare, and reduce grazed forage and harvested feeds with the potential to reduce the overall environmental impact of beef production.

Technical Abstract: These projects were conducted in the subhumid (700 mm/year annual precipitation) rangelands of western Oklahoma USA (Klemme Research Range [KLEMME]) and in humid introduced forage production system in eastern Oklahoma (Eastern Research Station [ERS]). Aiming to use targeted supplementation to increase LW gains of growing cattle and maximise production per hectare and to replace synthetic fertiliser at ERS. Treatments at Klemme included: 1) Positive Control (PC)– 1 kg daily supplementation with distiller’s grains (DDGS) cubes in late summer only, or 2) High Supplement (HS) - DDGS cubes offered at 0.75% of liveweight all summer to increase stocking rate 33%. Treatments at ERS included: 1) Fertilized Control (FC) - no supplementation on N fertilized pastures (112 kg N/ha); 2) Fertilized Supplement (FS) – steers fed supplemental DDG cubes at 1.2 kg/d prorated for 3-d/wk feeding on N fertilized pastures throughout the summer; or 3) High Supplement (HS) – steers supplemented DDG cubes at 0.75% of BW/d on unfertilized pastures prorated for 5-d/wk feeding; as described by Adams et al., 2022b). The HS treatment increased stocking rates by 33% and increased LW gain/ha by 89% compared with PC at KLEMME. The HS treatment increased steer performance while replacing synthetic N inputs in FC and FS treatments. At KLEMME, calculated N use efficiency, N2O emissions, methane emissions, total CO2 equivalent emissions and CO2 equivalent emission intensity (kg/kg LWG) were decreased in HS. At ERS calculated N use efficiency, N2O emissions, total methane emissions total CO2 equivalent emissions and CO2 emission intensity were intermediate for HS, but CO2 equivalent emission intensity was improved. Performance of steers followed through finishing on high-concentrate diets were not affected by previous supplementation treatment during grazing and increased gains prefinishing resulted in similar carcass weights with decreased days on feed and 15% less total feed required for finishing without impacting carcass quality. Targeted supplementation has the potential to increase performance in intensified grazing systems, increase beef production per hectare, and reduce grazed forage and harvested feeds with the potential to reduce the overall environmental impact of beef production.