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Grazing winter cereal pasture with stocker cattle is a common production practice on water‐limited cropland acres in the southern Great Plains. Soil erosion and loss of soil water holding capacity from interactions with tillage operations, wind, and rainfall are common problems with these systems. Despite the environmental and economic benefits reported for no‐till (NT) techniques, clean‐till (CT) establishment remains a common practice in the region. The objectives were to determine the effects of tillage system (CT and NT) on measures of animal performance and net returns, and to determine the sensitivity of net returns to the prices of glyphosate, labor, and fuel. Data representing average daily gain (ADG), steer grazing days (SGD) (ha−1), and total gain (TG) (ha−1) were obtained from a 4‐year (2010–2013) grazing trial conducted in south‐central Oklahoma. Enterprise budgeting was used to determine average revenues, costs, and net returns for each establishment system. Mixed model regression results indicated that SGD ha−1 was 11.1 greater (p < 0.0001) for CT compared to NT but ADG was 0.025 kg day−1 greater (p < 0.0001) for the NT system. The CT system realized a TG of 6.63 kg ha−1 greater (p < 0.0001) than NT. Conversely, the NT system realized a total cost of US$1067.27 ha−1, which was $105.29 ha−1 lower than the cost of the CT system. On average, the NT system realized a $67.63 ha−1 greater net return than CT. The NT system remained the most profitable even with substantial changes in prices of glyphosate, machinery labor, and fuel. Core Ideas: No‐till establishment has been shown to be economical compared to clean‐till.Despite being economical, adoption of no‐till continues to lag expectations.Animal performance and production data were produced in a scientific grazing trial.Results suggest that no‐tilling is US$68 ha−1 more profitable than clean‐till establishment.Relative profitability of no‐till was not overly sensitive to changes in prices of glyphosate, labor, and fuel. [ABSTRACT FROM AUTHOR]

Current dogma suggests increased dietary roughage may improve calf health at the expense of performance during receiving. In experiment 1, the effects of increasing dietary roughage on performance and clinical health of high-risk heifers was evaluated over a 56-d receiving period. Heifers (n  = 589; initial body weight; BW  = 230 ± 33 kg) were sourced from Oklahoma livestock auctions from April through October of 2019. Heifers were randomly assigned to pens, which were randomly assigned to 1 of 3 experimental dietary treatments in a randomized complete block design. Diets contained either: 1) 15% roughage (R15), 2) 30% roughage (R30), or 3) 45% roughage (R45) in the form of prairie hay. Orthogonal contrasts were used to test for linear and quadratic responses among experimental treatments. There was a linear decrease in overall average daily gain (ADG ; P  ≤ 0.0001) with increasing roughage inclusion which resulted in a linear decrease (P  ≤ 0.0001) in heifer final BW. A linear increase (P  ≤ 0.01) was observed for overall dry matter intake (DMI), and overall gain:feed (G:F) decreased linearly (P  ≤ 0.0001) as dietary roughage concentration increased. A quadratic response to decreasing roughage was observed (P  = 0.02) for the percent of calves treated three times for bovine respiratory disease (BRD). No other responses (P  ≥ 0.11) were detected in animal health variables. In experiment 2, Angus steers (n  = 12) and heifers (n  = 6; BW = 272 ± 28 kg) were acquired from a single ranch in Oklahoma to evaluate the same experimental dietary treatments on serum metabolite concentrations. Animals were randomly assigned to experimental treatments, with animal serving as the experimental unit in experiment 2. Statistical models for serum metabolites in experiment 2 were analyzed using repeated measures with the effects of treatment, time, and treatment × time. In experiment 2, there were tendencies for treatment × time interactions for blood urea nitrogen (BUN ; P  = 0.07) and nonesterified fatty acid (NEFA ; P  = 0.06) concentrations. No metabolites were affected by treatment (P  ≥ 0.11), while all metabolites were impacted by time (P  ≤ 0.02). In summary, growth performance was improved in calves as dietary roughage concentration decreased with minimal impacts on health and serum metabolites. These results suggest that diets containing as little as 15% roughage can be used during receiving to improve calf performance without compromising calf health when fibrous byproducts are included in the diet. [ABSTRACT FROM AUTHOR]

Spring (SPRING) and fall (FALL) born steers (n = 211) were used in a mixed effects model to evaluate calving season and conception method [artificial insemination (AI) or natural service (NS)] on finishing performance and carcass traits. SPRING were weaned in October, grazed dormant range for 90 days and grazed wheat pasture for 90 days before shipping to finish. FALL were weaned in May, and grazed tallgrass prairie for 120 days before shipping to finish. Initial and final BW, days on feed, ADG, DMI, and gain to feed efficiency were evaluated as performance measures. Dry matter intake and gain:feed were analyzed on pen basis. Hot carcass weight, yield grade, fat thickness, ribeye area, and marbling score were collected at harvest. Bodyweight of SPRING and AI steers were heavier (P ≤ 0.05) entering and leaving the feedlot than FALL and NS steers, respectively. Compared to FALL steers, ADG (P < 0.01) and DMI (P = 0.03) were greater for SPRING and required less days on feed (P ≤ 0.05). Calving season and conception method (P ≥ 0.2) did not affect gain:feed. Conception method (P = 0.5) did not affect ADG, DMI, and days on feed. SPRING had higher yield grades (P < 0.01) and increased in fat thickness (P = 0.01) compared to FALL steers. There were no differences (P = 0.2) in hot carcass weight, ribeye area, and marbling score due to season of birth. Steers born from AI mating had greater hot carcass weight (P = 0.01) and marbling score (P = 0.02), but conception method did not affect yield grade, fat thickness, and ribeye area (P > 0.2). These results demonstrate SPRING steers are heavier entering and leaving the feedlot, have higher ADG and DMI, and require less days on feed; however, gain:feed, hot carcass weight, ribeye area, and marbling score did not differ from FALL steers. An economic analysis is needed to validate an AI program based on calving season in north-central Oklahoma. [ABSTRACT FROM AUTHOR]

Intensification, the process of intensifying land management to enhance agricultural goods, results in "intensive" pastures that are planted with productive grasses and fertilized. These intensive pastures provide essential ecosystem services, including forage production for livestock. Understanding the synergies and tradeoffs of pasture intensification on the delivery of services across climatic regions is crucial to shape policies and incentives for better management of natural resources. Here, we investigated how grassland intensification affects key components of provisioning (forage productivity and quality), supporting (plant diversity) and regulating services (CO 2 and CH 4 fluxes) by comparing these services between intensive versus extensive pastures in subtropical and temperate pastures in the USDA Long-term Agroecosystem Research (LTAR) Network sites in Florida and Oklahoma, USA over multiple years. Our results suggest that grassland intensification led to a decrease in measured supporting and regulating services, but increased forage productivity in temperate pastures and forage digestibility in subtropical pastures. Intensification decreased the net CO 2 sink of subtropical pastures while it did not affect the sink capacity of temperate pastures; and it also increased environmental CH 4 emissions from subtropical pastures and reduced CH 4 uptake in temperate pastures. Intensification enhanced the global warming potential associated with C fluxes of pastures in both ecoregions. Our study demonstrates that comparisons of agroecosystems in contrasting ecoregions can reveal important drivers of ecosystem services and general or region-specific opportunities and solutions to maintaining agricultural production and reducing environmental footprints. Further LTAR network-scale comparisons of multiple ecosystem services across croplands and grazinglands intensively vs extensively managed are warranted to inform the sustainable intensification of agriculture within US and beyond. Our results highlight that achieving both food security and environmental stewardship will involve the conservation of less intensively managed pastures while adopting sustainable strategies in intensively managed pastures. • Intensification did not increase forage productivity in subtropical pastures. • Intensification increased forage productivity in temperate pastures. • Intensification reduced supporting and regulating services in pastures. • Intensification reduced CO 2 sink capacity and increased CH 4 emissions of subtropical pastures. • Intensification increased the global warming potential associated with C fluxes in pastures. [ABSTRACT FROM AUTHOR]