Jameson R Brennan
A5089813553- Ruminant Nutrition and Digestive Physiology
- Rangeland and Wildlife Management
- Effects of Environmental Stressors on Livestock
- Genetic and phenotypic traits in livestock
- Soil Carbon and Nitrogen Dynamics
- Rangeland Management and Livestock Ecology
- Soil and Water Nutrient Dynamics
- Soil Mechanics and Vehicle Dynamics
- Wildlife Ecology and Conservation
- Agriculture Sustainability and Environmental Impact
- Animal Behavior and Welfare Studies
- Agriculture and Farm Safety
- Soil and Unsaturated Flow
- Diverse Educational Innovations Studies
- Species Distribution and Climate Change
- Parasitic Infections and Diagnostics
- Pasture and Agricultural Systems
- Helminth infection and control
- Soil Management and Crop Yield
- Yersinia bacterium, plague, ectoparasites research
- Reproductive Physiology in Livestock
- Artificial Intelligence and Decision Support Systems
- Clay minerals and soil interactions
- Time Series Analysis and Forecasting
- Crop Yield and Soil Fertility
South Dakota State University
2016-2025
Brookhaven National Laboratory
1988
Soil organic carbon (SOC) is closely tied to soil health. However, additional biological indicators may also provide insight about C dynamics and microbial activity. We used SOC the other (potential mineralization, permanganate oxidizable C, water extractable β-glucosidase enzyme activity) from North American Project Evaluate Health Measurements examine continental-scale drivers of these indicators, relationships among effects health practices on indicator values. All had greater values at...
Aggregate stability is a commonly used indicator of soil health because improvements in aggregate are related to reduced erodibility and improved soil–water dynamics. During the past 80 90 years, numerous methods have been developed assess stability. Limited comparisons among resulted varied magnitudes response management practices influences inherent properties climate. It not clear whether selection specific method creates any advantage investigator. This study assessed four measuring...
Abstract Currently accepted pedotransfer functions show negligible effect of management‐induced changes to soil organic carbon (SOC) on plant available water holding capacity (θ AWHC ), while some studies the ability substantially increase θ through management. The Soil Health Institute's North America Project Evaluate Measurements measured content at field using intact cores across 124 long‐term research sites that contained increases in SOC as a result management treatments such reduced...
Abstract Farmers, scientists, and other soil health stakeholders require interpretable indicators of hydraulic function. Determining which to use has been difficult because measurement disconformity, spatial temporal variability, recently established treatments, the effect site characteristics on management practice differences. The North American Project Evaluate Soil Health Measurements includes 124 sites uniformly sampled across a range practices in America 2019. We compare recommend...
Potential carbon mineralization (Cmin) is a commonly used indicator of soil health, with greater Cmin values interpreted as healthier soil. While are typically in agricultural soils managed minimal physical disturbance, the mechanisms driving increases remain poorly understood. This study assessed bacterial and archaeal community structure potential microbial drivers maintained under various degrees disturbance. mineralization, 16S rRNA sequences, characterization data were collected part...
Abstract Various soil health indicators that measure a chemically defined fraction of nitrogen (N) or process related to N cycling have been proposed quantify the potential supply crops, key function. We evaluated five (total N, autoclavable citrate extractable water‐extractable organic potentially mineralizable and ‐acetyl‐β‐ D ‐glucosaminidase activity) at 124 sites with long‐term experiments across North America evaluating variety managements. found 59%–81% variation in was among sites,...
Virtual fence (VF) is the use of a global positioning system (GPS) to dictate where on landscape livestock can graze without relying traditional physical such as barbed wire. The recent acceleration in development and adoption VF technology for grazing management has been characterized by evolution divergent terminology. Different research commercial entities have adopted terms definitions independently. Some are inherently problematic, while others more aligned, simple fact that differences...
Abstract Stocker cattle can be managed in many grazing environments (variable range health, forage quality and quantity), which could impact subsequent performance carcass attributes. The objective of this research was to determine the influence vegetative composition diversity driven by history during stocker phase on traits economic returns beef steers. Yearling steers (n = 134, 116, 131, 2020, 2021, 2022, respectively) were assigned randomly pastures that had been at three levels stocking...
Rangelands are the dominant land use across a broad swath of central North America where they span wide gradient, from <350 to >900 mm, in mean annual precipitation. Substantial efforts have examined temporal and spatial variation aboveground net primary production (ANPP) precipitation (PPT) this gradient. In contrast, secondary productivity (NSP, e.g., consumer production) has not been evaluated analogously. However, livestock production, which is form NSP or supported by non-cultivated an...
Advancements in technology have ushered a new era of sensor-based measurement and management livestock production systems. These technologies the ability to automatically monitor feeding, growth, enteric emissions for individual animals across confined extensive One challenge with is large amount data generated, which can be difficult access, process, visualize, information real time ensure equipment working properly are utilizing it correctly. A solution this problem development application...
Abstract Advancements in precision livestock technology have resulted an unprecedented amount of data being collected on individual animals. Throughout the analysis chain, many bottlenecks occur, including processing raw sensor data, integrating multiple streams information, incorporating into animal growth and nutrition models, developing decision support tools for producers, training science students as scientists. To realize promise management technologies, open-source tutorials must be...
Several quantitative diagnostic techniques are available to estimate gastrointestinal parasite counts in the feces of ruminants. Comparing egg and oocyst magnitudes naturally infected samples has been a recommended approach rank fecal techniques. In this study, we compared Mini-FLOTAC (sensitivity 5 eggs per gram (EPG)/oocysts (OPG)) different averaged replicates modified McMaster 33.33 EPG/OPG) 387 from 10 herds North American bison Central Great Plains region USA. Both were performed with...
Current water footprint assessment methods make a meaningful of livestock consumption difficult as they are mainly static, thus poorly adaptable to understanding future and requirements. They lack the integration fundamental ruminant nutrition growth equations within dynamic context that accounts for short- long-term behaviour time delays associated with economically significant beef-producing areas. The current study utilised System Dynamics methodology conceptualise beef cattle mechanistic...
Abstract. Black-tailed prairie dogs (Cynomys ludovicianus) have been described as a keystone species and are important for grassland conservation, yet many concerns exist over the impact of on plant biomass production consequently livestock production. The ability to map communities in pastures colonized by can provide land managers with an opportunity optimize rangeland while balancing conservation goals. aim this study was test random forest (RF) models classify five located off dog towns...
Abstract The objectives were to determine if previously classified, efficient (LRFI, low-residual-feed intake, n = 12 × 2 yr) vs. inefficient (HRFI, high-residual-feed lactating 2-yr-old Hereford Angus cows differed in grazing behavior, body weight (BW), condition score (BCS), and calf weaning while rugged rangeland pastures. Cows fitted with halters containing both an accelerometer a global positioning system (GPS) data logger during June 14 July 4, 2016, August 25, May 23 12, 2017, 5 28,...
One objective of the ongoing “Renewal on Standing Rock Reservation” project is to evaluate response grazing steers level prairie dog colonization Northern Mixed Grass Prairie. We fenced four pastures create an increasing gradient a proportion pasture area colonized by dogs. Pastures are stocked with yearling during each growing season. Comparing steer performance, Global Positioning System (GPS) locations grazing, diet samples, and ingestive behavior at colony per allows prediction optimal...
The objective was to determine if low- or high-residual feed intake (LRFI HRFI, n = 24 for each) Hereford × Angus cows on continuously rotationally grazed rangeland altered their grazing behavior when provided a protein supplement in late autumn. Treatments included grazed, control (CCON, 12); supplemented (CTRT, (RCON, and pastures (RTRT, 12). Cows each treatment had time (GT), resting (RT), walking (WLK) measured 2 years with accelerometers. Bite rate (BR) also measured. Time distributions...
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