Jason Rowntree
C.S. Mott Professor of Sustainable Agriculture Michigan State University
- East Lansing MI
Jason Rowntree’s research focus is identifying the metrics and management that reflect ecological improvement in grazing land systems.
Media
Biography
Areas of Expertise
Education
Michigan State University
Ph.D.
Mississippi State University
M.S.
Texas A&M University
B.S.
News
Cattle Production That Enhances Water and Environmental Quality
Circle of Blue online
2024-08-08
Michigan State’s Jason Rowntree is out to prove that ranching is an ecological asset.
Rowntree testifies before Senate Ag Committee in support of research, Extension funding
Michigan State University online
2022-12-12
WASHINGTON, D.C. – Michigan State University C.S. Mott Professor of Sustainable Agriculture Jason Rowntree testified before the United States Senate Committee on Agriculture, Nutrition and Forestry on Dec. 6. Rowntree discussed the key role federal funding plays in his research and Extension programs and how those programs benefit agricultural stakeholders in Michigan and across the country.
Michigan researcher imparts grazing wisdom
FarmProgress online
2019-01-14
Jason Rowntree gained part of his grazing strategies from conversations with the late Nebraska grazing expert, Terry Gompert.
Journal Articles
Challenges for the balanced attribution of livestock’s environmental impacts: the art of conveying simple messages around complex realities
Animal Frontiers2023
Meat production is often listed among the largest contributors to climate change, and is usually associated with biodiversity damage, feed-food competition, and water scarcity. This assumption is largely based on the biogenic methane (CH 4) emissions of the global herd of ruminants and its occupation of land. Environmental assessments of the livestock sector are all too frequently stated in simplistic terms, making use of a myopic selection of metrics, and overlooking underlying heterogeneity and complexities.
US manure methane emissions represent a greater contributor to implied climate warming than enteric methane emissions using the global warming potential* methodology
Frontiers in Sustainable Food Systems2023
Introduction
It is important to relate different greenhouse gas (GHG) emissions to a carbon dioxide (CO2) equivalence (CO2-e) basis. This is typically done by multiplying the emissions of a GHG by its global warming potential (GWP), usually on a 100-year basis (GWP100). For methane (CH4), the predominant GHG from livestock production, the GWP100 value is 28. The GWP100 method has been shown to not adequately relate CH4 emissions to actual climate warming due to CH4′s short atmospheric lifespan (~12 years). As such, a newer method has been developed, termed GWP*. This method relates current emission rates to previous emission rates, typically on a 20-year time horizon.
Measuring the phytochemical richness of meat: effects of grass/grain finishing systems and grapeseed extract supplementation on the fatty acid and phytochemical content of beef
Foods2023
Grass-finished beef (GFB) can provide beneficial bioactive compounds to healthy diets, including omega-3 polyunsaturated fatty acids (n-3 PUFAs), conjugated linoleic acid (CLA), and secondary bioactive compounds, such as phytochemicals. The objective of this study was to compare fatty acids (FAs), micronutrients, and phytochemicals of beef fed a biodiverse pasture (GRASS), a total mixed ration (GRAIN), or a total mixed ration with 5% grapeseed extract (GRAPE). This was a two-year study involving fifty-four Red Angus steers (n = 54). GFB contained higher levels of n-3 PUFAs, vitamin E, iron, zinc, stachydrine, hippuric acid, citric acid, and succinic acid than beef from GRAIN and GRAPE (p < 0.001 for all). No differences were observed in quantified phytochemicals between beef from GRAIN and GRAPE (p > 0.05).
Near-Infrared Spectroscopy and Chemometrics Methods to Predict the Chemical Composition of Cratylia argentea
Agronomy2023
Cratylia argentea is a leguminous shrub that has the potential for use as livestock feed in tropical areas. However, time-consuming and labor-intensive methods of chemical analysis limit the understanding of its nutritive value. Near-infrared spectroscopy (NIRS) is a low-cost technology widely used in forage crops to expedite chemical composition assessment. The objective of this study was to develop prediction models to assess the crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and dry matter (DM) of Cratylia based on NIRS and partial least squares analysis. A total of 155 samples were harvested at different maturity levels and used for model development, of which 107 were used for calibration and 48 for external validation.
Energy requirement for primiparous Holstein× Gyr crossbred dairy cows
Journal of Dairy Science2024
Our objective was to estimate the requirements of metabolizable energy (ME) and net energy for the maintenance (NEm) of lactating and dry cows, the efficiency of ME utilization for milk production (kl) and tissue gain (kg), and the use of body energy mobilization for milk production (kt) throughout the lactation of primiparous crossbred Holstein × Gyr cows, using open-circuit respiration chambers. Twenty-nine primiparous Holstein × Gyr crossbred cows with an initial BW averaging 563 ± 40.1 kg and 2.5 ± 0.09 years old were used throughout lactation and dry periods.
