|Hales Paxton, Kristin|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 2/15/2014
Publication Date: 4/2/2014
Citation: Cole, N.A., Todd, R.W., Waldrip, H., Hales Paxton, K.E. 2014. Greenhouse gas emissions from cattle systems: factors affecting emissions and mitigation strategies. Alberta Institute of Agrologists Annual Conference, April 1-3,2014, Banff, Canada. 1;6636.
Technical Abstract: Cattle evolved on a diet consisting primarily of forages. Thus, it is often assumed that the “ideal” system for producing cattle is pasture-based. In contrast to much of the world, beef cattle in North American typically spend a portion of their life in feedlots where they are fed diets high in grains and/or by-products. Feeding cattle nutritionally balanced, high-energy diets in confinement has many advantages over pastoral systems. However, feeding cattle in confinement leads to a concentration of nutrients into a small geographic area. Significant environmental and economic concerns include accumulation of nutrients, extraneous losses of nutrients to ground and surface water, removal of accumulated manure, excretion of pathogens and physiologically active compounds (PAC), and emissions of ammonia, greenhouse gases (GHG), odors, and dust. Nutrition and management practices influence the quantity of nutrients excreted by the animal, transformations and movements of those nutrients, as well as losses of ammonia and GHG. Fortunately, ruminants can readily utilize a variety of high-fiber by-products to produce high-quality protein. The growth of the grain-based bio-fuel and corn sweetener industries has provided cattle feeders with a large supply of by-products (distiller’s grains, corn gluten feed, etc.) that can be substituted for feed grains. Because these byproducts are usually high in fiber, N, P, and S, when fed at high dietary concentrations, manure production, N, P, and S excretion, enteric methane emissions, and ammonia, and nitrous oxide emissions from manure are all increased. However, feeding lower concentrations (< 30% of DM) of these by-products and use of grain processing techniques such as steam flaking may actually decrease the environmental footprint of feedlots by decreasing the quantity of feed grains required.