Balancing production output and environmental impact in animal production.

摘要

The conversion of animal feed into useful outputs generates waste products that have substantial impacts on the environment like methane, ammonia, and nitrous oxide. In addition, the production of feeds consumes resources, such as direct energy for cultivation together with indirect energy embodied in materials like fertilizers and equipment like tractors or milking machines. It also leads to diffuse pollution from nitrate, phosphate and nitrous oxide. Life Cycle Assessment (LCA) traces the production of any defined amount of a product back to natural resources in the ground (crude oil and rock phosphate) and calculates the emissions to the environment from all processes, leading to the final products as it emerges from a pre-defined system boundary. The consumption of resources and emissions to the environment are collectively termed environmental burdens. A life cycle approach to animal production yields valuable insights into animal production. Most resources used a large promotion of emissions to the environment are associated with feed production, so highlighting the great importance of understanding (and improving) feed production and utilization by livestock. There are apparent systematic differences between ruminant and non-ruminant production that are associated with enteric methane emissions. Increasing global warming through methane emissions is the consequence. Finding robust solutions to this that do not otherwise increase environmental burdens unacceptably is a key challenge for animal science. The use of byproducts is good practice, wherein a small resource is used as long as they are available. Unbalanced use can lead to more nitrogen emissions and adverse environmental effects as a consequence.