Submitted to: Encyclopedia of Animal Science
Publication Type: Book / Chapter
Publication Acceptance Date: September 26, 2009
Publication Date: N/A
Interpretive Summary: Animal manure provides essential and secondary nutrients for crop and pasture production. It also increases soil organic matter levels, enhances soil physical and biological properties, and overall soil quality. Manure also contains energy that can be converted into fuel. This article is one of nearly 300 entries in The Encyclopedia of Animal Science, which is considered a key reference for policy makers, governmental bodies, private and public research professionals, agricultural producers, students, and the public. It is intended to be a ready source of current information covering a broad spectrum of topics related to the biology, production, and uses of animals and their products in a complex, diverse, and rapidly changing world.
Technical Abstract: Manure benefits crop production through its fertilizer value and enhancement of soil physical and biological properties and overall soil quality. The fertilizer nitrogen (N) value of manure depends on the conservation of urine N. Approximately 25-35% of the N contained in manure of ruminant livestock (beef and dairy cattle, sheep) is available to the plant the season following application vs. 50-60% for poultry and swine. As livestock and crop production become more specialized, it becomes more difficult to conserve manure nutrients and recycle them through crops. Manure N losses via ammonia volatilization, nitrate leaching, and denitrification, and manure phosphorus (P) losses in runoff are the principal pollution concerns. The economics of practices that enhance manure's fertilizer value, and capture of methane during manure storage may become increasingly attractive in the current era of high fertilizer and energy costs.