Butch Sleezer Sleezer, Inc.

Publish Date: March 25, 2010

Animal production involves the feeding and care of animals to obtain usable end products, such as meat or milk. Since the efficiency with which animals use nutrients is less than 100%, a portion of the nutrients supplied to the animal is excreted as feces. The end/byproducts of metabolism are excreted in urine. Traditionally, these excreta were used as fertilizers for crops and thus were an integral part of the nutrient cycle. Over the last decade, animal production has expanded significantly in areas without adequate local feed production. To sustain expanding animal agriculture, feed ingredients were shipped in from major crop producing regions, initiating the import of nutrients, including nitrogen and phosphorus into animal producing regions. Due to the bulk of animal manure relative to its weight, shipping it to the feed producing regions for use as a fertilizer was not economically viable. Alternative methods to deal with manure were thus sought. Some are focused on different processing and storage techniques after manure production, while others deal with reducing the excretion of nutrients in manure. This factsheet outlines some of the underlying principles for modifying pig diets with the objective of reducing nutrient excretion and ammonia and odor emissions.