ENVIRONMENTAL CONCERNS ABOUT ANIMAL MANURE

The structure of swine production has changed dramatically in the last four decades. Raw materials for swine feeds are often grown in region s other than where swine production takes place. Swine manure is mostl y spread in the neighborhood of the facilities, which may lead to soil accumulation of minerals such as P, Cu, and Zn. Moreover, soil nitrat e may leach and result in enhanced nitrate levels in ground and surfac e water. Large swine units generate odors, ammonia, and dust that can exceed tolerable levels. Negative effects of swine production on the e nvironment have already led to new legislation that limits the use of animal manure or the expansion or localization of pig operations in so me countries. The consequences of intensive swine production on the en vironment and possible solutions by means of nutrition are outlined. A lso, discussed are experiences from the Dutch situation, forthcoming l egislation, and environmental constraints on pig production in the fut ure. Our approach centers more on the system level.