Natural pig farming is a high pig welfare, non-environmental polluting system of raising healthy, contented pigs that uses the activity of indigineous micro-organisms (IMO's) in the sty's 'living' deep bed pen flooring to rapidly decompose all pig waste. The pig raising system is designed to enable pigs to carry out core natural behavior within a healthy real world environment even though they are raised in pens.
This site provides information on the natural pig farming philosophy and practice, and highlights the benefits of the systems over the 'modern' welfare- deficient factory farming model of raising pigs.