Fiber in swine nutrition

This chapter summarizes current knowledge about dietary fiber in terms of characterization, analysis, and fermentation of fiber. It discusses postabsorptive metabolism of absorbed end products resulting from fiber fermentation in pigs and the impact of dietary fiber on digestibility and absorption of other nutrients. Based on functional, chemical, and physical properties, total dietary fiber may be divided into soluble dietary fiber and insoluble dietary fibers. Nonstarch polysaccharides are composed of up to several hundred thousand monosaccharide units. The use of high fiber ingredients in pig diets has increased to reduce feed cost in diet formulation, but increased concentration of fiber in the diet may reduce digestibility of other nutrients. A major impact of dietary fiber on nitrogen excretion in pigs is the shift of nitrogen excretion from the urine to the feces, which results in a reduction of the ratio between urine nitrogen excretion and fecal nitrogen excretion.