Comparative Dietary Fiber Definition and Methodology and Effects of Dietary Fiber in Dogs and Cats: a Review

Dietary fiber (DF) is a diverse group of compounds; all indigestible by mammalian enzymes. The definition of DF has evolved with developments in its quantification methodology, with divergence of ruminant and human nutrition, given different digestive physiology. The history of both DF's definition and quantification methodology in ruminants and non-ruminants are reviewed, providing insight into DF's role in nutrition of dogs and cats, as species for which no dietary requirement for fiber, and specific history of DF definition or quantification methodology exists. Research in dogs and cats could affect DF's definition, and strategies for determining if dogs and cats have DF requirements are discussed. Research related to the effects of DF on digestibility, fecal parameters, gastrointestinal motility, intake, metabolism, and the immune system of dogs and cats are reviewed. Finally, applicable to all species, future research strategies to clarify the effects of DF are proposed.