Adding functional fibers in pig and poultry diets has already become mainstream in the design of antibiotic-free nutrition programs. The concept behind functional fibers is that of feeding beneficial gut bacteria to outmatch potential pathogens. Given that good bacterial are naturally dominant inhabitants of the animal gut, it is quite easy for them to exclude the opportunistic pathogenic ones. But, this involves the selection of a functional fiber source that helps them the most during stress periods. The question thus becomes one of sourcing and perhaps mixing of several fibers.
Early in my career as a consulting nutritionist, I started using functional fibers in the form of specific ingredients, such as wheat bran or sugar beet pulp, among several others. My rationale was that by selecting a wholesome ingredient I had the benefit of using more than one type of functional fibers. A decade ago, fibers in purified form were still newcomers and suffered from the general over-marketing exhaustion common to all additives. As such, I was bypassing purified sources of functional fibers. For example, instead of purified inulin, I have often used chicory pulp (a primary source for the purified inulin).
But, science and technology advances and new forms of fibers have emerged, and these merit a fresh look. Let’s take, for example, wood lignocellulose, which is not a purified fiber source, but it contains such a high level of lignocellulose (above 50 percent) that becomes virtually an additive. Another is that of extruded bran, specifically that from soya. It is not a purified source, but with the extrusion we have a different profile of fibers and perhaps other components that can have a similar function. Is extruded soy bran an ingredient like wheat bran, or does it now become a new additive?