Improved animal health and performance always has been the goal of people associated with livestock production. Consequently, any feedstuff, feed additive, drug or other compounds that are capable of enhancing animal health or performance will interest producers, veterinarians, and animal nutritionists. Several compounds have been used to improve animal performance either by manipulation of the rumen environment (e.g., sodium bicarbonate) or by directly altering the composition and metabolic activities of rumen microorganisms (e.g., ionophores).
Digestion is the process of breaking down large, complex molecules, as provided by the birds’ feed, into smaller components that can be absorbed into the portal blood system. The process involves changes in both physical and chemical structures of most dietary components. Poultry feeds consist of a complex array of particles differing not only in chemical composition but also in size, hardness, solubility, and ionic characteristics.
Under ideal conditions, this array of particles and chemicals with different characteristics degrade slowly in a step-wise manner as feed passes from the mouth to the large intestine. Particle breakdown is a constant process, although the gizzard provides the major site of this activity.
Enzymes are largely responsible for molecular degradation, although their pH greatly influences their efficacy. When digestion is reduced, there will be reduced bird growth and/or increased feed intake. Indigestion may also cause problems with manure/litter management because non-digested residues in the large intestine often adsorb more water or produce feces that are more viscous.
Animal feed contains Cereals and Cakes. Cell walls of cereals are primarily composed of carbohydrate complexes referred to as Non-Starch Polysaccharides (NSP). ANFs present in these NSP (like ß-glucans and arabinoxylans) are non-digestible and form high-molecular-weight viscous aggregates in the gastrointestinal tract. They
Affect the digestive enzymes.
Cause endogenous losses
Reduce the rate of passage.
Stimulates pathogenic microbial proliferation.
Enzymes such as xylanase or ß-glucanase into diets having ANF can effectively decrease viscosity and consequently reduce the anti-nutritional effect of NSP. Cellulase, ß-Glucanase, Xylanase, and Pectinase can degrade plant origin cell wall polymers.