Poultry Enzymes

Many feed ingredients are not fully digested by livestock. However, by adding enzymes to feed, the digestibility of the components can be enhanced. Enzymes are now a well-proven and successful tool that allows feed producers to extend the range of raw materials used in feed, and also to improve the efficiency of existing formulations. Enzymes are added to the feed either directly or as a premix together with vitamins, minerals and other feed additives. In premixes, the coating of the enzyme granulate protects the enzyme from deactivation by other feed additives such as choline chloride. The coating has another function in the feed mill - to protect the enzyme from the heat treatments sometimes used to destroy Salmonella and other unwanted microorganisms in feed. Coating of enzymes can be replaced by thermostable enzymes can be derived from thermophobic micro -organisms. Liquid enzymes are used in those cases where the degree of heat treatment (conditioning) for feed is high enough to cause an unacceptable loss of activity in the enzyme. Liquid enzymes are added after conditioning and liquid dosing systems have been developed for accurate addition of these enzymes. Addition of enzymes can be done during the palletisation of feed or liquid enzymes can be fed directly to the animals through water line, specially in poultry cases. A wide range of enzyme products for animal feed are now available to degrade substances such as phytate can be degraded by phytase, glucan can be degraded by beta glucanase, starch can be hydrolysed by amylase, protein can be degraded by proteinases, pectin-like polysaccharides by pectin methyl esterases, xylan by xylanases, raffinose and stachyose by blends of mannanase and pullulanase. Hemicellulose and cellulose can also be degraded by blends / like of whole cellulases. As revealed by the many feed trials carried out to date, the main benefits of supplementing feed with enzymes are faster growth of the animal, better feed utilisation (feed conversion ratio), more uniform production, better health status, and an improved environment for birds due to reductions in 'sticky droppings' from chickens.

Cereals such as wheat, barley and rye are incorporated into animal feeds to provide a major source of energy. However, much of the energy remains unavailable to monogastrics due to the presence of non-starch polysaccharides (NSP) which interfere with digestion. As well as preventing access of the animal's own digestive enzymes to the nutrients contained in the cereals, NSP can become solubilised in the gut and cause problems of high gut viscosity, which further interferes with digestion. The addition of selected carbohydrases will break down NSP, releasing nutrients (energy and protein) as well as reducing the viscosity of the gut contents. The overall effect is improved feed utilisation and a more 'healthy' digestive system for monogastric animals. AETL has launched its universal blend of enzymes - MAXIGEST way back in 1994 which is working effectively on all diet combinations for poultry.

Around 50-80% of the total phosphorus in pig and poultry diets is present in the form of phytate (also known as phytic acid). The phytate-bound phosphorus is largely unavailable to monogastric animals as they do not naturally have the enzyme needed to break it down - phytase. There are two good reasons for supplementing feeds with phytase. One is to reduce the harmful environmental impact of phosphorus from animal manure in areas with intensive livestock production. Phytate in manure is degraded by soil microorganisms, leading to high levels of free phosphate in the soil and, eventually, in surface water too. Several studies have found that optimising phosphorus intake and digestion with phytase reduces the release of phosphorus by around 30%. Estimates says that the amount of phosphorus released into the environment would be reduced by 2.5 million tonnes a year worldwide if phytases were used in all feed for monogastric animals.

The second reason is based on the fact that phytate is capable of forming complexes with proteins and inorganic cations such as calcium, magnesium, iron and zinc. The use of phytase not only releases the bound phosphorus but also these other essential nutrients to give the feed a higher nutritional value.