Keynote on Phytase use in Poultry

December 3, 2020

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Phytase was developed to reduce the diffuse phosphorus pollution from intensive agriculture.
First commercialised in 1991, phytase is now present in over 60% of monogastric feed, and possibly even in a higher percentage of poultry diets,
Since first commercial utilisation, phytase has mainly been considered to be a tool to increase phosphourus (P) availability/digestibility from vegetable sources and so reduce the inclusion of higher cost P sources.
Here, phytase releases the P bound in the phytate molecule, increasing the availability/digestibility of this mineral to the animal.
Thus, increasing the inclusion rate of phytase would be expected to release additional P from the indigestible feed phytate and consequently allow an even greater substitution of higher cost P sources.
Several trials with higher doses of phytase using diets with normal levels of P have already shown better poultry performance, but this increase of performance was always correlated to an increase in P digestibility even if the diet did not have lower levels of P.
Phytases are digestive enzymes which release plant phosphorus from phytic acid.
Monogastric animals lack sufficient phytases to release the phosphorus.
Adding extra phytases to the diet increases phytate breakdown and consequent utilization of plant phosphorus.
If more phosphorus is available naturally, then less of this substance has to be added to the diet. This greatly reduces feed costs.
Correct enzyme:

a) The concept of using phytase at high doses to reduce the anti-nutritional effect of phytate means that there is an opportunity to redefine nutritional knowledge.

b) When using a high dose of phytase to reduce or eliminate the anti-nutritional effects of phytate, special attention needs to be paid to the choice of the correct enzyme.