With so many products to choose from, it has become nearly impossible to discern which one does what and how to find the one to use.
A quick review of the most recent book of the European Symposium on Poultry Nutrition (ESPN) abstracts reveals a continuing focus on the enzyme phytase.
One can only wonder if there is need for so many different and diverse products, but that is a matter of a business-oriented discussion. What is of interest in the scope of this technical discussion is a very legitimate question that I have encountered, and answered, many times over: Are there real differences between the many commercial phytase products?
The correct answer is that, yes, there are substantial differences among phytases, not only in the way they go about attacking the phytate entity, releasing phosphorus, but also in the amount of phosphorus they release and, of course, the origin of the enzyme that may affect not only its efficiency but also its technical quality aspects. So, not all phytase enzymes are created equal and not all of them work the same way or have the same efficiency.
First, let us distinguish between quality products and those that imitate them. We shall ignore the latter because there is no way in telling what was done to produce a lower-cost product and whether such interventions affect the result. We shall focus, instead, on quality products: those that deliver what they claim on the label.
So, in choosing between phytase A versus phytase B, one has to answer two very basic questions. First, what is the amount of phosphorus each product releases per unit of phytase included in the final feed? Say, if you add 1 kilogram of phytase A product as recommended by the manufacturer (note, here I am not referring to active compound inclusion, but rather on final product inclusion), do you receive back the 0.1% available or digestible phosphorus, as claimed by the manufacturer? If yes, then you should be able to review available research conducted appropriately. Second, what is the cost of inclusion to receive this benefit? Only then you can compare the two products on a benefit-per-cost ratio and select the most convenient. Comparing quality products otherwise means little under commercial conditions.
Note, however, that additional quality aspects or extra claims may or may not sway your decision toward a different direction. But, when it comes to the basic claim of phosphorus release, there is no other way. All quality phytases must deliver the phosphorus they promise regardless of their origin, name, mode of action or inclusion rate. At this level of discussion, it matters only which quality product does the job at the least possible cost.
