Making sense of the wide variety of commercially available phytase products can be a daunting prospect. This can often lead to a poultry producer feeling confused and frustrated. That is why we at Chemuniqué believe that the only way to separate the best from the pretenders is with scientifically supported evidence.
An example of such scientifically supported evidence is a paper that was published in the journal of Agricultural and Food Chemistry by Menezes-Blackburn et al. (2015), entitled: “Performance of Seven Commercial Phytases in an in Vitro Simulation of Poultry Digestive Tract.” The aim of the study was to cut through all the marketing claims and hype, and look at the science behind the various commercially available phytase products by comparing the biochemical properties of each of the different commercially available phytase products, as well as their efficacy under in vitro conditions that simulated the digestive tract of the bird.
The parameters used to measure the biochemical properties of the different enzymes included phytase activity at different pH points, which reflected those found in the forestomach (crop), proventriculus, and gizzard where it is believed the majority of phytate degradation occurs. Lastly, the paper examined the effect the different phytase products had on the amount of phytate (IP-6) and IPtotal degraded as well as the amount of inorganic phosphate (Pi) released at various dose levels.
The results are in
What the researchers found was that no two commercially available phytase products are created equal, but that significant benefits associated with supplementing a Buttiauxella spp. phytase (BSP) included the following (Figure 1):
- The highest phytate-degrading capability vs all other phytase enzymes of 235% at pH 3.0 ;
- high activity in the presence of enzyme-degrading pepsin; and
- the best reduction in IP6 and increased Pi liberation at a lower dose.
The phytase activity at a low pH in the gastric stomach or gizzard/proventriculus is probably the most valuable attribute of a phytase, since it allows the rapid and more complete degradation of phytate before it can bind calcium. By degrading all of the phytate in the stomach, one prevents negative effects of phytate on phosphorus and amino acid digestion in the intestine and improves live performance.