Knowing how much phosphorus your phytase can release is vital in understanding how much of a cost saving it could deliver.
Evaluating phosphorus equivalency of phytases, features EMEA Technical Director Dr Rob ten Doeschate, who explains that phosphorus release still remains at the core of phytase selection criteria for customers:
“In recent years, the functionality of phytases has evolved – and there is greater awareness of their ability to release additional minerals and protein beyond phosphorus. However, it is almost inevitable that feed producers’ first question when evaluating a phytase is: ‘How much phosphorus can this product release?’ And the answer is not as straightforward as it may seem.”
Dr ten Doeschate explains that the best way to determine P-equivalency of a phytase is to compare the response achieved whilst using the phytase with a P-dose response curve established under controlled conditions.
Outlining the process used to set matrices, Dr ten Doeschate explains that a product’s confidence limits also have a key role in offering assurances on efficacy.
“If a supplier has a sufficiently large database of trials, they can use holo-analysis to set a matrix for their product. This process of gathering all the data for analysis also allows for the implementation of a confidence limit. It is important to note that not all phytases have the same confidence limits, so won’t necessarily always deliver the phosphorus required.
“If you wish to truly compare like for like, you can examine what the nutrient release would look like without a confidence limit in place. If we take Quantum Blue as an example, we set a 90% confidence limit, meaning that the expected phosphorus release is expected to be achieved 90% of the time. The average response is substantially higher and this should be considered when comparing products.”
Dr ten Doeschate explains that it is important to consider not just the amount of phosphorus a phytase can release – but whether sufficient phytate phosphorus exists in order to justify the use of a high dose of phytase with a phosphorus matrix:
“Variation will inevitably come into play, in terms of the phosphorus available from phytate – so it is important to check the ingredients of a diet regularly. This is where Near Infrared Spectroscopy delivers benefits: it can be used to check the phytate level in raw materials and the finished feed, so you can be sure there is enough phytate for the matrix that you are using.”
June 5, 2017 - AB Vista