Phytase

[SourRoses]

I noticed this item on a feed label that I hadn't heard of before.
My question is if this is something we should be thinking about when feed shopping?
Do all feeds have Phytase and just don't list it? Is this meant to be a selling point/gimmick?

From the label:

Phytase (A. Oryzae) (Min)....... 227 FYT/LB
One phytase unit (FYT) liberates one micromole of inorganic phosphorus per minute from sodium phytate at PH 5.5 and 98.6 F.
Contains a source of phytase, Ronozyme HiPhos GT, which can hydrolyze phytate increasing the digestibility of phosphorus in diets containing phytin-bound phosphorus.

 

[U_Stormcrow]

I got this.

Its an addative, and often found among the laundry list of pre and probiotics.

Plants store the majority of their phosphate as phytate, which chickens can't actally digest/absorb. Which is why the phoshorus in the vegetable components of their feed is basically ignored. Most feeds end up containing some non-plant sourced, non-phytate phosphorus to meet the chicken's nutritional needs. Adding phytase is essentially an enzyme which helps them to digest and absorb some of the phytate-bound phosphorus in the diet, making it more bioavailable to them.

So, **IF** there's plenty of phosphorus bound as phytate in the plant ingredients of the feed and **IF** the chicken's gutt is the right temp, **AND** the right pH, **AND** the feed spends enough time there, some portion of the bound phosphorus will be released. Hopefully turning a deficient feed into a better feed. How successful it might be is a matter of guesswork.

Why do I call it deficient??? Because most biological processes (apart from shell formation) use calcium and phosphorus in a 2:1 ratio. Since baseline calcium for all birds is 1% +/-, baseline phosphorus should be at least 0.5% (more rescent studies suggest chickens aren't as efficient at absorbing phosphorus as calcium and 0.6-0.7% is a better target. This feed has 0.45%....

 

[U_Stormcrow]

To be clear, I am NOT against the addition of phytase - it can't hurt and may be quite helpful - there's just no way to know how helpful it is. Id rather start with a decent amount of non-phytate phosphorus and have phytase in addition, rather than start with a deficiency and hope.

 

[Lazy J Farms Feed & Hay]

Phytase is one of the most impactful discoveries in monogastric feeds in the past 30 years. The use of phytase to release Phytin-Bound phosphorus in grains has allowed the feed industry to use dramatically less phosphorus in poultry and pig feeds. I would actually prefer to have rations WITH phytase since the ancillary benefits are slight improvements in amino acid and energy digestibility because of the way the phytase enzyme attacks the phytin ring structure.

 

[U_Stormcrow]

Phytase is one of the most impactful discoveries in monogastric feeds in the past 30 years. The use of phytase to release Phytin-Bound phosphorus in grains has allowed the feed industry to use dramatically less phosphorus in poultry and pig feeds. I would actually prefer to have rations WITH phytase since the ancillary benefits are slight improvements in amino acid and energy digestibility because of the way the phytase enzyme attacks the phytin ring structure.

Thanks! I don't suppose you are hearing anything about changing feed labels to give some suggestion as to how much phoshporus is expected to be released from its phytic acid binding under "normal" conditions?

I could do some back of napkin math and make some huge assumptions, but... that really doesn't comfort me much

 

[Lazy J Farms Feed & Hay]

Thanks! I don't suppose you are hearing anything about changing feed labels to give some suggestion as to how much phoshporus is expected to be released from its phytic acid binding under "normal" conditions?

I could do some back of napkin math and make some huge assumptions, but... that really doesn't comfort me much

Do you want the Available Phosphorus or STTD Phosphorus release values? The release is partially dependent on the source.

 

[U_Stormcrow]

Do you want the Available Phosphorus or STTD Phosphorus release values? The release is partially dependent on the source.

and that's why I was thinking I'd have to make some huge assumptions. Is there a "thumb rule" you are using in the industry to ballpark things for the typical soy/corn/wheat feed mix?

 

[U_Stormcrow]

Cause I know phytic acid has a molecular weight around 600g/mol, and that each molecule of phytic acid contains 6 P atoms (weight 30g/mol ea), so if 100% liberation could be achieved, the available P would be about 1/3 of the total phytic acid content as a theoretical max. I need to check sources for typical contents in various feed stuffs though...

 

[Lazy J Farms Feed & Hay]

1,000 units of a "typical" phytase releases between 0.10 and 0.15 percentage units of Available phosphorus