This is an archived Horseadvice.com Discussion. The parent article and menus are available on the navigation menu below:
HorseAdvice.com » Horse Care » Equine Nutrition, Horse Feeds, Feeding » Grains and Concentrates for Horses, an Overview »
  Discussion on Phytic acid in grains
Author Message
New Member:
lou71

Posted on Monday, Nov 12, 2012 - 1:43 pm:

Hi there,

I'm currently studying nutrition at school and yes, a little knowledge can be dangerous! I'm leaning about how phytic acid in grains prevents the digestive enzymes from breaking down the nutrients (in essence, so that the grain survives it's trip through the digestive system, gets pooped out the other end, and goes on to grow another life!). In addition, apparently "up to 80 percent of the phosphorus—a vital mineral for bones and health—present in grains is locked into an unusable form as phytate. When a diet including more than small amounts of phytate is consumed, the body will bind calcium to phytic acid and form insoluble phytate complexes. The net result is you lose calcium, and don’t absorb phosphorus. Further, research suggests that we will absorb approximately 20 percent more zinc and 60 percent magnesium from our food when phytate is absent." (Weston Price Foundation).

So, I thought, does this apply to horses? And, apparently, it does. In the human world, they recommend soaking the grains overnight which helps reduce the phytic acid...and some grains (but not oats, unfortunately) contain enough Phytase to counteract the problem of phytic acid.

This is also interesting, when thinking about processed horse food..."Phytase is destroyed by steam heat at about 176 degrees Fahrenheit in ten minutes or less. In a wet solution, phytase is destroyed at 131-149 degrees Fahrenheit.31 Thus heat processing, as in extrusion, will completely destroy phytase—think of extruded all-bran cereal, very high in phytic acid and all of its phytase destroyed by processing. Extruded cereals made of bran and whole grains are a recipe for digestive problems and mineral deficiencies!" (Weston Price Foundation).

While soaking some grains will help reduce phytic acid, it doesn't do much to oats.

FINALLY...my question: based on the above, how do horses properly digest and gain nutrients from whole oats? I'm not sure that chewing really well would do it, but perhaps I'm wrong? Or perhaps the phytic acid thing is not a problem in horses?

If phytic acid is a concern, is there something we can feed with the oats to counteract the concerns?

I found one study in the Journal of Animal Science that relates to all this but to be quite honest, it's well over my head. Here it is in case of interest: https://www.animal-science.org/content/82/6/1756.full.pdf

Thank you for any thoughts or facts on this.
Member:
frances

Posted on Monday, Nov 12, 2012 - 3:47 pm:

Very interesting, Sarah, and quite worrying. I hope DrO has some reassuring answers for us!
Moderator:
DrO

Posted on Tuesday, Nov 13, 2012 - 6:06 pm:

Welcome Sarah,
While it is true that phytates can do most of what you say above this is passively taken into account by the actual trials done with actual foodstuffs. While the phytates negatively impact nutrition the amount fed overcomes the negative impact. More simply, the problem here is one of comparing the scientific facts you read about with the truth you observe everyday: horses do well when fed grains to supplement energy requirements for horses. Which are you going to believe your lying eyes or those written scientific facts?

Adult horses have done well when fed grains, unprocessed corn or oats, to supplement energy shortages in medium to high quality forages for thousands of years. Modern feeding recommendations are made on the basis of feeding trials done with the actual feedstuffs.

There is one place where phytates may have actually negatively impact nutrition, specifically calcium and that is when large amounts of bran is fed particularly to growing horses. Bran is not only high in phytates but also low in calcium. When fed in excess it can further impair the use of other sources of calcium causing a Cal deficiency or Ca / phos imbalance. The result has been called Bran's disease or Bi Head. More appropriately is the name secondary nutritional parahyperthyroidism. It is one of the reasons for our recommendations on limiting the amount of bran in the diet.
DrO
Home Page | Top of Page | Join Us!
Horseadvice.com is a BBB Accredited Business. Click for the BBB Business Review of this Horse Training in Stokesdale NC