This table lists the bio-availability of the various feeds used for additional protein in horses but they are based on human studies. Values that have a range is because of different information available.
The bio-availability of proteins can vary between different horses and can even differ in one horse depending on factors such as gut inflammation and fasting. I think it safe to assume that horses with gut inflammation or who are on medications (especially proton pump inhibitors – ulcer medication) will definitely have a reduced absorption and bio-availability of proteins. In addition, horses in carbohydrate dependency (fed sugar every day of the year) will also be self consuming their own proteins (top line loss). Feeding excessive amounts of proteins may also cause the horse to convert the fed proteins into sugar in the gut when the amount of daily carbohydrates in excess of needs are not reduced..
Basically, this list is to show you that in testing conditions, not all proteins are absorbed equally. Feeding the best quality protein (no hulls, no fiber, no sugar, no oils) with the best bio-availability AND offering several protein sources will give your horses the best chance of absorbing all the amino acids to produce a great top line, a robust immune system, and a strong connective tissue system.
|Dried Split Peas||65%|
|Grass and Legume Hay||50 – 56%|
|Hemp Seeds||33 – 87%|