Small intestine digestible

The bolus passes from the stomach directly into the small intestine, where enzymatic digestion mainly takes place. This means that enzymes break down proteins into their amino acids, starch into individual sugar molecules and fats into glycerol and fatty acids. Anything that was not digested in the small intestine passes into the large intestine for further digestion by microorganisms.

In horses, it is important that as little undigested starch as possible reaches the large intestine, as this can cause an imbalance in the colon flora (dysbiosis) and lead to diseases such as laminitis. Therefore, hard-to-digest cereal starch from, for example, maize or barley should be hydrothermally treated.

Small intestine digestibility is also important for protein, as only amino acids that are digested and absorbed before the large intestine (appendix = first section of the large intestine) can be utilised by the horse. The abbreviation for this type of protein or these amino acids is pcv (precaecal, i.e. digestible before the large intestine). pcvXP is small intestine digestible protein, pcvAS is small intestine digestible amino acids.