Digestive load factor
See also: CUD
The digestive Load factor (CUD) is the introduced quantity of nutrient is different from that which, once digested, will be absorbed on the level of the intestine. The CUD is the percentage corresponding to the share of a nutrient which will not finish in the excrements. The CUD of the same nutrient can vary according to the nature of the other nutrients which accompany it.
example: the osseous fish have proteins of CUD higher than 95%
C'est-à-dire: 95% of proteins of this fish will cross the intestinal barrier to be metabolized by the organization.