Protein degradation with various degrees of severity takes place during silaging. This has consequences for the nutritional value. The amount of bypass protein (UDP) and usable protein (nXP) declines while the amount of NPN compounds rises. There are also conversion and degradation processes within fraction A, the NPN compounds. If the fraction still consists mostly of free amino acids, there may be a more or less severe breakdown into ammonia and biogenic amines, depending on the process.
Please note our documents on the protein requirements of cows, which are available for download: