Basically the results of a forage analysis can be divided into four different portions. These are protein, fiber, minerals and Relative Feed Value. The protein portion is based on the nitrogen content of the sample and considers both true protein and non-protein nitrogen. Animals can utilize both these to some degree. Crude protein analysis gives no indication whether any heat damage has occurred to the forage sample.
Ruminant animals are able to utilize a portion of both types of protein.
Crude protein analysis gives no indication that heat may have reduced the availability of the protein. If excessive heating of forages has occurred an analysis indicating bound protein, insoluble protein or unavailable protein needs to be requested. Knowing the crude protein value of your feeds frequently reduces the cost of rations. This means that as the NDF increases the animals are able to consume less. This is one reason why it is important to harvest the forage at the desirable stage of plant maturity.