I don't know which specific bag you are looking at, but there should be a label that gives the analysis of the stuff in the feed. This normally gives percentage protein, salt, calcium, and several other things. That is not percent of daily requirements or anything like that. If it gives 16% protein, for example, it means that the bag of feed contains 16% protein.
You might look on the label to see if anything on the label corresponds to the percent you are seeing on the bag. It's likely percent protein, but I don't know that for sure. The feed I buy does not have a number like that, just the percents on the label.