When expressing the nutrient composition of feed on a dry matter basis, which component is excluded?

When nutrient composition of feed is expressed on a dry matter basis, water is the component that is excluded. The dry matter basis focuses on all solid components of the feed, which include nutrients such as proteins, fibers, fats, and vitamins, while water is eliminated from this calculation. This is important in animal nutrition because it allows for a more accurate comparison of nutrient content across different feeds, regardless of their moisture levels. By removing water from the equation, researchers and nutritionists can better assess the energy and nutrient density of feeds, ensuring that animals receive the proper nutrition regardless of the water content in the feed.