Most feed ingredients contain moisture. Nutritionists describe feed weight on a dry weight basis, called "dry matter basis," which is the weight if all moisture is removed, or an "as fed basis," which is the weight with moisture included. Farmers make many calculations of dry matter weight of feeds in preparing and comparing feeds and monitoring feed intake. Use weight of a feed and percent dry matter in a simple calculation to determine dry matter weight.
Things You'll Need
 Feed dry matter chart
 Calculator
 Oven
 Scale

Determine the feed ingredient weight.

Determine the feed ingredient percentage dry matter. Consult charts for ingredients with stable dry matter percentage such as grains. For example, in the National Research Council's "Nutrient Requirements of Dairy Cattle." For ingredients with variable dry matter percentage, determine dry matter using conventional or microwave oven procedures or near infrared reflectance spectroscopy as described by the National Forage Testing Association.

Divide the dry matter percentage by 100. For example, if the dry matter percentage is 40 percent, divide 40 by 100 to get 0.4.

Multiply the number calculated in step 3 by the weight of the feed ingredient. In the example, if the weight of the ingredient is 10 pounds, the dry matter weight is 10 pounds times 0.4, or four pounds.
References
 National Forage Testing Association
 "Nutrient Requirements of Dairy Cattle", National Reseach Council; 2001
 Utah State University Cooperative Extension
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