EQUATIONS FOR RECIPROCAL CONVERSIONS OF STARCH EQUIVALENT AND TOTAL DIGESTIBLE NUTRIENT VALUES
In order to facilitate reciprocal conversions of Starch Equivalents (SE) and Total Digestible Nutrients (TDN) values of feeds, multiple regression equations were computed for three different groups of feeds (concentrates, green roughages and silages, and dry roughages. These equations are: for concentrates, green roughages and silages, and dry roughages, respectively.[Formula: see text]Where Y = percentage TDN, X1 = percentage SE, and X2 = percentage crude fiber and[Formula: see text]Where Y = percentage SE; X1 = percentage TDN, and X2 = percentage crude fiber.The addition of the crude fiber content as the second independent variable in each equation resulted in a slight but marked gain in accuracy, especially for green and dry roughages, when compared with simple regressions of TDN on SE or vice versa.