Nutritional Value of Glycerin for Pigs Fed a Mixture or on Top Diet

The objective of this study was to determine the digestibility of glycerin through a mixture (MIX) or inserted on top of feed (ONTOP) using chromium indicator (Cr) and total collection (TC) methods. A total of 12 barrows 42.63±4.23 kg in a 2x2 + 1 factorial scheme, with two forms of inclusion of the test ingredient (MIX or ONTOP), two digestibility methods (Cr or TC) and a basal diet (BD). The digestibility coefficients (DC) of dry matter (DM), ash, organic matter (OM), ethereal extract (EE), and digestible (DE) and metabolizable energy (ME) values of glycerin were determined. The DE and ME values of glycerol were 3443 and 3411 kcal/kg and 3356 and 3293 kcal/kg for Cr and TC, respectively. There was no difference in MIX or ONTOP, except for DC EE. The DC and energy values obtained by Cr were lower than those obtained by CT. The inclusion of the test ingredients in the MIX and ONTOP forms did not present any difference, whereas Cr underestimated the nutritional value of glycerin for pigs.