title: Influence of an indigestible material on energy excretion by roosters and on true metabolizable energy of corn.
abstract: The influence of an indigestible and noncombustible material, silica gel (SG) on the excretion of energy by roosters and on the true metabolizable energy (TME) of corn was determined. Energy excretion by fasted roosters increased linearly with each increment of SG force-fed. The equation, energy excreted (kcal/24 hr) = 9.87 + (.47 x g SG) described this effect of SG. The data also showed that 24 hr was insufficient time for SG to completely clear the digestive tract, irrespective of amount force-fed. The TME of corn was 4.05 kcal/g dry matter when the grain was force-fed alone to roosters, when corn was force-fed in mixtures containing increasing proportions of SG, the TME of corn decreased with each increment of SG in the mixture. It was concluded that the extra energy excreted as a consequence of the presence of SG in mixtures with corn caused an underestimation of corn's TME. The regression coefficient relating energy excretion to amount of SG forced-fed in the previous trial was used to correct energy excretion by roosters fed corn-SG mixtures, and corrected TME's for corn were calculated. The average corrected TME of corn was 3.97 kcal/g dry matter. These data illustrated that an indigestible material passing through the gastrointestinal tract of the chicken changed the amount of fecal metabolic energy excreted and, consequently, influenced the TME value of companion feedstuffs when the conventional TME assay procedure was used.
mesh_terms: D000821:Animal Feed; D000818:Animals; D002645:Chickens / Q000378:metabolism*; D004063:Digestion; D004734:Energy Metabolism; D008297:Male; D012822:Silicon Dioxide / Q000378:metabolism; D003313:Zea mays
chemical_list: D012822:Silicon Dioxide