title: Effect of food deprivation on D-xylose absorption test results in mares.
abstract: A D-xylose absorption test was conducted on 4 healthy mares deprived of food for 12, 36, 72, and 96 hours before the test, with a 13- to 15-day adjustment period between each test. Maximal plasma concentrations after 72 and 96 hours of food deprivation were approximately 36% lower than those obtained after the 12- and 36-hour periods (P = 0.0001). Absorption curves were flatter and the decrease in plasma concentration was slower after the 72- and 96-hour periods of food deprivation. The rate of D-xylose absorption (P = 0.0108) and the initial rate of urinary excretion (P = 0.0117) were slower at 72 and 96 hours. Gastric emptying appeared to be progressively delayed with food deprivation, as evident by the delay in peak D-xylose excretion in urine (P = 0.0268). Areas under the plasma concentration-time curves and quantitites of D-xylose excreted in urine were similar for all periods of food deprivation, evidence that the same amounts of D-xylose were absorbed, despite changes in the plasma curve. A 15-hour collection period was sufficient to recover all D-xylose excreted in the urine, and during all periods 9.8 +/- 0.6% (mean +/- SEM) of the oral dose was eliminated in the urine.
authors: Department of Clinical Studies, University of Pennsylvania, Kennett Square 19348.
authors: D E
authors: DE
authors: Freeman
authors: P L
authors: PL
authors: Ferrante
authors: D S
authors: DS
authors: Kronfeld
authors: W
authors: W
authors: Chalupa
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000818:Animals; D005260:Female; D005508:Food Deprivation; D006736:Horses / Q000378:metabolism*; D007408:Intestinal Absorption; D013997:Time Factors; D014994:Xylose / Q000097:blood / Q000378:metabolism* / Q000652:urine
chemical_list: D014994:Xylose