title: Effect of soy protein on intestinal absorptive ability of calves by the xylose absorption test.
abstract: Five calves per group were fed whole milk (control) or one of three milk replacers with one-thrid of the total protein provided by a soy product. Soy products were Promocaf (a commercial soy protein concentrate), an experimental soy flour. After a 24-h fast, calves were fed xylose solution. Urine was collected for 5 h. Jugular blood was sampled at 0, .5, 1, 1.5, 2, 2.5, 3, 4, and 5 h after xylose administration. Xylose tests were weekly on each calf through 5 wk of age. Urinary xylose excretion, as a percentage of xylose fed, was higher in the control group during the last 4 wk than in groups fed milk replacers. Mean urinary xylose excretions during 5 wk from calves sampled 5 h after xylose administration were 12.4, 4.2, 4.2, and 4.3% of xylose administered for calves fed milk, soy flour, soy protein concentrate, and Promocaf, respectively. Mean increases in peak of xylose concentration in plasma were 55.7, 44.4, 42.8, and 45.3 mg/100 ml. Peak values for control calves were higher than those for calves fed soy products at wk 4 and 5. Times required to reach peak value did not differ significantly. Neither xylose concentration of plasma nor urinary xylose excretion differed among the groups fed soy products.
mesh_terms: D000818:Animals; D002417:Cattle / Q000378:metabolism*; D007408:Intestinal Absorption; D008297:Male; D008894:Milk Proteins / Q000378:metabolism; D014674:Plant Proteins, Dietary / Q000378:metabolism*; D013025:Glycine max; D014994:Xylose / Q000097:blood / Q000652:urine
chemical_list: D008894:Milk Proteins; D014674:Plant Proteins, Dietary; D014994:Xylose