Absorption of glucose and galactose and digestion and absorption of lactose by the preruminant calf

摘要: 1. Uptakes of glucose, galactose, glucose+galactose and lactose from the intestine were studied in preruminant calves fitted with cannulas proximal small intestine, slaughtered calves. Responses concentration blood sugar to presence also investigated.2. Glucose galactose absorbed at about same rate when present separately. The for each approached a maximum increasing lumen.3. When glucose together, absorption was greatly depressed; that virtually unaffected. Consequently, fed mixtures where relative high, depressed. In more distal had fallen, rapid. Both sugars efficiently during their passage through whole but different sites.4. Galactose appeared after alone given conversion some into always occurred. Results experiments which [14C]galactose, together infused duodenum calf suggested under these conditions depressed such an extent nearly all entering converted glucose.5. Lactose hydrolysis occurred much rapidly than its constituent monosaccharides. Thus, calves, accumulated lumen intestine. A similar accumulation loops rate-limiting step total young not, therefore, stage, as reported other mammals. released manner described above galactose.