Utilization of Carbohydrates Introduced Directly into the Omaso-Abomasal Area of the Stomach of Cattle of Various Ages,

Abstract

Blood reducing sugar responses were measured in 5 groups of dairy animals (mean ages: 22, 50, 136, 227, and 600 days) following ingestion of single test meals of each of the following in water: glucose, maltose, lactose, sucrose, amylose, amylopectin, acid-treated starch, and tapioca starch. Rate of administration was in proportion to body weight. Maximum increases in blood sugar (in mg/100 ml) after carbohydrate ingestion at the 5 ages, from youngest to oldest, were glucose: 134, 130, 76, 82, 50; lactose: 147, 117, 36, 37, 14; maltose: 31, 72, 30, 34, 17. Sucrose and starch did not cause appreciable changes in blood sugar at any age. Ingestion of sucrose and maltose caused diarrhea at all ages; diarrhea due to glucose and lactose was more frequent in the oider animals. No diarrhea resulted from ingestion of starch. Intravenous injection of glucose prior to ingestion of carbohydrate increased the sensitivity of blood reducing sugar as an estimator of absorption. Onset of absorption of hydrolytic products of starch was too late for the single glucose injection, at feeding time, to be of maximum value. Absorption of carbohydrates appeared to begin at about the following times (in minutes) after ingestion: glucose 15; maltose and lactose, 30 starches 30-60. Responses to starch administration were moderately increased when starch were autoclaved or heated in water suspension.