EN
The studies have been carried out on 49 lambs of Polish Longwooled breed, aged from 1 to 20 days. The purpose of the work was to determine insulin secretive reactions and the changes in the glucose level following glucose and fructose administration intravenously and orally, and lactose and saccharose per os. Glucose and fructose were given intravenously as a 40°/o solutions, saccharose orally also as a 40%> solution while lactose as a 20% solution. All the sugars were administered at a dose of 1 g/kg body weight. The examinations in lambs were performed after 4 hour starvation diet. The highest secretive reactions appeared following intravenous infusion of glucose resulting in its increased level from 11.9 uU per 1 ml at 10 min after glucose application. Glucose given orally caused an increase of insulin level from 24.4 uU/ml to the highest mean value of 58.7 uU/ml at min 30 after the termination of sucking. Intravenous influsions of fructose brought about an increase of plasma insulin from 11.0 uU/ml to 33.4 uU/ /ml at min 20 from the termination of infusion while oral intake did not evoke any change in the plasma insulin concentration. Oral intake of lactose caused an increase in plasma insulin concentration from 23.4 uU/ml to the highest mean value of 53.6 uU/ml, while saccharose did not influence the plasma insulin concentration.