Metabolism of naturally occurring [13C]glucose given orally to horses.

This research study investigates the metabolism of naturally occurring [13C]glucose in horses through the use of oral glucose tolerance tests (OGTT) with both maize and beet glucose.

Objective of the Research

• The goal of this study was to assess how horses metabolize naturally occurring [13C]glucose, a type of glucose that is comprised of the heavier carbon-13 isotope. The metabolism was measured by determining the 13CO2/12CO2 ratios in the air expired by horses after giving them a standardized dose of glucose orally (OGTT).

Methodology

• The research involved performing OGTT on five horses. Two sources of glucose were utilized for this purpose – maize and beet. Maize naturally has a higher 13C concentration than most plants.
• During the OGTT, researchers measured the 13CO2/12CO2 ratios in the expired air of horses. This was done using isotope mass spectroscopy, a commonly used method for determining the isotopic composition of elements.
• The 13CO2/12CO2 ratios after OGTT performed using maize glucose were compared with the ratios after OGTT performed using beet glucose. The ratios were also measured during periods when the horses were not fed.

Findings

• The study revealed that all the horses were glucose tolerant as indicated by the outcome of the OGTT.
• There were minimal changes in the 13CO2/12CO2 ratios after the OGTT was performed using beet glucose.
• When the horses were not fed, the 13CO2/12CO2 ratios significantly decreased (with a P value less than 0.01).
• After administering maize glucose orally, the 13CO2/12CO2 ratios reached maximum increases 5 hours after dosing, and returned to baseline values 15 hours after dosing.

Significance

• The results of the study provide insights into how horses metabolize naturally occurring [13C]glucose. These findings could potentially be used to further understand glucose metabolism in horses, guiding the development of dietary plans for horses, early detection of metabolic disorders, and effective treatments.