Currently, gastroscopy is the gold-standard tool for diagnosing equine gastric ulcer syndrome (EGUS). Recently, a team led by Michael Hewetson of the University of Helsinki, sought to determine the accuracy of using a blood sucrose permeability test instead, which is less invasive and not as expensive.
Due to the large molecular size of sucrose, it can’t permeate the gastrointestinal lining unless the mucosa is diseased. As such, if testing reveals high levels of blood sucrose after oral sucrose administration, it is a good indicator that the animal is suffering from EGUS.
It was noted, however, that while this type of testing has been useful in adult horses, the same can’t be assumed for foals because there are changes in the gastrointestinal lining of the stomach which occur in the first six months of life that may alter permeability of sucrose.