Effects of Phlorizin on Glucose Kinetics in the Bovine

Abstract

Glucose excretion from phlorizin was established in calves given different diets and/or different phlorizin doses; the ability of phlorizin to alter gluconeogenesis then was investigated. In calves fed hay, maximum glucose excretion of up to 313 g/day was caused by about 2g of phlorizin per day. When calves were given only single doses of phlorizin subcutaneously, there was an increased glucose excretion with each increase in phlorizin up to 2g with either a hay or a grain diet. At all phlorizin dosages, calves fed a high-grain diet had over two times greater glucose excretion than those fed hay. In three grain-fed calves where phlorizin caused an average glucose excretion of 360 g/day, the only parameter of glucose kinetics that changed from control calves not given phlorizin was irreversible loss, which increased 8.2 g/h. Neither pool size nor total entry rate was affected. Phlorizin did not increase gluconeogenesis in fed ruminants.