Analysis of liver glycogen in chicks.

The glycogen levels in homogenates from livers from 3- to 4-week-old broilers were measured using alkaline digestion and ethanol precipitation followed by direct hydrolysis with amyloglucosidase. Glycogen was determined with glucose oxidase. Glycogen levels were not affected by rapid freezing in liquid nitrogen and storage at -10 C. Glycogen was stabile at 4 C for at least 1 hr; however, at room temperature, over 50% of the glycogen was lost within 1 hr. Homogenization with .05 M ethylenediaminetetraacetate (EDTA) prevented this loss. Liver glycogen decreased rapidly (within 1 hr) after feed withdrawal and was sometimes undetectable within 2 hr. There was considerable variation in glycogen levels among individual birds. Liver glycogen levels were up to 50% higher at 1100 than at 0800 hr.