The importance of glycogen at the termination of the embryonic existence of Gallus domesticus

The Gaseous Environment of the Chick Embryo in Relation to Its Development and Hatchability

“…Effects of these imbalances may be delayed beyond hatching; however, the period of hatching is most important in this study for it is the measure of tolerance and any event which would upset the normal preparation for this critical period could determine the ability to hatch. Glycogen accumulation in the various organs of the embryo and its importance in hatching (Beattie, 1964;Freeman, 1965) testifies to the need for this preparation.…”

Expression of the Genes for the Mitochondrial and Cytosolic Forms of Phosphoenolpyruvate Carboxykinase in Avian Liver during Development

“…In addition, the fully developed avian embryo contains a large amount of glycogen [18], Thus gluconeogenesis occurs principally from amino acids and glycerol during development in the chicken. The presence of hepatic PEPCK-C during avian development is nec essary for maximal glucose production from amino acids [5], It is interesting to note that chicks, which contain only PEPCK-M in the liver, grow on a 'carbohydrate-free' diet in which soybean oil is supplied and become stunted in growth and hypoglycemic when fatty acids are substituted [19].…”

Carbohydrate metabolism in the domestic fowl

“…At the end of the incubation period, hepatic glycogen is rapidly metabolized (Muglia & Massuelli, 1934;Gill, 1938) and falls from 19.0 mg/g liver in the 18.5-d-old embryo to 1.6 mg/g liver I d after hatching with a concomitant increase in blood sugar (Freeman, 1965). Glycogen probably serves as an energy source for hatching.…”