Effect of egg turning and fertility upon the sodium concentration of albumen of the Japanese quail

Abstract

1. The effects of egg turning and fertility upon sodium concentration of albumen of the Japanese quail is described for up to 72 h incubation. 2. For incubated eggs the sodium concentration of albumen adjacent to the yolk sac was lower than that from albumen next to the shell. Static incubation increased the magnitude of this difference, such that albumen adjacent to the yolk sac was substantially depleted of sodium. This was found at the yolk equator and the yolk vegetal pole of both fertilised and unfertilised eggs. 3. Unincubated eggs also had a lower sodium concentration of albumen adjacent to the yolk sac compared with albumen next to the shell. 4. After 48 h of incubation yolk sodium concentration was substantially lower than albumen sodium concentration in both fertilised and unfertilised eggs, whether eggs were turned or not. 5. It is concluded than in unturned eggs the depletion of sodium from albumen adjacent to the vitelline membrane is not produced by ion transport processes but results from a passive movement of sodium into the yolk. Egg turning reduces the magnitude of the depletion of sodium from the albumen adjacent to the yolk sac by stirring the albumen, so permitting the full expression of ion and water transport across the blastoderm into the yolk sac.

Physiological determinants of the internesting interval in sea turtles: a novel ‘water-limitation’ hypothesis

“…This value could reasonably be deemed representative for all sea turtles, as it is not very different from that reported for a freshwater turtle (92.5 mmol kg -1 ) [62], for avian albumen (approx. 82 mmol kg 21 ) [63], or for another report from loggerheads if we assume the total 'salts' reported were entirely sodium chloride (102 mmol kg 21 ) (calculated from [48]). Therefore, we will adopt 95.7 mmol kg 21 as the albumen sodium concentration for later calculations.…”

Electrolyte and Water Balance of the Early Avian Embryo: Effects of Egg Turning

“…Hence, in unturned eggs, they suggested, a depletion of sodium from the layer of albumen adjacent to the blastoderm, due to a lack of`stirring', would result in insuf®cient sodium for this process. Latter and Baggott (1996) investigated this proposal directly using eggs of the Japanese quail incubated from 24 to 72 hours. They tested the speci®c predictions that sodium would be depleted from the albumen adjacent to the yolk sac and that this would occur in eggs only where active sodium transport occurred, i.e.…”

Effect of egg turning and incubation time on carbonic anhydrase gene expression in the blastoderm of the Japanese quail (Coturnix c. japonica)

“…Latter and Baggott (1996) found that unincubated eggs had a low sodium concentration in the albumen adjacent to the vitelline membranes. Egg turning increased the sodium concentration at this location by the same magnitude throughout the period of SEF production, whereas unturned eggs retained this 'depleted layer'.…”