AJP - Regulatory, Integrative and Comparative Physiology, Vol 242, Issue 1 121-R128, Copyright © 1982 by American Physiological Society
Embryonic oxygen consumption and growth of Laysan and black-footed albatross
T. N. Pettit, G. S. Grant, G. C. Whittow, H. Rahn and C. V. Paganelli
The constraints placed on diffusive gas exchange by the eggshell and the
adaptive features of embryonic respiration and metabolism in large Laysan
and black-footed albatross eggs (300 g) during prolonged incubation (65
days) were examined in naturally incubated eggs on Sand Island, Midway, in
the Northwestern Hawaiian Islands. A low eggshell gas conductance and slow
growth rate were associated with a relatively low oxygen consumption (MO2)
throughout incubation. Just prior to internal pipping (IP) of the inner
shell membrane and penetration of the air space, the MO2 (pre-IP MO2) was
approximately 1,250 ml O2 (STPD).day-1 for both species, resulting in air
cell O2 and CO2 tensions of 106 and 40 Torr, respectively. During the 4- to
5-day pipping-to-hatching interval, O2 uptake increases rapidly as
pulmonary respiration is initiated. Hatchling O2 consumption averaged 3,700
ml O2 (STPD).day-1 or about three times the pre-IP MO2. Data support the
hypothesis that embryonic metabolism among Procellariiformes is related to
the extent to which the incubation period deviates from the expected value
based on initial egg mass.
