RESPONSES TO CHRONIC HYPOXIA IN EMBRYONIC ALLIGATORS

To investigate developmental responses to chronic hypoxia, we incubate d alligator eggs at 17% O-2 and 21% O-2 for the entire course of embry onic development and for 5 months post-hatching. Hypoxic-incubated all igators hatched later and at a smaller size. Hematocrit was significan tly higher in hypoxic-incubated animals immediately post-hatch. Allost eric modification of hemoglobin oxygen affinity did not appear to play a role in the adaptation to hypoxia, given equal nucleotide triphosph ate-to-hemoglobin ratios in the hypoxic and normoxic groups. When acut ely exposed to 21% O-2, hypoxic-incubated alligators maintained oxygen consumption relative to their normoxic siblings despite their lower m ass. (C) 1995 Wiley-Liss, Inc.