Produção Nacional
The effect of inspired oxygen tension on oxygen uptake and tolerance to anoxia in the water snakes Helicops modestus and Liophis miliaris (Colubridae)
1980; Elsevier BV; Volume: 65; Issue: 4 Linguagem: Inglês
10.1016/0300-9629(80)90059-6
ISSN0300-9629
AutoresAugusto S. Abe, Erasmo Garcia Mendes,
Tópico(s)Fish biology, ecology, and behavior
Resumo1. The effect of oxygen tension, po2, on oxygen uptake and tolerance to anoxia have been studied by exposure in nitrogen atmosphere and diving in the water snakes Helicops modestus and Liophis miliaris, at 25°C. 2. The critical Po2, was the same (70mmHg O2) for both species, but below that tension H. modestus showed a higher degree of dependence on Po2. 3. Anoxia tolerance time was longer (14 min for H. modestus and 4 min for L. miliaris) during forced dive than during exposure to a 100% nitrogen atmosphere. No difference was found in pre- and post-forced dive oxygen uptake values in both species. 4. The maximum duration of a voluntary dive was shorter than the mean tolerance time to forced dives in L. miliaris. but longer in H. modestus. 5. H. modestus, the more aquatic species, is significantly more tolerant of complete anoxia (100% N2 exposure) and submersion.
Referência(s)