Histological development of the terminal airways in pinniped and sea otter lungs

A histological study by light microscopy on the development of the terminal airways in fetal lungs of the harbor seal (Phoca vitulina), northern sea lion (Eumetopias jubatus), and sea otter (Enhydra lutris) showed the development of muscle and cartilaginous rings to occur late in gestation. At term...

Full description

Bibliographic Details
Published in:Canadian Journal of Zoology
Main Authors: Drabek, Charles M., Kooyman, Gerald L.
Format: Article in Journal/Newspaper
Language:English
Published: Canadian Science Publishing 1984
Subjects:
Online Access:http://dx.doi.org/10.1139/z84-016
http://www.nrcresearchpress.com/doi/pdf/10.1139/z84-016
Description
Summary:A histological study by light microscopy on the development of the terminal airways in fetal lungs of the harbor seal (Phoca vitulina), northern sea lion (Eumetopias jubatus), and sea otter (Enhydra lutris) showed the development of muscle and cartilaginous rings to occur late in gestation. At term they were still much less developed than in the terminal airways seen in adults. The most extensive reinforcement with cartilage of the terminal airways was observed in the sea lion lungs and the least in the seal lungs. The fetal lung development was contrasted with that of the porpoise. We conclude that unlike the porpoise, much further development of the terminal airways in pinnipeds and sea otters occurs during the neonatal stage when the animal is nondiving in a "terrestrial" environment.