The development of the swim bladder of the Atlantic salmon

✍ Scribed by William S. Hoar

• Book ID: 102903387
• Publisher: John Wiley and Sons
• Year: 1937
• Tongue: English
• Weight: 633 KB
• Volume: 61
• Category: Article
• ISSN: 0362-2525
• DOI: 10.1002/jmor.1050610205

✦ Synopsis

Abstract

The anlage of the swim bladder of the Atlantic salmon arises as a small mass of undifferentiated cells resting dorso‐laterally on the posterior wall of the fore‐gut. This mound of cells is proliferated from the narrow band of mesoderm which lies between the epithelium and the serosa of the alimentary canal. The concentration thus formed elongates slowly for 11 weeks. At the end of this time an evagination from the lumen of the right side of the oesophagus grows into it. This tube commences to elongate rapidly just previous to the time of hatching, and reaches the posterior end of the body cavity at approximately the time when the young salmon emerge from the gravel. Throughout the fresh water life of the fish this organ is a relatively large thin walled sac, lying dorsal to the body cavity. Microscopic examination reveals layers typical of those of the digestive tract.