Gas Supersaturation in Fisheries: Causes, Concerns, and Cures,
Abstract
Gas embolisms in fishes have been recognized as a problem since at least 1670, and the term 'super-saturation', was used as early as 1866 to describe an excess of any gas in solution. Studies carried out near the turn of the century suggested that fish culturists understood some of the problems involved in 'gas bubble disease,' and knew how to apply certain preventive techniques. Gas bubble disease was first described by Gorham (1901) as consisting of 'vesicles of gas invading all the superficial parts of the fish, especially fins, eyeballs, and in loose connective tissue of the orbits, so that the eyes were forced from their sockets; less commonly bubbles formed beneath the lining of the mouth, in the gill arches, or beneath the skin, so that scales were raised from the surface. The swimming behavior of the fish was disturbed, especially in maintenance of horizontal equilibrium.' Gorham was perhaps the first investigator to relate gas bubble disease problems to a reduction in partial pressures rather than to a pathogen. He calculated that, in a fish raised from a depth of 300 fathoms to the surface, the contained gases expanded to more than 54 times the original volume. He noted that fish taken from great depths were usually dead when they reached the surface, the eyes were protruded, the air bladder was greatly distended or ruptured, and the gastrointestinal tract was often everted from the mouth or anus. In fish less severely affected by supersaturated water, reentry into deep water alleviated the problem because both pressure and gas solubility increase with depth.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1987
- Accession Number
- ADA322709
Entities
People
- Leif L. Marking