Mechanisms of Freeze Avoidance in Eggs of the Antarctic Naked Dragonfish (Gymnodraco acuticeps) and Atlantic Tomcod (Microgadus tomcod)

• Main Author: Carlson, Jeremy M.
• Format: Text
• Language: unknown
• Published: The Keep 2013
• Subjects: Antarctic Naked Dragonfish; fish eggs; Gymnodraco acuticeps; Atlantic Tomcod; Microgadus tomcod; Animal Sciences; Aquaculture and Fisheries; Biology; Life Sciences; Antarctic; Newfoundland; The Antarctic; McMurdo Sound; Antarctic Ocean; Antarc*; North Atlantic
• Online Access: https://thekeep.eiu.edu/bio_students/1; https://thekeep.eiu.edu/cgi/viewcontent.cgi?article=1000&context=bio_students

A remarkable number of marine teleosts belonging to the perciform suborder Notothenioidei and the paracanthopterygian suborder Gadoidei (cods and their allies) have evolved biophysical and physiological adaptations that promote freeze avoidance to temperatures as low as 1oC below the equilibrium freezing point of their body fluids (Cheng et al. 2003; Costanzo et al. 1995; Howes 1991; Raymond and DeVries 1977). Among the Notothenioids endemic to the Antarctic Ocean, the naked dragonfish (Gymnodraco acuticeps, Figure 1) inhabits the ice-laden waters near McMurdo Sound where the annual water temperature remains stable at -1.87 ± 0.1oC (Komatsu et al. 1970; Bargelloni et al. 1994). In the north Atlantic region, fish fauna along the coastal waters from southern Labrador and northern Newfoundland to Virginia include the Atlantic tomcod (Microgadus tomcod, Figure 2) which is primarily found in shallow, low-salinity estuaries and brackish or freshwater river mouths where water temperatures reach -1.2oC during winter seasons (Pearcy and Richards 1962).