Production of antifreeze glycoproteins in cultured and wild juvenile Atlantic cod (Gadus morhua L.) in a common laboratory environment

Many fishes accumulate antifreeze proteins or antifreeze glycoproteins (AFG Ps) in the blood to increase their chances of survival in cold seawater. Co d (Gadus morhua L.) from colder environments have been found to produce mor e AFGPs than those from warmer areas, but the genetic and environmental con tributions to this variation have not been determined. Populations of cultu red (from the Grand Banks; Gulf of Maine) and wild (from Fortune Bay; Bonav ista Bay) juvenile cod were kept in a common laboratory environment to inve stigate differences in AFGP production. All the populations were capable of producing AFGPs, and the AFGP levels were similar in cultured and wild cod . The results indicate that high temperatures associated with the productio n of cultured cod do not negatively affect the ability to produce AFGPs. In addition, young cod from as far south as the Gulf of Maine are capable of producing AFGPs at levels similar to those from the northeast coast of Newf oundland.