High antifreeze protein levels in wolffish (Anarhichas lupus) make them an ideal candidate for culture in cold, potentially ice laden waters

This study was designed to determine whether juvenile Atlantic wolffish (Anarhichas lupus) cultured at optimal temperatures for growth (9-12 degrees C were fully capable of producing high concentrations of plasma AFP when exposed to the low water temperatures. A twelve month cycle of plasma AFP activity was examined in juvenile wolffish (1(+)and 2(+)) initially raised in heated water and then exposed to either a constant regimen of warm water or a seasonal cycle of water temperatures. The results indicate that juvenile wolffish exposed to a seasonal cycle of water temperatures produced high levels (approximately 12 mg/ml) of AFP when the temperatures declined to low levels. Moreover, the levels of antifreeze found in juveniles were similar to those observed in adult wolffish. Wolffish kept in warm-water conditions produced little or no AFP. It appears that the thermal regimen can be manipulated to enhance growth rates without compromising the ability to produce AFP and thus tolerance to sub-zero temperatures. On-growing of the juveniles under warm water temperatures conditions will not reduce the yield of AFP that can be obtained at harvest. (c) 2007 Elsevier B.V. All rights reserved.