Optimised nutrition and egg quality in Atlantic cod broodstock

Broodstock management and nutrition is the basis for further production. A great concern for the industry is the possibility of impoverishment of the broodstock over time due to suboptimal nutrition. As cod broodstocks generally are kept and utilised for egg production over several consecutive spawning seasons, even a relatively slight imbalance in diet composition may lead to broodstocks of bad condition, and even to mortalities, after a few years in captivity. Poor broodstock health and condition may al so result in eggs and larvae with strongly reduced quality. Optimal nutrition is especially critical for photo-manipulated broodstock, which will need time and resources to adapt to the new regime. The present project is a collaboration between the three major cod hatcheries Cod Culture Norway (CCN), Troms Marin Yngel (TMY) and Grieg Marine Farms (GMF) (together representing about 30% of present production capacity for cod juveniles in Norway), and NIFES, Institute of Marine Research and Nutreco ARC. The project objectives will be achieved partly through scientifically designed feeding trials carried at Institute of Marine Research Austevoll and partly through analyses of samples and data collected at the commercial hatcheries. In addition to classical m ethods for analysis of spawning success, the project will also include hormone analysis and gene expression studies. Expected results from the project are: · Better understanding of mechanisms regulating reproduction in Atlantic cod and in fish in general , and on the role essential fatty acids play in this respect · Identification of nutritional factors which over time may become limiting for reproductive performance in farmed cod · Standard methods for sampling and evaluation of spawning success, and im plementation of these in the industry · Advice on temperature regime for (off-season) cod broodstock