Gonadal development of triploid Atlantic Cod Gadus morhua

During their third and fourth years of life, triploid Atlantic cod Gadus morhua females exhibited diminished ovarian development at both macroscopic and microscopic levels, with significantly lower gonado-somatic indices (I-G) and higher carcass yields (Y-C) than diploid females during spawning periods. In contrast, diploid and triploid testes were indistinguishable through macroscopic and histological assessment. No significant differences were found in male I-G or Y-C in relation to ploidy, with the exception of a higher Y-C for triploids during the first of the two monitored spawning seasons. As a result of suppressed oogenesis, triploid female G. morhua, but not triploid males, can be used to eliminate sexual maturation in this species and advance the development of the G. morhua aquaculture industry. (C) 2011 The Authors Journal of Fish Biology (C) 2011 The Fisheries Society of the British Isles