Fatty acid partitioning varies across fillet regions during sexual maturation in female rainbow trout (Oncorhynchus mykiss)

Rainbow trout (Oncorhynchus mykiss) are commonly reared as diploids (2N, two sets of chromosomes) or triploids (3N, three sets of chromosomes). Sexual maturation in 2N has negative effects on production efficiency, nutrient retention, and fillet quality. On the other hand, 3N female rainbow trout fail to develop gonads, thus enabling an efficient extended growth period when production of larger fillets is desired. The objective of this study was to determine how fatty acid (FA) profiles of various tissue types change throughout development in 2N and 3N rainbow trout, with an emphasis on the response of different fillet regions. Diploid and 3N female rainbow trout were comingled and harvested at 10, 18, and 22 months post hatch (mph) and FA profiles of the viscera, fillet sections, and fillet trimmings were analyzed. Diploid fish were larger (P