Cobia, Rachycentron canadum, is a fast-growing marine fish species with great potential for the commercial aquaculture industry; previous studies indicated sexual dimorphism, with females reported to grow faster/bigger than males. This study, conducted by Open Blue’s R&D department and partly funded by SENACYT (Panama government science & technology secretary), focuses as primary objective on characterizing the growth performance and finished product yield of monosex Cobia (Rachycentron canadum) in a commercial aquaculture impact setting.
The study involved a 12-month controlled trial in which Cobia was raised under standardized culture conditions. PCR was employed for precise sex determination, followed by the division of groups into triplicate tanks with all-female, all-male, and 50/50 mixed populations.
Subsequently, a 15-day acclimation phase was implemented, and tanks were subjected to routine sampling every four weeks, commencing at an initial a verage b ody weight (ABW) of 493.7g, and continuing until they reached the target harvest size range for cobia (3-4kg ABW). Data on average body weight (ABW), FCR, and SGR were calculated following sampling at regular intervals, and finished product yield, including fillet quality and quantity, was evaluated.
Results indicated significant differences in ABW, FCR, and SGR between female monosex, and male monosex Cobia , favoring females, starting from the fifth month (2.13kg vs 1.86kg). These differences were maintained over time and were accentuated upon reaching the ninth month, showing significant differences between all groups at the end of the trial (3.94kg all-females, 3.49kg mixed group, 2.86kg all-males).
Female monosex Cobia exhibited improved growth rates and feed efficiency, suggesting cost-effective aquaculture potential.
In conclusion, this study demonstrates an enhanced growth in monosex all-female Cobia groups and suggest high-impact cost reduction benefits associated to all-female monosex Cobia in commercial aquaculture.