Study documents long-term progress in seabream breeding

The research is based on production and pedigree data from nearly 124,000 fish representing 1,843 families produced between 2002 and 2023. The breeding programme achieved a cumulative 76% genetic gain in harvest weight, equivalent to around 15% per generation (3.6% annually), while maintaining low levels of inbreeding and preserving genetic diversity.

The study was conducted by Benchmark Genetics in collaboration with AVRAMAR and is based on one of the Mediterranean's longest-running commercial seabream breeding programmes.

According to the researchers, improved growth rates can shorten production cycles, improve resource efficiency and strengthen the long-term sustainability and competitiveness of aquaculture. While this study focused on harvest weight, the breeding programme has also applied multi-trait selection to improve characteristics such as robustness, survival and product quality.

"Long-term datasets of this quality are exceptionally rare in aquaculture," said Ingunn Thorland, Senior Geneticist at Benchmark Genetics and lead author of the study. "This study demonstrates that well-designed breeding programmes can deliver sustained genetic improvement over decades while maintaining the genetic diversity needed for future progress."

Nikos Katribouzas, Group Genetics & R&D Manager at AVRAMAR, said the results reflect more than 20 years of continuous development of the breeding programme.

"The documented genetic gains confirm the value of long-term investment in selective breeding and provide a strong foundation for the continued development of the programme."

The researchers say the findings provide one of the clearest examples to date of realised genetic gain achieved under commercial farming conditions and highlight the potential for further progress through the integration of genomic technologies into breeding programmes.