Unraveling turbot (Scophthalmus maximus) resistance to Aeromonas salmonicida: transcriptomic insights from two full-sibling families with divergent susceptibility

Furunculosis, caused by the Gram-negative bacterium Aeromonas salmonicida subsp. salmonicida, remains a significant threat to turbot (Scophthalmus maximus) aquaculture. Identifying genetic backgrounds with enhanced disease resistance is critical for improving aquaculture health management, reducing antibiotic dependency, and mitigating economic losses. Therefore, uncovering the factors involved in resistance to this disease is a cornerstone in aquaculture. In this study, we identified full-sibling turbot families showing significantly different resistance levels to A. salmonicida. We conducted RNA-Seq analyses on both a resistant and a susceptible family, examining uninfected and 24 hours post-infection samples from head kidney and liver tissues. This represents the first RNA-Seq analysis comparing resistant and susceptible turbot families and provides valuable insights for developing selective breeding programs aimed at enhancing disease resistance in turbot and other aquaculture species susceptible to A. salmonicida.