QTL for Stress and Disease Resistance in European Sea Bass, <i>Dicentrarhus labrax</i> L.
Dimitrios Chatziplis,
Stavroula Oikonomou,
Dimitrios Loukovitis,
Dimitrios Tsiokos,
Athanasios Samaras,
Arkadios Dimitroglou,
Lefteris Kottaras,
Kantham Papanna,
Leonidas Papaharisis,
Costas Tsigenopoulos,
Michail Pavlidis
Affiliations
Dimitrios Chatziplis
Laboratory of Agrobiotechnology and Inspection of Agricultural Products, Dept of Agricultural Technology, School of Geotechnical Sciences, International Hellenic University, Alexander Campus, P.O. Box 141, 57 400 Sindos, Thessaloniki, Greece
Stavroula Oikonomou
Laboratory of Agrobiotechnology and Inspection of Agricultural Products, Dept of Agricultural Technology, School of Geotechnical Sciences, International Hellenic University, Alexander Campus, P.O. Box 141, 57 400 Sindos, Thessaloniki, Greece
Dimitrios Loukovitis
Research Institute of Animal Science, ELGO Demeter, 58100 Paralimni, Giannitsa, Greece
Dimitrios Tsiokos
Research Institute of Animal Science, ELGO Demeter, 58100 Paralimni, Giannitsa, Greece
Athanasios Samaras
Department of Biology, University of Crete, GR-714 09 Heraklion, Greece
Arkadios Dimitroglou
Department of Research & Development, Nireus Aquaculture SA, 341 00 Chalkida, Greece
Lefteris Kottaras
Department of Research & Development, Nireus Aquaculture SA, 341 00 Chalkida, Greece
Kantham Papanna
Department of Research & Development, Nireus Aquaculture SA, 341 00 Chalkida, Greece
Leonidas Papaharisis
Department of Research & Development, Nireus Aquaculture SA, 341 00 Chalkida, Greece
Costas Tsigenopoulos
Institute of Marine Biology, Biotechnology and Aquaculture (IMBBC), Hellenic Centre for Marine Research (HCMR), 71003 Heraklion, Crete, Greece
Michail Pavlidis
Department of Biology, University of Crete, GR-714 09 Heraklion, Greece
There is a growing interest in selective breeding in European sea bass (Dicentrarchus labrax), especially regarding family selection based on growth performance. In particular, quantitative trait loci (QTL) identification in sea bass enhances the application of marker-assisted breeding for the genetic improvement of the production traits. The aims of the study were to identify potential QTL affecting stress and immunological indicators, body weight, and mortality after vibriosis injection in sea bass as well as to estimate heritability and genetic/phenotypic correlations for the aforementioned traits. To this end, stress test was performed on 960 offspring and a sub-group of them (420) was selected to explore the mortality after vibrio injection. Selective genotyping was performed in 620 offspring for 35 microsatellite markers and distributed into 6 linkage groups. The length of the genetic linkage map was 283.6 cM and the mean distance between the markers was 8.1 cM. QTL affecting body weight in three different growth periods detected on linkage groups LG1, LG4, LG6, and LG14. A QTL associated with weight in early growth stages (290–306 days post-hatching) was also identified on LG3. QTL analysis confirmed the existence of QTL affecting cortisol levels, on LG3 and LG14. Moreover, new QTL affecting only cortisol and glucose levels were detected on LG1 and LG23. No QTL affecting hormonal or biochemical marks was found on LG4 and LG6. Heritability of cortisol, lysozyme levels, and mortality were high (0.36, 0.55, and 0.38, respectively).
