QTL for body weight, morphometric traits and stress response in European sea bass Dicentrarchus labrax

Abstract

Natural mating and mass spawning in the European sea bass (Dicentrarchus labrax L., Moronidae, Teleostei) complicate genetic studies and the implementation of selective breeding schemes. We utilized a two-step experimental design for detecting QTL in mass-spawning species: 2122 offspring from natural mating between 57 parents (22 males, 34 females and one missing) phenotyped for body weight, eight morphometric traits and cortisol levels, had been previously assigned to parents based on genotypes of 31 DNA microsatellite markers. Five large full-sib families (five sires and two dams) were selected from the offspring (570 animals), which were genotyped with 67 additional markers. A new genetic map was compiled, specific to our population, but based on the previously published map. QTL mapping was performed with two methods: half-sib regression analysis (paternal and maternal) and variance component analysis accounting for all family relationships. Two significant QTL were found for body weight on linkage group 4 and 6, six significant QTL for morphometric traits on linkage groups 1B, 4, 6, 7, 15 and 23 and three suggestive QTL for stress response on linkage groups 3, 14 and 23. The QTL explained between 8% and 38% of phenotypic variance. The results are the first step towards identifying genes involved in economically important traits like body weight and stress response in European sea bass.

Quantitative trait loci for morphometric traits in multiple families of common carp (Cyprinus carpio)

“…The moderate to high heritabilities for morphometric traits indicated that additive genetic variation exists in those traits and it is potentially feasible to conduct genetic improvement and achieve expected breeding goals in common carp. Additionally, these heritability estimates of morphometric traits were similar to the results of other species, which generally ranged from 0.04 to 0.42 (Chatziplis et al, 2007) and 0.52 to 0.68 (Massault et al, 2010) for European sea bass, and 0.24 to 0.57 for gilthead seabream (Boulton et al, 2011).…”

“…For the time being, limited information is available on the inheritance of morphological traits in fish. Genetic studies aiming to identify loci controlling morphological variation have been carried out in three-spine stickleback (Gasterosteus aculeatus) (Liu et al, 2014;Yang et al, 2016), Whitefish (Coregonus clupeaformis) (Laporte et al, 2015), gilthead seabream (Sparus aurata) (Boulton et al, 2011;Loukovitis et al, 2013), and European sea bass (Dicentrarchus labrax) (Chatziplis et al, 2007;Massault et al, 2010). However, QTL mapping relating to the morphological performance of common carp only involved standard length (SL), body height (BH), head length, tail length and so on Laghari et al, 2014b;Lu et al, 2015).…”

Conclusions: Aquaculture and Behaviour

“…The use of genetic technologies in aquaculture to date has concentrated on morphological, physiological and life history traits, but in principle there is no reason why they should not be applied to morphological and physiological traits closely related to behaviour (stress responsiveness, for example; Massault et al 2010) and for behavioural traits of importance (aggression, for example).…”

Detection of QTL associated with three skeletal deformities in gilthead seabream (Sparus aurata L.): Lordosis, vertebral fusion and jaw abnormality

“…In gilthead seabream, QTL for traits of commercial interest have been detected by using microsatellite markers: several QTL related with growth, sex determination and several morphometric traits were found by Loukovitis et al (2011Loukovitis et al ( , 2012Loukovitis et al ( , 2013, two QTL for resistance to pasteurellosis were found by Massault et al (2010) and one significant QTL for morphometric traits and two suggestive QTL for stress response to confinement were detected by Boulton et al (2011). However, no QTL for frequent vertebral column deformities have been reported.…”