Genetic variation for carcass quality traits in cultured sea bass (Dicentrarchus labrax)

Abstract

-Genetic parameters for carcass quality traits were estimated in 27 families of sea bass (3 dams × 9 sires factorial mating design), raised mixed in the same tanks starting before hatching. Offspring parentage was determined a posteriori using 6 microsatellite loci. Carcass quality traits were recorded at 818 days post fertilization (mean standard length: 32.6 ± 3.1 cm). Genetic parameters were estimated from the sire half sib variance and covariance components. Heritability of body weight (BW) and carcass processing traits (standardized to body weight) percent head weight (Head%), percent viscera weight (Viscera%) and percent visceral fat weight (VisceFat%) were relatively high ranging from 0.48 ± 0.15 (Viscera%) to 0.87 ± 0.23 (Head%); the estimate of heritability for fillet yield (Fillet%) was lower (0.25 ± 0.10) but was significantly greater than zero. Body weight was positively correlated to Fillet%, Viscera%, and VisceFat%, and negatively correlated to Head%. These results indicate that these carcass processing traits can be modified by directional selection and that selection for greater BW would lead to an increase of Fillet%, Viscera% and VisceFat% and a decrease of Head%. Muscle lipid content (MuscleLipid%) was determined using two indirect methods: measurements with a Torry Fish Fatmeter (TorryLipid) and determination of the percentage of dry matter content (MuscleDry%) via desiccation. Both measures were highly correlated to chemical measurements of MuscleLipid%. Regression analysis indicated a superior predictive value of TorryLipid suggesting that MuscleLipid% may be evaluated via rapid, non lethal measurements with a Torry Fish Fatmeter. Heritability estimates of TorryLipid and MuscleDry% differed significantly from zero (TorryLipid: 0.28± 0.12, MuscleDry%: 0.36± 0.14) indicating that MuscleLipid% could be lowered by directional selection. TorryLipid and MuscleDry% were weakly correlated to body weight and carcass processing traits suggesting that simultaneous improvement of MuscleLipid% and other carcass quality traits may require definition of multi-trait selection indices.

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

“…marker assisted selection. From such communally bred families, quantitative genetic parameters have been reported for heritabilities and phenotypic and genotypic correlations for some traits, such as sex (Vandeputte et al 2007), body weight and length (Vandeputte & Launey 2004;Saillant et al 2006;Chatziplis et al 2007) and carcass traits (Saillant et al 2009). From such communally bred families, quantitative genetic parameters have been reported for heritabilities and phenotypic and genotypic correlations for some traits, such as sex (Vandeputte et al 2007), body weight and length (Vandeputte & Launey 2004;Saillant et al 2006;Chatziplis et al 2007) and carcass traits (Saillant et al 2009).…”

“…Large scale profiling of paternity with microsatellite markers has facilitated the breeding of families on an experimental and commercial scale in a reliable and affordable fashion (García de Léon et al 1995;Chatziplis et al 2007). From such communally bred families, quantitative genetic parameters have been reported for heritabilities and phenotypic and genotypic correlations for some traits, such as sex (Vandeputte et al 2007), body weight and length (Vandeputte & Launey 2004;Saillant et al 2006;Chatziplis et al 2007) and carcass traits (Saillant et al 2009). Heritabilities for growth are relatively high and vary from 0.29 to 0.60 in European sea bass (Saillant et al 2006;Dupont-Nivet et al 2008).…”

A first insight into genotype × diet interactions in European sea bass (Dicentrarchus labrax L. 1756) in the context of plant-based diet use

“…Known as a valuable trait in this species, fat deposition is known to be affected by dietary carbohydrate levels as well as protein sources (Dias et al 2005). Saillant, Dupont‐Nivet, Sabourault, Haffray, Laureau, Vidal and Chatain (2009) demonstrated that the quality of prediction of lipid content with Distell Fish Fatmeter, previously used on rainbow trout (Douirin, Haffray, Vallet & Fauconneau 1998; Quillet, Le Guillou, Aubin & Fauconneau 2005; Quillet, Le Guillou, Aubin, Labbé, Fauconneau & Médale 2007), was accurate enough to assess genetic parameters in sea bass, with a moderate heritability (0.28 ± 0.12) for this trait. We measured and followed this trait during our trial.…”

Condition Indices as Surrogates of Energy Density and Lipid Content in Juveniles of Three Fish Species

“…The fatmeter measures the water content of the tissues beneath the skin, which relates to the amount of lipid stored in subdermal reserves and associated peripheral muscle tissues (hereafter, subdermal lipids). For many species, measures of subdermal lipid content from the fatmeter are well correlated with wholefish or fillet lipid content measured by proximate composition analysis (0.58 ≤ r 2 ≤ 0.87; Vogt et al 2002;Hendry and Beall 2004;Bransden et al 2007;Kaga et al 2009;Saillant et al 2009;Van Sang et al 2009;Caldwell et al 2013;Mesa and Rose 2015), but these relationships have often been developed for adult fish only, and the species investigated thus far are those that are likely to accumulate large lipid stores as adults.…”