Genotype by diet interactions in European sea bass (Dicentrarchus labrax L.): Nutritional challenge with totally plant-based diets1

Abstract

Aquaculture of carnivorous species has strongly relied on fish meal and fish oil for feed formulation; however, greater replacement by terrestrial plant-based products is occurring now. This rapid change in dietary environment has been a major revolution and has to be taken into consideration in breeding programs. The present study analyzes potential consequences of this nutritional tendency for selective breeding by estimating genetic parameters of BW and growth rates estimated by the thermal growth coefficient (TGC) over different periods with extremely different diets. European sea bass (Dicentrarchus labrax L.) from a factorial cross (1,526 fish) between 25 sires and 9 dams were used to estimate heritabilities and genotype by diet interaction. Starting 87 d after fertilization (2.5 g), one-half of the sea bass were fed a diet containing marine products (M), and the other one-half were fed a totally plant-based (PB) diet (without any fish meal or fish oil). The fish were individually tagged, reared in a recirculated system, and genotyped at 13 microsatellites to rebuild parentage of individuals. Body weight and TGC were measured for 335 d until fish fed the M diet reached 108.3 g of BW. These traits were significantly less in fish fed the PB diet (P<0.05) in the very first stages after the dietary shift, but the difference in TGC between diets rapidly disappeared (P>0.1). Survival was significantly less in fish fed the PB diet (PB=64.7%, M=93.7% after 418 d, P<0.05). This work identified moderate heritabilities (0.18 to 0.46) for BW with both diets and high genetic correlations between diets (0.78 to 0.93), meaning low genotype by diet interactions, although diets were extremely different. Heritabilities of TGC (0.11 to 0.3) were less than for BW as well as genetic correlations between diets (0.43 to 0.64). Using such extremely different diets, predicted BW gains in different scenarios indicated that selecting fish for growth on a marine diet should be the most efficient way to increase growth on plant-based diets, meaning that, in this case, indirect selection should be more efficient than direct selection.

Lysine supplementation of commercial fishmeal-free diet in hybrid striped bassMorone chrysops x M. saxatilisaffects expression of growth-related genes

“…Nevertheless, similar to the work of Overturf & Hardy (2001), which quantified the expression of a major myogenesis playermyosinas a different way of monitoring growth rates in rainbow trout in response to nutritional treatments, we found that there is also a correlation between Lys supplementation of a fishmeal-free diet, indices of fish growth and composition of growth, and the relative expression of myogenin and myostatin, key genes controlling muscling (Robinson & Li 1994;Kolstad et al 2005;Le Boucher et al 2013). For example, the optimum level of Lys supplementation (35.1 g Lys kg À1 diet) predicted by either quadratic or cubic relationships in Rawles et al (2013) also resulted in a higher amount of myogenin expression and an overall lower amount of myostatin expression ( Fig.…”

Effects of Genotype by Environment Interaction on Genetic Gain and Genetic Parameter Estimates in Red Tilapia (Oreochromis spp.)

“…Our estimates of the between-environment genetic correlations were, however, in accordance with those published for a range of different culture environments for harvest weight in Nile tilapia (Eknath et al, 2007; Bentsen et al, 2012; Khaw et al, 2012; Thodesen et al, 2013; Trọng et al, 2013; Thoa et al, 2016). In other farmed aquaculture species, the genetic correlation estimates reported for harvest weight between contrasting environments during grow-out were also very high and close to one, such as in Rainbow trout (Sylvén et al, 1991; Fishback et al, 2002; Kause et al, 2003), Atlantic cod ( Gadus morhua ) (Kolstad et al, 2006), Whitefish ( Coregonus lavaretus ; Quinton et al, 2007), Barramundi (Domingos et al, 2013), European sea bass (Dupont-Nivet et al, 2010; Le Boucher et al, 2013), Pacific white shrimp ( P. vannamei ) (Gitterle et al, 2005) and Oysters ( Crassostrea gigas ) (Swan et al, 2007). On the contrary, a low genetic correlation ( r g = 0.45 ± 0.09) between freshwater and salt water environments has been reported in Nile tilapia by Luan et al (2008).…”

“…Recently, Thodesen et al (2013) reported, in a different population of red tilapia, that the genetic correlation between body weight in freshwater earthen ponds and floating cages was high (0.92 ± 0.06), while that between freshwater earthen ponds and brackish water tanks was low (0.33 ± 0.14). The G × E interaction effect was reported for a range of fish species, including Nile tilapia (Bentsen et al, 2012; Trọng et al, 2013), rainbow trout (Kause et al, 2003), Atlantic cod (Kolstad et al, 2006), Asian and European sea bass (Dupont-Nivet et al, 2010; Domingos et al, 2013; Le Boucher et al, 2013). A synthesis of the literature review across farmed aquaculture species indicates that when the environments are similar (e.g., pond vs. cage), the G × E effect is not of commercial importance for body traits (e.g., Nguyen, 2016; Sae-Lim et al, 2016).…”

Quid de l’utilisation des protéines d’origine végétale en aquaculture ?

“…Dans les aliments pour salmonidés et poissons marins, 80 à 95 % de la farine de poisson peut ainsi être substituée sans impact négatif. Mais le remplacement total de la farine de poisson par des produits végétaux provoque une diminution du taux de croissance et de l'efficacité alimentaire chez les espèces de haut niveau trophique, même si tous les éléments nutritifs nécessaires sont présents dans l'aliment (Gómez-Requeni et al, 2004 ;Vilhelmsson et al, 2004 ;Panserat et al, 2008 ;Dupont-Nivet et al, 2009 ;Alami-Durante et al, 2010 ;Le Boucher et al, 2012, 2013a.…”