Genetic Analysis of the Fatty Acid Profile in Gilthead Seabream (Sparus aurata L.)

Abstract

The gilthead seabream is one of the most valuable species in the Mediterranean basin both for fisheries and aquaculture. Marine fish, such as gilthead seabream, are a source of n3 polyunsaturated fatty acids, highly appreciated for human food owing to their benefits on the cardiovascular and immune systems. The aim of the present study was to estimate heritability for fatty acid (FA) profile in fillet gilthead seabream to be considered as a strategy of a selective breeding program. Total of 399 fish, from a broodstock Mediterranean Sea, were analysed for growth, flesh composition and FA profile. Heritabilities for growth traits, and flesh composition (fat, protein, and moisture content) were medium. Heritability was moderate for 14:0, 16:0 and 18:1n9 and for sum of monounsaturated FA and n6/n3 ratio, and it was low for 20:1n11 and 22:6n3 and the ratio unsaturated/saturated FA. Breeding programs in gilthead seabream usually include growth as the first criterion in the selection process of the fish. However, other quality traits, such as fillet fat content and its fatty acids profile should be considered, since they are very important traits for the consumer, from a nutritional point of view and the benefits for the health.

Genetic Parameters and Genotype × Diet Interaction for Body Weight Performance and Fat in Gilthead Seabream

“…The heritability estimates using the multivariate animal model in the literature for gilthead seabream body weight at 130, 165 and 509 DPH were 0.28, 0.32 and 0.34, respectively [25]. At an older age, at 689-690 DPH the heritability estimates of the body weight were 0.25 or 0.29 [26,27]; similarly, at 980 DPH, the heritability estimate was 0.24 [28]. However, Gulzar et al [29], estimated the heritability of the harvest weight (approximately 400 g) equal to 0.37 in a Greek farm (Galaxidi, Greece) and 0.55 in a farm in Spain.…”

Fatty acid profiles of cultured Hippocampus hippocampus trunk muscles and potential nutritional value

“…A high content of n-3 PUFA in the muscles from males and females results in an n-6/n-3 ratio lower than 1, highlighting the nutritional potential of H. hippocampus (Table 1). Although it has been suggested a minimum n-6/n-3 ratio of 1:1 for balanced diets, since modern human diets are rich in n-6 PUFA, which increases the probability of developing health disorders, such as cardiovascular, inflammatory, and autoimmune diseases (Simopoulos, 2002;Scaioli et al, 2017), an increase in n-3 PUFA consumption will contribute to balance the n-6/n-3 ratio towards a healthier diet (Vallecillos et al, 2021). The trunk muscles from H. hippocampus, which, to our best knowledge, had not yet been described in terms of the FA profile, presented higher absolute compositions of SFA in both sex groups (Table 1).…”

“…The trunk muscles from H. hippocampus, which, to our best knowledge, had not yet been described in terms of the FA profile, presented higher absolute compositions of SFA in both sex groups (Table 1). While diet influences the FA composition of the fillets in cultured fish (Vallecillos et al, 2021), Ballester-Lozano et al (2011) highlight that one must also account for the lipid content of the fillet (neutral and polar fractions), as this is also a source of variability in FA profiles. Triacylglycerols (TAG) are rich in MUFA and SFA, while polar lipids present a high proportion of PUFA (Cowey and Sargent, 1977;Rey et al, 2018;Sushchik et al, 2020;Vallecillos et al, 2021).…”

“…While diet influences the FA composition of the fillets in cultured fish (Vallecillos et al, 2021), Ballester-Lozano et al (2011) highlight that one must also account for the lipid content of the fillet (neutral and polar fractions), as this is also a source of variability in FA profiles. Triacylglycerols (TAG) are rich in MUFA and SFA, while polar lipids present a high proportion of PUFA (Cowey and Sargent, 1977;Rey et al, 2018;Sushchik et al, 2020;Vallecillos et al, 2021). An increase in fillet lipid content is related to an increase in fat deposits, usually rich in TAG, resulting in higher MUFA and lower PUFA relative abundances (%TFA) (Ballester-Lozano et al, 2011;Vallecillos et al, 2021).…”

Enhancing the nutritional values of farmed fish production systems

“…In order to reduce aquaculture's reliance on fish oils, feed manufacturers try to replace fish and fish oil in diets with plant‐based oils. Because replacement of fish oils in aquafeeds with plant‐based oils can lead to decreased levels of omega‐3s in farmed fish, 9 improving fish' natural ability to convert the fatty acids in plants to the beneficial omega‐3s would produce a more nutritious product. Similarly, fish with low omega‐3/omega‐6 ratios, particularly freshwater fish, could be made more nutritious by genetically increasing omega‐3 levels.…”