Comparative study of lipids and fatty acids in the liver, muscle, and eggs of wild and captive common snook broodstock

Abstract

In this study, the lipid composition of wild and captive common snook broodstock were investigated to identify potential nutritional deficiencies and formulate suitable diets for captive stocks. Results showed captive snook incorporated significantly more lipid than their wild counterparts. However, cholesterol and arachidonic acid (ARA) levels were significantly lower compared to wild fish, which may impact steroid and prostaglandin production, reproductive behavior and gametogenesis. In eggs obtained from captive broodstock, high docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) levels, associated with low ARA contents were found. As a result, ARA/EPA ratio in captive eggs was less than half of that in wild eggs with the potential for negative consequences on embryo and larval development. In conclusion, large differences were noticed between wild and captive broodstock that may contribute to the reproductive dysfunctions observed in captive snook broodstock (e.g. incomplete oocyte maturation, low milt production and highly variable egg and larval quality). The wild snook survey also identified the presence of hydrocarbons in the liver, which should be further studied to identify a potential impact on the reproductive performances of a vulnerable population like common snook.

Characterizing egg quality and larval performance from captive mahi-mahiCoryphaena hippurus(Linnaeus, 1758) spawns over time

“…EPA is known to be a potent inhibitor AA‐derived metabolic pathways such as the production of eicosanoids which earlier stated are crucial for steroid production to be used in endocrine, hypothalamic, immune and reproductive functions (Rainuzzo et al., ; Tocher, ). Lower absolute levels of AA as well as a higher ratio of EPA/AA as reported in this study have been associated with lower larval survival and reproductive dysfunction in captive broodstock as shown in Pacific olive flounder Paralichthys olivaceus (Temminck and Schlegel, 1846; Furuita et al., ), white sea bream (Cejas et al., , ), common sole (Lund et al., ), Senegalese sole (Norambuena et al., ), greater amberjack (Rodríguez‐Barreto et al., ) and common snook (Hauville et al., ). The results suggest that elevated levels of EPA and higher ratio of EPA/AA did not affect the larval survival over time.…”

“…Improper broodstock nutrition can lead to poor and infrequent spawns, reproductive dysfunction of broodstock in captivity and overall poor egg quality. (Brooks, Tyler & Sumpter, ; Hauville et al., ; Lund, Steenfeldt & Hansen, ; Rainuzzo, Reitan & Olsen, ; Tocher, ). Good egg quality is strongly influenced by the maternal broodstock diet which is imparted into the developing oocytes through the process of vitellogenesis (Brooks et al., ; Tocher, ).…”

“…In assessing egg quality in the broodstock of any marine finfish, comparing eggs and related tissues from wild and captive broodstock can identify any nutritional deficiencies that may be present in the diet which could be implemented into ameliorating limitations in egg production (Hauville et al., ; Migaud et al., ). This has been well demonstrated in previous literature with Atlantic cod Gadus morhua (Linnaeus, 1758; Kjørsvik, ), striped bass Morone saxatilis (Walbaum, 1792; Harrell & Woods, ), striped trumpeter Latris lineata (Bloch and Schneider, 1801; Morehead, Hart, Dunstan, Brown & Pankhurst, ), white seabream Diplodus sargus (Linnaeus, 1758; Cejas et al., , ), common sole Solea solea (Linnaeus, 1758; Lund, Steenfeldt, Suhr & Hansen, ), Senegalese sole Solea senegalensis (Kaup, 1858; Norambuena, Estevez, Bell, Carazo & Duncan, ) and common snook Centropomus undecimalis (Bloch, 1792; Hauville et al., ) yet the literature is very limited on identifying these deficiencies in high‐performance pelagic species with notable exceptions including studies on Atlantic bonito Sarda sarda (Bloch, 1793; Ortega & Mourente, ), Atlantic bluefin tuna Thunnus thynnus (Linnaeus, 1758; Ortega & Mourente, ; Pousis et al., ), lesser amberjack Seriola rivoliana (Valenciennes, 1833; Saito, ) and greater amberjack Seriola dumerili (A. Risso, 1810; Rodríguez‐Barreto et al., ; Saito, ).…”

Fatty acids in an iteroparous fish: variable complexity, identity, and phenotypic correlates

“…We observed positive correlations between fatty acid complexity of individual females and the quality eggs they produced, as determined by egg size, lipid content, and egg size variability, suggesting that females with more complex fatty acid profiles produced higher-quality eggs. Higher numbers or evenness of fatty acids may signify a diverse reserve of lipids to use during the energetically expensive production of eggs, allowing females to preferentially mobilize long chain PUFA for somatic use while allocating C 18 and short chain monounsaturated and saturated acids to eggs (Tocher 2003;Hauville et al 2015). Due to limited sample size, and because we did not examine the viability or survival of eggs or larvae, we are unable to infer the eventual reproductive success of these females.…”

“…Eggs are often enriched in 18:3n-3 and 18:1n-9 compared to muscle tissue, and the composition of visceral fat and liver fatty acids may vary dramatically (Beckmann et al 2014;Hauville et al 2015). Percids, like many determinate-spawning iteroparous species, draw on both visceral fat and muscle somatic lipid stores to allocate energy toward reproduction over a period of several months, and the relative contributions of these somatic lipids could influence egg composition .…”