Fatty Acid Profile of Neutral and Polar Lipid Fraction of Wild Eggs and Hatchlings from Wild and Captive Reared Broodstock of Octopus vulgaris

Abstract

The culture of Octopus vulgaris is constrained by unsolved problems in paralarvae rearing, mainly associated to the unknown nutritional requirements of this species in early stages. In this article we studied the fatty acid profile (total, neutral, and polar lipid fractions) in wild eggs and wild hatchlings, collected in Gran Canaria (SW) (Spain) with artificial dens, in comparison to hatchlings obtained in captivity from broodstock fed on trash fish species. Total lipids were 11.5–13.5% dw, with the polar fraction representing a 70.6–75.5% of total lipid, with lower values in wild hatchling in comparison with captive ones. Docosahexaenoic acid (DHA) was the main component in neutral and polar fatty acid profile in all samples, underlying its importance in this species. Decreasing levels of saturates and arachidonic acid (ARA) from wild eggs to hatchlings, mainly associated to the polar fraction, suggest their use during embryonic development. In hatchlings, increasing levels of oleic acid in the neutral fraction and eicosapentaenoic acid (EPA) in the polar fraction, suggests their importance in hatchlings quality. Wild hatchlings showed in the polar fraction higher oleic acid and ARA, and lower DHA/ARA and EPA/ARA ratios in comparison with captive hatchlings, suggesting a difference in paralarvae nutritional status. These results suggest the importance of n-3 highly unsaturated fatty acids (HUFA), oleic acid, and ARA, presented in the adequate lipid fraction, in the diet of broodstock and paralarvae of O. vulgaris.

Biochemical Composition and Energy Strategy Along the Reproductive Cycle of Female Octopus vulgaris in Galician Waters (NW Spain)

“…The PCA carried out on the FA profile of the wild developmental stages of O. vulgaris revealed a clear separation of the paralarvae from the other stages due to a higher contribution of DHA/ARA and EPA/ARA ratios. Previous research showed a reduction in some SAFA (14:0 and 16:0) and ARA content from wild eggs to wild hatchlings, suggesting their use during the embryonic phase (Estefanell et al, 2017). In this regard, we observed a lower content in ARA in the paralarvae, which would explain the higher DHA/ARA and EPA/ARA ratios, together with a reduction in 14:0 content.…”

“…In this regard, we observed a lower content in ARA in the paralarvae, which would explain the higher DHA/ARA and EPA/ARA ratios, together with a reduction in 14:0 content. Moreover, Estefanell et al (2017) reported also higher contents of 18:1n9 and EPA in wild hatchlings compared to wild eggs suggesting their importance as phospholipids or energy substrate at this stage. We also detected an increment of 18:1n9 in the paralarvae, along with a higher content of some SAFA (e.g., 16:0) and other C18 unsaturated FA (e.g., 18:2n6c), which could be due to exogenous feeding as suggested by Lourenço et al (2017).…”

Sexual maturation and embryonic development in octopus: use of energy and antioxidant defence mechanisms usingOctopus mimusas a model

“…Lipids (measured as triacyl glycerides: TG) and free cholesterol are absorbed in DG and transported by lipoproteins (LP) to ovarium, between other tissues (Heras & Pollero, 1990; Heras & Pollero, 1992). TG are accumulated during physiological maturation and early functional maturation and presumably converted at least in part, as cholesterol at the end of the maturation process (Estefanell et al ., 2017).…”

“…Fatty acids accumulated as TG were likely transformed and stored into the eggs as yolk. Moderated cholesterol levels detected at the end of the maturation process suggest that cholesterol was also stored in the yolk to be used by the embryos throughout their development (Estefanell et al 2017).…”

Peer Review #2 of "Maturation trade-offs in octopus females and their progeny: energy, digestion and defence indicators (v0.2)"

“…The latter is evidenced by low TG levels at the end of the maturation process (late functional maturation) in the ovaries of the females, suggesting their transformation and storage into the eggs as yolk. As Chol accumulated with maturity progression from physiological maturation to late functional maturation, Chol may also be stored in the yolk to be used by the embryos throughout their development (Estefanell et al 2017).…”