Developmental regulation of Uroteuthis edulis through the tissue-specific energy allocation from feeding behaviors in the East China sea

Uroteuthis edulis (U. edulis) is one of the dominant cephalopod species in the East China Sea and has significant economic value. U. edulis is characterized by a short life cycle and rapid growth and its energy allocation strategy suggests its adaptive mechanisms for growth and reproduction. In this study, the differences in fatty acid composition and stable isotopes among different tissues were analyzed to reveal their energy allocation patterns for growth and reproduction. The differences in fatty acid composition, δ¹³C and δ¹⁵N values among different tissues (muscle vs ovary; muscle vs oviduct) were significant (P < 0.05). The significantly different fatty acids included docosahexaenoic acid (C22:6n3, DHA), palmitic acid (C16:0), arachidonic acid (C20:4n6, ARA), eicosapentaenoic acid (C20:5n3, EPA), stearic acid (C18:0), and myristate acid (C14:0). PUFA content in the ovary was higher than that in muscle and oviduct. δ¹³C and δ¹⁵N values among different tissues (muscle vs ovary; muscle vs oviduct) were significantly different and the ratio of stable isotopes in muscle was higher than that in ovary and oviduct. C22:6n3 was significantly positively correlated with reproductive investment index (RI) (P < 0.05) and δ¹⁵N was significantly positively correlated with body condition index (CI) (P < 0.05). The study revealed the regulatory roles of the differential energy allocation pattern among various tissues and feeding behaviors in individual development of U. edulis in the East China Sea and offered a scientific basis for studying its life-history.