Physiological response of adult Antarctic krill, Euphausia superba , to long-term starvation

摘要: Adult Euphausia superba survive winter without or with little feeding. It is not exactly known whether the scarcity of food an internal clock, set by natural Antarctic light regime, are responsible for non-feeding. Our research questions were therefore following: (1) How will physiological and biochemical conditions krill change during long-term starvation at constant regime? (2) If how do enzyme activities such starvation? (3) What influence availability versus that To answer these questions, adult starved under laboratory 12 weeks regime (12:12; dark/light) impact on functions was studied. Initial experimental condition resembled late spring in field fully active metabolism low lipid reserves. Metabolic activity enzymes catabolising lipids decreased after onset remained throughout, whereas reserves declined composition changed. Mass size while inter-moult period increased. Depletion storage- structural metabolites occurred order depot glycogen until proteins almost exclusively used 6–7 weeks starvation. Results confirmed various proposed overwintering mechanisms as metabolic slowdown, slow growth shrinkage use However, changes motion shortage only, i.e. trigger a changing regime.