Abstract
Optimal rearing temperatures for European lobster Homarus gammarus in aquaculture differ from those prevalent in their aquatic ecosystems and acclimating juveniles to the prevailing temperatures before release may aid in the success of re-stocking programs. As the dietary nutritional composition is important for optimal performance of H. gammarus, in this study we aimed to investigate whether juvenile growth and energy metabolism responses to temperature variation could be modulated by the diet. Prior to the trial start, the juveniles were divided into two groups. One was maintained at 19 °C and the other gradually adapted to 13 °C. From this point and for a 24-day period, juveniles (~ 100 mg) within each temperature group were assigned one of two experimental diets: a carbohydrate-rich (HC) or a protein-rich (HP) extruded feed. Antarctic krill (AK) was used as a control diet within each temperature group. Feed intake, growth, glycogen, glucose, lactate, and protein concentrations of H. gammarus in each group were evaluated. Regardless the dietary treatment, feed intake, cephalothorax protein and glucose, and abdominal glycogen and glucose levels decreased at colder temperature. The effect of lower temperature on growth (SGR and moulting rate declines) and energy metabolism (reduction on cephalothorax glycogen and protein) was more severe in HC-fed lobsters. Results showed that the impact of lower temperature on juvenile H. gammarus can be modulated by diet highlighting the importance of designing optimized diets not only for growth and feed efficiency but also for resilience to environmental variation.
Highlights
The European lobster Homarus gammarus is a commercially impor tant crustacean widely distributed from northern Norway to Azores and Morocco (Triantafyllidis et al, 2005)
As the dietary nutritional composition is important for optimal performance of H. gammarus, in this study we aimed to investigate whether juvenile growth and energy metabolism responses to temperature variation could be modulated by the diet
This study showed that the resiliency of juvenile H. gammarus to the effects of temperature variation on growth and energy metabolism can be modulated by the dietary composition
Summary
The European lobster Homarus gammarus is a commercially impor tant crustacean widely distributed from northern Norway to Azores and Morocco (Triantafyllidis et al, 2005). Despite the relative success of some programs in recovering European lobster natural stocks (Agnalt, 2004), the hatcheryrearing of larvae and juvenile lobsters is not yet a sustainable practice (Beal et al, 2002). The lack of suitable artificial diets capable of reducing feeding costs and simplifying production practices remains as a major issue, together with high mortalities associated to cannibalistic behavior (Hinchcliffe et al, 2020; Powell, 2016; Powell et al, 2017). The substitution of natural diets for artificial feeds has been inves tigated in both the American lobster, Homarus americanus and the
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
