Vinsamlegast notið þetta auðkenni þegar þið vitnið til verksins eða tengið í það: http://hdl.handle.net/1946/29437
The European lobster is a commercially valuable crustacean found around most of coastal Europe. Annual catch is little over 5.000 tonnes and prices are high. At this time point the species is not farmed commercially but land based farming could provide stable supply of the product and maintain high quality.
To study the growth rate, metabolism and survival of the European lobster through respiration measurements, growth experiments and daily monitoring, juveniles were imported from the Institute of Marine Research in Norway and the National Lobster Hatchery in Cornwall, UK, to Iceland. They were reared in the University of Iceland’s Research Centre in Sudurnes in Sandgerdi and in Sæbýli ehf in Eyrarbakki.
Growth experiments showed reduced growth in colder water as well as a lower feed conversion efficiency (FCE), while the survival rate was higher in colder water. Growth was similar between lobsters held in flow through system and in semi–RAS system and between lobsters fed with commercial Arctic char feed and specially formulated lobster feed. Lobsters receiving shrimp supplements along with Arctic char feed grew significantly more than the ones fed with dry feed only. When two photoperiods were compared, the growth, oxygen consumption rate (OCR) and FCE were not different between treatment groups.
Respiration measurements showed that metabolism decreases per kilogram as individual lobsters gain size, ranging from 0.0035 mgO2/g/L/min for the smallest individuals weighing less than 1 g down to less than 0.0005 mgO2/g/L/min for the largest lobster weighing 35 g. The metabolism increases with rising temperatures for all lobster sizes combined, from 0.0016 mgO2/g/L/min at 10°C to 0.0026 mgO2/g/L/min at 20°C. The metabolism also rises after feeding, by 0.0015 mgO2/g/L/min at 10°C and by 0.0020 mgO2/g/L/min at 20°C. The rise in respiration following feeding, or specific dynamic action (SDA), was higher at 20°C. The increase in OCR at 10°C was on average 0.0015 mgO2/g/L/min but was 0.0020 mgO2/g/L/min at 20°C. The lobsters are well equipped to withstand temperature fluctuations as little difference was detected in metabolism between individuals recently transferred between temperatures and those who had acclimated.