caa a22 4500 605464596 CHVBK 20210128100258.0 cr unu---uuuuu 210128e20150801xx s 000 0 eng 10.1007/s10499-014-9859-2 doi (NATIONALLICENCE)springer-10.1007/s10499-014-9859-2 Growth performance of Noble Crayfish Astacus astacus in recirculating aquaculture systems [Elektronische Daten] [Uli Seemann, Kai Lorkowski, Matthew Slater, Friedrich Buchholz, Bela Buck] There is growing interest in using recirculating aquaculture systems (RAS) to raise noble crayfish Astacus astacus a valuable and once plentiful food species in Europe, now a highly endangered species. The growth and survival of A. astacus was compared in growth trials in RAS and open-pond systems (OPS) over a period of 2months. Energy and lipid content of available diets and crayfish tissue were also determined. Growth of A. astacus during summer was significantly (p<0.01, one sample t test) higher in OPS (SGR 1.23) than in RAS even at the highest feeding ration provided at 5% bw/d−1 (RAS HI SGR 0.78±0.06). OPS crayfish also had significantly (p<0.01 OPS vs. all RAS treatments; Pairwise Wilcoxon) higher lipid content (8.51%) than RAS crayfish (RAS HI 5.73%, RAS MED 6.93%, RAS LOW 5.92%). Survival rates in RAS were, however, 100% compared with previous observations in OPS of approx. 70%. While results showed OPS growth exceeds than that in RAS in the short term, RAS survival rates and annualized growth performance may outweigh this disadvantage, particularly if optimal artificial diets for RAS holding are provided. Feed and crayfish analysis indicated that culturing A. astacus in RAS require a diet protein content exceeding 30% and lipid content of <13%, indicating that the carp diet supplied was not optimal. RAS culture allows this valuable species to be cultured in controlled, disease-free enclosed systems—resulting in high-value food products as well as high-quality seedlings for restocking purpose. Springer International Publishing Switzerland, 2014 Astacus astacus nationallicence Crayfish feed nationallicence Feed ratio nationallicence Lipid content nationallicence Pond system nationallicence AFK : Surface of filter body [m2/m3] 600m2/m3 (Spieck et al. 2007) nationallicence AN : Amount of affiliated nitrogen (80% nationallicence van Wyk 1999) nationallicence ENH3 : Ammonia nitrogen amount of excretion (75%, van Wyk 1999) nationallicence FImax : Max. feed intake per day [g] nationallicence NC : Amount of nitrogen in the protein (16% nationallicence NR : Nitrification rate of filter body [gN/m2d] nationallicence OPS : Open-pond systems nationallicence PC : Amount of protein in the feed (25%, CYPRININ K2) nationallicence RAS : Recirculating aquaculture systems nationallicence RAS HI : Treatment of 5% nationallicence RAS LOW : Treatment of 3% nationallicence RAS MED : Treatment of 4% nationallicence TAN : Total amount of imported nitrogen [gN/d] nationallicence VBF : Volume of biofilter [m3] nationallicence Seemann Uli Institute for Marine Resources GmbH, Bussestr. 27, 27570, Bremerhaven, Germany aut Lorkowski Kai University of Applied Sciences Bremerhaven, 27568, Bremerhaven, Germany aut Slater Matthew Institute for Marine Resources GmbH, Bussestr. 27, 27570, Bremerhaven, Germany aut Buchholz Friedrich Alfred Wegener Institute Helmholtz Center for Polar and Marine Research, 27570, Bremerhaven, Germany aut Buck Bela University of Applied Sciences Bremerhaven, 27568, Bremerhaven, Germany aut Aquaculture International Springer International Publishing 23/4(2015-08-01), 997-1012 0967-6120 23:4<997 2015 23 10499 https://doi.org/10.1007/s10499-014-9859-2 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10499-014-9859-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Seemann Uli Institute for Marine Resources GmbH, Bussestr. 27, 27570, Bremerhaven, Germany aut NATIONALLICENCE 700 1- Lorkowski Kai University of Applied Sciences Bremerhaven, 27568, Bremerhaven, Germany aut NATIONALLICENCE 700 1- Slater Matthew Institute for Marine Resources GmbH, Bussestr. 27, 27570, Bremerhaven, Germany aut NATIONALLICENCE 700 1- Buchholz Friedrich Alfred Wegener Institute Helmholtz Center for Polar and Marine Research, 27570, Bremerhaven, Germany aut NATIONALLICENCE 700 1- Buck Bela University of Applied Sciences Bremerhaven, 27568, Bremerhaven, Germany aut NATIONALLICENCE 773 0- Aquaculture International Springer International Publishing 23/4(2015-08-01), 997-1012 0967-6120 23:4<997 2015 23 10499