Náttúrufræðingurinn - 2008, Blaðsíða 58

Náttúrufræðingurinn
The aim is to develop a farming con-
cept for a full-scale production in close
co-operation with a commercial wolffish
farmer (Hlýri ehf, Neskaupstaður, East
Iceland). Two different source popula-
tions were investigated by rearing fish
from Iceland and Norway and investi-
gating differences in primary aquacul-
ture characteristics (growth, food con-
version efficiency, protein synthesis and
survival) followed by a more detailed
study of production characteristics in the
Iceland population. The Icelandic group
was found to have more favourable pro-
duction characteristics compared to fish
from Norway. The Icelandic group has
optimal temperature for growth and
food conversion between 6-8°C which
makes this an excellent species for cul-
ture in Iceland. An important relation-
ship between enzyme activity, mRNA
myosin expression and growth in the
Icelandic fish has been found that will
help to identify best offspring groups for
aquaculture purposes. Spotted wolffish
can be reared at high densities and in
shallow raceways. Rearing in shallow
raceways is preferable as growth and
feed conversion efficiency in spotted
wolffish culture can be improved in such
systems.
The population genetics of this spe-
cies was totally unknown so it was
found useful to investigate the character-
istics of two different source populations.
Several methods were tested, including
haemoglobin, allozymes, RFLP and DNA
microsatellites. The most promising
markers were found to be allozymes and
RFLP mtDNA markers. The results show
high level of geographic population
structure between the westem Atlantic,
middle and eastern Atlantic and Baltic
Sea, and thus the findings may be useful
in devising overall management and
conservation strategies for the species.
Cryopreservation of sperm is a proc-
ess where sperm is mixed with extender
and cryoprotectant designed to dehy-
drate the cells up to the point so that ice
crystals do not form with subsequent
cell mpture as the cells freeze. The spe-
cial characteristics of the spotted wolff-
ish sperm add to the necessity of species
specific adaptations of freezing methods.
Preliminary trials show that it is feasible
to use cryopreservation of sperm to
ensure a year-round availability of milt.
ÞAKKJR
Rannsóknir á eldiseiginleikum hlýra hafa verið styrktar af Rannís, AVS
rannsóknasjóðnum og af NORA (Norræna Atlantssamstarfinu) og er
þessum aðilum þakkaður veittur stuðningur. Sindri Sigurðsson hefur verið
vakinn og sofinn yfir velferð hlýrans í mörg ár og eru honum færðar bestu
þakkir fyrir eldmóð og áhuga.
HEIMILDIR
1. Gunnar Jónsson 1992. íslenskir fiskar. Fjölvaútgáfan, Reykjavík. 568 bls.
2. Foss, A., Albert K. Imsland, Falk-Petersen, I.B. & Oiestad, V. 2004. A
review of the culture potential of spotted wolffish Anarhichas minor
Olafsen. Reviews in Fish Biology and Fisheries 14. 277-294.
3. Ostvedt, O.J. 1963. On the life history of the spotted catfish (Anarhichas
minor Olafsen). Fiskeridirektoratets Skrifter Serie Havundersokelser 13.
54-72.
4. Karl Gunnarsson, Gunnar Jónsson & Ólafur Karvel Pálsson 1998.
Sjávamytjar við ísland. Mál og menning. 282 bls.
5. Falk-Petersen, I.B., Hansen, T.K., Fieler, R. & Sunde, L.M. 1999. Cultivation
of the spotted wolffish Anarhichas minor (Olafsen) - a new candidate for
cold-water fish farming. Aquaculture Research 30. 711-718.
6. Barsukov, V.V. 1986. Anarhichadidae. í: Fishes of the North-eastem
Atlantic and the Mediterranean, Vol. 3. (ritstj. Whitehead, P.J.P., Bauchot,
M. -L., Hureau, J.-C., Nielsen, J. & Tortonese, E.). UNESCO, Paris. Bls.
1113-1116.
7. Templeman, W. 1986. Contribution to the Biology of the Spotted Wolffish
(Anarhichas minor) in the Northwest Atlantic. Joumal of Northwest
Atlantic Fisheries Science 7. 47-55.
8. Shevelev, M.S. 1988. Ontogenetic stages in spotted wolffish (Anarhichas
minor Olafsen) from the Barents Sea. ICES CM/ G31.12 bls.
9. Kime, D.E. & Tveiten, H. 2002. Unusual motility characteristics of sperm
of spotted wolffish. Joumal of Fish Biology 61. 1549-1559.
10. Hansen, T.K. & Falk-Petersen, I.B. 2001. The influence of rearing
temperature on early development and growth of spotted wolffish
Anarhichas minor (Olafsen). Aquaculture Research 32. 369-378.
11. Barsukov, V.V. 1959. The Wolffish (Anarhichadidae). Fauna SSR Moscow
N. S. 73 (þýtt af Smithsonian Institute 1972). NTIS, Springfield, VA, USA.
12. Shevelev, M.S. 1994. Migration pattem of spotted catfish (Anarhichas
minor Olafsen) in the Barents Sea and adjacent waters. ICES CM/0:9.
13. Albert K. Imsland, Foss, A., Sparboe, L.O. & Sindri Sigurðsson 2006. The
effect of temperature and fish size on growth and feed efficiency ratio of
juvenile spotted wolffish Anarhichas minor. Joumal of Fish Biology 68.
1107-1122.
14. Moksness, E. 1994. Growth rates of the common wolffish, Anarhichas
lupus L., and spotted wolffish, A. minor Olafsen, in captivity. Aquaculture
and Fisheries Management 25. 363-371.
15. Steinsland, K. 2006. Population genetic study of spotted wolffish
(Anarhichas minor) in the North-Atlantic waters. M.Sc. thesis,
Department of Biology, University of Bergen, Norway.
16. Albert K. Imsland, Le Frangois, N.R., Lamarre, S.G., Ditlecadet, D., Sindri
Sigurðsson & Foss, A. 2006. Myosin expression levels and enzyme
activity in juvenile spotted wolffish muscle: a method for monitoring
growth rates. Canadian Joumal of Fisheries and Aquatic Sciences 63.
1959-1967.
17. Albert K. Imsland, Snorri Gunnarsson, Foss, A., Sparboe, L.O., Oiestad, V.
& Sindri Sigurðsson 2007. Comparison of juvenile spotted wolffish,
Anarhichas minor, growth in shallow raceways and circular tanks.
Joumal of the World Aquaculture Society 38.154-160.
18. Mortensen, A., Toften, H. & Aas, K. 2007. Cage culture of spotted
wolffish (Anarhichas minor Olafsen). Aquaculture 264. 475-^478.
UM HÖFUNDANA
Albert Kjartansson Imsland (f. 1965) lauk cand.mag.-
prófi í líffræði frá Háskólanum í Bergen árið 1991, meist-
araprófi í eldi sjávarfiska árið 1993 og doktorsprófi í
sömu grein árið 1997 frá sama háskóla. Þaðan lauk hann
síðan einnig meistaraprófi í líftölfræði árið 2001. Albert
hefur stundað eldisrannsóknir á kaldsjávartegundum
og skoðað sérstaklega áhrif umhverfis og erfða á vöxt og
kynþroska hjá hlýra, lúðu, sandhverfu, sólflúm og
þorski. Hann starfar sem rannsóknastjóri fiskeldis hjá
Akvaplan-niva og sem prófessor í fiskeldi við Háskólann
í Bergen.
Snorri Gunnarsson (f. 1968) lauk BS-prófi í líffræði frá
Háskóla íslands árið 1993 og kandídatsprófi í eldi sjáv-
arfiska 2001 frá Háskólanum í Bergen. Hann hefur
unnið við eldisrannsóknir frá 1995, fyrst hjá Stofnfiski
hf. og frá 2004 hjá Akvaplan-niva á íslandi.
PÓST- OG NETFÖNG HÖFUNDA/AUTHORS’ADDRESSES
Albert Imsland
albert.imsland@akvaplan.niva.no
Snorri Gunnarsson
snorri.gunnarsson@akvaplan.niva.no
Akvaplan-niva á íslandi
Akralind 4
IS-201 Kópavogur
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