Fróðskaparrit - 01.01.2002, Side 121

MYXIDIUM GADI (GEORGEVITCH, 1916) og MYXIDIUM OVIFORME (PARISI, 1912)
í GALLBLØÐRUNI Á TOSKl (GADUS MORHUA L.)
119
Bank. In the North Sea there is also an ab-
sence of Myxidium gadi in cod. In Norwe-
gian waters Myxidium gadi also seems to
be absent.
Myxidium oviforme shows an opposite
pattern in distribution throughout the North
Atlantic ocean. Although examining 925
specimens of cod no infection was found
by Khan et al. (1986). My own investiga-
tions show a prevalence between 10-34%,
which is approximately the same preva-
lence that Mackenzie and Kalavati (1995)
find in the North Sea. In the Barents Sea the
prevalence is 8-27%, and in two Norwegian
fjords the prevalence is 47-73% (Larsen et
al., 1997). In the West Murman part of the
Barents Sea Karasev et al. (1996) find the
prevalence to be 3-9%. It is scientifecly im-
possible to conclude anything on the preva-
lences in the entire North Atlantic ocean,
because sampling procedures and laborato-
ry procedures are not comparable in all the
mentioned studies. Nevertheless a large
scale study might prove very interesting es-
pecially from a phylogenetic point of view.
Acknowledgements
To K. MacKenzie, Marine biological laboratory Aber-
deen for help with species identification, M. Køie for
scientific supervision through the entire research pro-
ject. To P. H. Enckell and D. P. Højgaard for critically
reading the manuscript before publication. To the staff
at the Faroese fisheries laboratory and the crew on
Magnus Heinason.
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