stage with subsequent migration from the gill epithelium
into the gill blood vessels where replication and release of
the parasite occurs. C. shasta spores are elongate and contain
two polar capsules at the anterior margin (Fig. 9.1).
Diagnosis is carried out by the microscopic observation
of typical spores in scrapes or stained sections prepared from
the lower intestine, gall bladder or lesion within the body
musculature. A polymerase chain reaction (PCR) is also
available for diagnosis.
9.1.2 Chloromyxum spp.
Several myxosporeans are reported to infect salmonids, and
C. truttae affecting farmed brown trout may result in a loss
of appetite, emaciation and yellow discolouration of the skin
and fins. Internally, the liver may be yellowish with hypertrophy of the gall bladder and associated enteritis. Infection
can persist for several months and is fatal to some fish
groups.
Table 9.1 Principal Metazoa parasites from salmonids
Name
Phyla or class
Common location
Environment
Ceratomyxa shasta
Myxozoa
Intestine
FW
Chloromyxum truttae
Myxozoa
Gall bladder
FW
Kudoa thyrsites
Myxozoa
Musculature
SW
Henneguya zschokkei
Myxozoa
Musculature
FW
Myxidium truttae
Myxozoa
Liver
FW, SW
Myxobolus cerebralis
Myxozoa
Cartilage, brain
FW
Parvicapsula pseudobranchicola
Myxozoa
Kidney, pseudobranch
SW
Sphaerospora truttae
Myxozoa
Kidney
FW
Tetracapsuloides bryosalmonae
Myxozoa
Many organs
FW
Philonema oncorhynchi
Nematoda
Abdominal cavity
FW
Cystidicola farionis
Nematoda
Swim bladder
FW, SW
Pseudoterranova decipiens
Nematoda
Musculature, liver
SW
Eustrongyloides sp.
Nematoda
Abdominal cavity
FW
Anisakis simplex
Nematoda
Musculature, abdominal cavity, vent
SW
a
Eubothrium spp.
Cestoda
Intestine
FW, SW
Diphyllobothrium ditremum, D. dendriticum
Cestoda
On intestine, liver, abdominal cavity
FW
a
Sanguinicola spp.
Trematoda
Heart, gills
FW
Cryptocotyle lingua
Trematoda
Gills, external surface
SW
Diplostomum spathaceum
Trematoda
Eye, brain
FW
Phyllodistomum umblae
Trematoda
Kidney, urinary bladder
FW
Apatemon gracilis
Trematoda
Pericardial and abdominal cavity
FW
a
Cotylurus / Ichthyocotylurus spp.
Trematoda
Heart
FW
Stephanostomum tenue
Trematoda
Heart
SW
Nanophyetus salmincola
Trematoda
Many organs
FW
Gyrodactylus salaris
Monogenea
External surface
FW
Gyrodactyloides bychowskii
Monogenea
Gills
SW
Discocotyle sagittata
Monogenea
Gills
FW, BW
Acanthocephalus spp.
Acanthocephala
Intestine
FW, SW
Echinorhynchus spp.
Acanthocephala
Intestine
Normally SW
a
Pomphorhynchus laevis
Acanthocephala
Intestine
FW
Lepeophtheirus salmonis
Maxillopoda
External surface
SW
Caligus elongatus
Maxillopoda
External surface
SW
Caligus rogercresseyi
Maxillopoda
External surface
SW
Argulus spp.
Maxillopoda
Skin, external surface
FW
Salmincola spp.
Maxillopoda
Gills, opercula
FW, SW
Margaritifera margaritifera
Bivalvia
Gills
FW
Piscicola geometra
Annelida
Gills, external surface
FW
a
FW freshwater, SW sea water, BW brackish water
a
Also found in anadromous fish
124
9 Metazoa
into the gill blood vessels where replication and release of
the parasite occurs. C. shasta spores are elongate and contain
two polar capsules at the anterior margin (Fig. 9.1).
Diagnosis is carried out by the microscopic observation
of typical spores in scrapes or stained sections prepared from
the lower intestine, gall bladder or lesion within the body
musculature. A polymerase chain reaction (PCR) is also
available for diagnosis.
9.1.2 Chloromyxum spp.
Several myxosporeans are reported to infect salmonids, and
C. truttae affecting farmed brown trout may result in a loss
of appetite, emaciation and yellow discolouration of the skin
and fins. Internally, the liver may be yellowish with hypertrophy of the gall bladder and associated enteritis. Infection
can persist for several months and is fatal to some fish
groups.
Table 9.1 Principal Metazoa parasites from salmonids
Name
Phyla or class
Common location
Environment
Ceratomyxa shasta
Myxozoa
Intestine
FW
Chloromyxum truttae
Myxozoa
Gall bladder
FW
Kudoa thyrsites
Myxozoa
Musculature
SW
Henneguya zschokkei
Myxozoa
Musculature
FW
Myxidium truttae
Myxozoa
Liver
FW, SW
Myxobolus cerebralis
Myxozoa
Cartilage, brain
FW
Parvicapsula pseudobranchicola
Myxozoa
Kidney, pseudobranch
SW
Sphaerospora truttae
Myxozoa
Kidney
FW
Tetracapsuloides bryosalmonae
Myxozoa
Many organs
FW
Philonema oncorhynchi
Nematoda
Abdominal cavity
FW
Cystidicola farionis
Nematoda
Swim bladder
FW, SW
Pseudoterranova decipiens
Nematoda
Musculature, liver
SW
Eustrongyloides sp.
Nematoda
Abdominal cavity
FW
Anisakis simplex
Nematoda
Musculature, abdominal cavity, vent
SW
a
Eubothrium spp.
Cestoda
Intestine
FW, SW
Diphyllobothrium ditremum, D. dendriticum
Cestoda
On intestine, liver, abdominal cavity
FW
a
Sanguinicola spp.
Trematoda
Heart, gills
FW
Cryptocotyle lingua
Trematoda
Gills, external surface
SW
Diplostomum spathaceum
Trematoda
Eye, brain
FW
Phyllodistomum umblae
Trematoda
Kidney, urinary bladder
FW
Apatemon gracilis
Trematoda
Pericardial and abdominal cavity
FW
a
Cotylurus / Ichthyocotylurus spp.
Trematoda
Heart
FW
Stephanostomum tenue
Trematoda
Heart
SW
Nanophyetus salmincola
Trematoda
Many organs
FW
Gyrodactylus salaris
Monogenea
External surface
FW
Gyrodactyloides bychowskii
Monogenea
Gills
SW
Discocotyle sagittata
Monogenea
Gills
FW, BW
Acanthocephalus spp.
Acanthocephala
Intestine
FW, SW
Echinorhynchus spp.
Acanthocephala
Intestine
Normally SW
a
Pomphorhynchus laevis
Acanthocephala
Intestine
FW
Lepeophtheirus salmonis
Maxillopoda
External surface
SW
Caligus elongatus
Maxillopoda
External surface
SW
Caligus rogercresseyi
Maxillopoda
External surface
SW
Argulus spp.
Maxillopoda
Skin, external surface
FW
Salmincola spp.
Maxillopoda
Gills, opercula
FW, SW
Margaritifera margaritifera
Bivalvia
Gills
FW
Piscicola geometra
Annelida
Gills, external surface
FW
a
FW freshwater, SW sea water, BW brackish water
a
Also found in anadromous fish
124
9 Metazoa