Paranucleospora theridion (Microsporidia) infection dynamics in farmed Atlantic salmon Salmo salar put to sea in spring and autumn

The microsporidian Paranucleospora theridion (syn. Desmozoon lepeophtheirii) is a parasite of Atlantic salmon Salmo salar and also a hyperparasite of the salmon louse Lepeophtheirus salmonis. The parasite develops 2 types of spores in salmon, cytoplasmic spores in phagocytes and intranuclear spores...

Full description

Saved in:
Bibliographic Details
Published in:Diseases of aquatic organisms 2012-10, Vol.101 (1), p.43-49
Main Authors: Sveen, S, Øverland, H, Karlsbakk, E, Nylund, A
Format: Article
Language:English
Subjects:
Animals
Aquaculture
Base Sequence
DNA, Fungal - chemistry
DNA, Fungal - genetics
Fish Diseases - immunology
Fish Diseases - microbiology
Kidney Diseases - immunology
Kidney Diseases - microbiology
Kidney Diseases - veterinary
Microsporidia - genetics
Microsporidia - immunology
Microsporidiosis - immunology
Microsporidiosis - parasitology
Microsporidiosis - veterinary
Molecular Sequence Data
Phthiraptera - immunology
Phthiraptera - microbiology
Real-Time Polymerase Chain Reaction
RNA, Fungal - chemistry
RNA, Fungal - genetics
Salmo salar
Seasons
Sequence Alignment
Sequence Analysis, DNA
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The microsporidian Paranucleospora theridion (syn. Desmozoon lepeophtheirii) is a parasite of Atlantic salmon Salmo salar and also a hyperparasite of the salmon louse Lepeophtheirus salmonis. The parasite develops 2 types of spores in salmon, cytoplasmic spores in phagocytes and intranuclear spores in epidermal cells. The former type of development is assumed to be propagative (autoinfection), while the epidermal spores transfer the parasite to lice. Development in lice is extensive, with the formation of xenoma-like hypertrophic cells filled with microsporidian spores. We show that salmon are infected in the absence of lice, likely through waterborne spores that initiate infections in the gills. During summer and autumn the parasite propagates in the kidney, as evidenced by peaking normalised expression of P. theridion rRNA. Lice become infected during autumn, and develop extensive infections during winter. Lice mortality in winter and spring is likely responsible for a reservoir of spores in the water. Salmon transferred to sea in November (low temperature) did not show involvement of the kidney in parasite propagation and lice on such fish did not become infected. Apparently, low temperatures inhibit normal P. theridion development in salmon.
ISSN:0177-5103
1616-1580
DOI:10.3354/dao02464