Protozan ectosymbionts on Atlantic salmon (Salmo salar L.) in a Hatchery in Hordaland, Western Norway: Morphology and Epizootiology
Protozoan ectosymbionts are commonly found on salmonids in Norwegian lakes and rivers. Salmon in hatcheries supplied with water from such watercourses are often infected with such organisms. Despite extensive salmon production, little is known about the infection dynamics of these symbionts on hatch...
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The University of Bergen
2003
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ftunivbergen:oai:bora.uib.no:1956/1622 2023-05-15T15:32:53+02:00 Protozan ectosymbionts on Atlantic salmon (Salmo salar L.) in a Hatchery in Hordaland, Western Norway: Morphology and Epizootiology Isaksen, Trond Einar 2003 22993534 bytes application/pdf http://hdl.handle.net/1956/1622 nob nob The University of Bergen urn:isbn:82-8088-303-7 (electronic version) http://hdl.handle.net/1956/1622 The author Copyright the author. All rights reserved VDP::Matematikk og Naturvitenskap: 400::Zoologiske og botaniske fag: 480::Marinbiologi: 497 Master thesis 2003 ftunivbergen 2023-03-14T17:41:56Z Protozoan ectosymbionts are commonly found on salmonids in Norwegian lakes and rivers. Salmon in hatcheries supplied with water from such watercourses are often infected with such organisms. Despite extensive salmon production, little is known about the infection dynamics of these symbionts on hatchery-reared salmon in Norway. The aim of this work was to study this in a fish farm located in Hordaland, western Norway. Eyed eggs, alevins, fry, parr and pre-smolt were collected approximately bi-weekly in the period January - November, year 2000 (n=2106). In addition, a total of 131 wild fish (salmon, brown trout, rainbow trout, charr and sticklebacks) were caught in the watercourse serving as a water supply to the hatchery, and examined for protozoan ectosymbionts. Five genera of protozoan symbionts were observed on the skin or gills of the farmed salmon. Ichthyobodo sp. (likely Ichthyobodo necator (Henneguy, 1883)) occurred on skin and gills of the farmed salmon. Infections occurred on fry in March (maximum prevalence of infection 38 %), parr in August (23 %) and parr/pre-smolt in September (54 %). Trichodina sp. (likely T. kamchatika Konovalov, Shevlyakov et Krasin, 1970) occurred at low density on the skin of the farmed salmon. It was detected in June (18 %) and again in September-November (4 %). The most commonly observed symbionts were the sessiline peritrich ciliates, Apiosoma piscicola (Blanchard, 1885) and Riboscyphidia sp. (Pickering, Strong et Pollard, 1985), which occurred on the skin (rarely gills), and the suctorian ciliate Capriniana piscium (Bütschli, 1889) that infected the gill lamella (rarely skin). Heavy infections with these ciliates occurred in July, with prevalence of infections equal or close to 100%. Apiosoma infections declined markedly in mid-August, coinciding with an increase in the intensity of Riboscyphidia infection that stayed high during autumn (September-November). Wild salmonids are probably the most important source of ciliate infections to the farmed salmon, while sticklebacks ... Master Thesis Atlantic salmon Salmo salar University of Bergen: Bergen Open Research Archive (BORA-UiB) Blanchard ENVELOPE(-62.083,-62.083,-64.733,-64.733) Krasin ENVELOPE(50.100,50.100,-68.367,-68.367) Norway Pollard ENVELOPE(64.617,64.617,-70.467,-70.467) |
institution |
Open Polar |
collection |
University of Bergen: Bergen Open Research Archive (BORA-UiB) |
op_collection_id |
ftunivbergen |
language |
Norwegian Bokmål |
topic |
VDP::Matematikk og Naturvitenskap: 400::Zoologiske og botaniske fag: 480::Marinbiologi: 497 |
spellingShingle |
VDP::Matematikk og Naturvitenskap: 400::Zoologiske og botaniske fag: 480::Marinbiologi: 497 Isaksen, Trond Einar Protozan ectosymbionts on Atlantic salmon (Salmo salar L.) in a Hatchery in Hordaland, Western Norway: Morphology and Epizootiology |
topic_facet |
VDP::Matematikk og Naturvitenskap: 400::Zoologiske og botaniske fag: 480::Marinbiologi: 497 |
description |
Protozoan ectosymbionts are commonly found on salmonids in Norwegian lakes and rivers. Salmon in hatcheries supplied with water from such watercourses are often infected with such organisms. Despite extensive salmon production, little is known about the infection dynamics of these symbionts on hatchery-reared salmon in Norway. The aim of this work was to study this in a fish farm located in Hordaland, western Norway. Eyed eggs, alevins, fry, parr and pre-smolt were collected approximately bi-weekly in the period January - November, year 2000 (n=2106). In addition, a total of 131 wild fish (salmon, brown trout, rainbow trout, charr and sticklebacks) were caught in the watercourse serving as a water supply to the hatchery, and examined for protozoan ectosymbionts. Five genera of protozoan symbionts were observed on the skin or gills of the farmed salmon. Ichthyobodo sp. (likely Ichthyobodo necator (Henneguy, 1883)) occurred on skin and gills of the farmed salmon. Infections occurred on fry in March (maximum prevalence of infection 38 %), parr in August (23 %) and parr/pre-smolt in September (54 %). Trichodina sp. (likely T. kamchatika Konovalov, Shevlyakov et Krasin, 1970) occurred at low density on the skin of the farmed salmon. It was detected in June (18 %) and again in September-November (4 %). The most commonly observed symbionts were the sessiline peritrich ciliates, Apiosoma piscicola (Blanchard, 1885) and Riboscyphidia sp. (Pickering, Strong et Pollard, 1985), which occurred on the skin (rarely gills), and the suctorian ciliate Capriniana piscium (Bütschli, 1889) that infected the gill lamella (rarely skin). Heavy infections with these ciliates occurred in July, with prevalence of infections equal or close to 100%. Apiosoma infections declined markedly in mid-August, coinciding with an increase in the intensity of Riboscyphidia infection that stayed high during autumn (September-November). Wild salmonids are probably the most important source of ciliate infections to the farmed salmon, while sticklebacks ... |
format |
Master Thesis |
author |
Isaksen, Trond Einar |
author_facet |
Isaksen, Trond Einar |
author_sort |
Isaksen, Trond Einar |
title |
Protozan ectosymbionts on Atlantic salmon (Salmo salar L.) in a Hatchery in Hordaland, Western Norway: Morphology and Epizootiology |
title_short |
Protozan ectosymbionts on Atlantic salmon (Salmo salar L.) in a Hatchery in Hordaland, Western Norway: Morphology and Epizootiology |
title_full |
Protozan ectosymbionts on Atlantic salmon (Salmo salar L.) in a Hatchery in Hordaland, Western Norway: Morphology and Epizootiology |
title_fullStr |
Protozan ectosymbionts on Atlantic salmon (Salmo salar L.) in a Hatchery in Hordaland, Western Norway: Morphology and Epizootiology |
title_full_unstemmed |
Protozan ectosymbionts on Atlantic salmon (Salmo salar L.) in a Hatchery in Hordaland, Western Norway: Morphology and Epizootiology |
title_sort |
protozan ectosymbionts on atlantic salmon (salmo salar l.) in a hatchery in hordaland, western norway: morphology and epizootiology |
publisher |
The University of Bergen |
publishDate |
2003 |
url |
http://hdl.handle.net/1956/1622 |
long_lat |
ENVELOPE(-62.083,-62.083,-64.733,-64.733) ENVELOPE(50.100,50.100,-68.367,-68.367) ENVELOPE(64.617,64.617,-70.467,-70.467) |
geographic |
Blanchard Krasin Norway Pollard |
geographic_facet |
Blanchard Krasin Norway Pollard |
genre |
Atlantic salmon Salmo salar |
genre_facet |
Atlantic salmon Salmo salar |
op_relation |
urn:isbn:82-8088-303-7 (electronic version) http://hdl.handle.net/1956/1622 |
op_rights |
The author Copyright the author. All rights reserved |
_version_ |
1766363364486807552 |