Juvenile years of Atlantic salmon in the wild and in the hatchery: ecophysiological differences
Abstract This study investigated the ecophysiology of one of the world’s northernmost Atlantic salmon (Salmo salar L.) stocks in the River Teno. The juvenile years of salmon of same genetic background were studied in the wild and in the hatchery conditions. In addition, the maternal size effect on r...
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University of Oulu
2003
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ftunivoulu:oai:oulu.fi:isbn951-42-7220-X 2023-07-30T04:02:26+02:00 Juvenile years of Atlantic salmon in the wild and in the hatchery: ecophysiological differences Heinimaa, S. (Sirkka) 2003-12-12 application/pdf http://urn.fi/urn:isbn:951427220X eng eng University of Oulu info:eu-repo/semantics/altIdentifier/pissn/0355-3191 info:eu-repo/semantics/altIdentifier/eissn/1796-220X info:eu-repo/semantics/openAccess © University of Oulu, 2003 ecophysiology life-history maternal reproduction parr smolt Salmo salar info:eu-repo/semantics/doctoralThesis info:eu-repo/semantics/publishedVersion 2003 ftunivoulu 2023-07-08T20:01:18Z Abstract This study investigated the ecophysiology of one of the world’s northernmost Atlantic salmon (Salmo salar L.) stocks in the River Teno. The juvenile years of salmon of same genetic background were studied in the wild and in the hatchery conditions. In addition, the maternal size effect on reproduction was studied in wild females. Benefit of body size was not only quantitative but also qualitative in reproduction success of the wild female salmon in the River Teno. Total number of eggs and energy content of eggs were higher in big females than in smaller ones. In the hatchery, under natural day length and water temperature conditions, the growth rate, liver glycogen content and condition factor of the parr was higher than in the wild. The liver glycogen content of the hatchery-reared parr increased throughout the growing season and decreased during winter, whereas that of the wild parr was the lowest in summer, and stayed relative stable from September to May. The observed differences in annual fluctuation in liver glycogen content may reflect the differences in carbohydrate content of feed and in behaviour between the hatchery and wild. Overall, the hatchery-reared juveniles maturated and smoltificated 1–2 years earlier than the wild fish. The mean age of wild precocious males was 3 years and that of wild smolts 4 years. However, there was considerable variation in the age of precocious males (1–6 yr) and smolts (2–8 yr) in the wild. The maturing and smolting juvenile age groups were restricted to two (1–2 yr and 2–3 yr, respectively) in the hatchery. In June, the hypo-osmoregulatory ability of hatchery smolts was developed parallel to the wild smolts. Some differences in physiological parameters between different smolt groups could be observed in the wild and between hatchery-reared and wild smolts indicating that completing of smolting process varies to some extent under different conditions. However, the hatchery-reared smolts showed higher levels of fin damage and body energy stores than the wild ... Doctoral or Postdoctoral Thesis Atlantic salmon Salmo salar Jultika - University of Oulu repository Teno ENVELOPE(25.690,25.690,68.925,68.925) |
institution |
Open Polar |
collection |
Jultika - University of Oulu repository |
op_collection_id |
ftunivoulu |
language |
English |
topic |
ecophysiology life-history maternal reproduction parr smolt Salmo salar |
spellingShingle |
ecophysiology life-history maternal reproduction parr smolt Salmo salar Heinimaa, S. (Sirkka) Juvenile years of Atlantic salmon in the wild and in the hatchery: ecophysiological differences |
topic_facet |
ecophysiology life-history maternal reproduction parr smolt Salmo salar |
description |
Abstract This study investigated the ecophysiology of one of the world’s northernmost Atlantic salmon (Salmo salar L.) stocks in the River Teno. The juvenile years of salmon of same genetic background were studied in the wild and in the hatchery conditions. In addition, the maternal size effect on reproduction was studied in wild females. Benefit of body size was not only quantitative but also qualitative in reproduction success of the wild female salmon in the River Teno. Total number of eggs and energy content of eggs were higher in big females than in smaller ones. In the hatchery, under natural day length and water temperature conditions, the growth rate, liver glycogen content and condition factor of the parr was higher than in the wild. The liver glycogen content of the hatchery-reared parr increased throughout the growing season and decreased during winter, whereas that of the wild parr was the lowest in summer, and stayed relative stable from September to May. The observed differences in annual fluctuation in liver glycogen content may reflect the differences in carbohydrate content of feed and in behaviour between the hatchery and wild. Overall, the hatchery-reared juveniles maturated and smoltificated 1–2 years earlier than the wild fish. The mean age of wild precocious males was 3 years and that of wild smolts 4 years. However, there was considerable variation in the age of precocious males (1–6 yr) and smolts (2–8 yr) in the wild. The maturing and smolting juvenile age groups were restricted to two (1–2 yr and 2–3 yr, respectively) in the hatchery. In June, the hypo-osmoregulatory ability of hatchery smolts was developed parallel to the wild smolts. Some differences in physiological parameters between different smolt groups could be observed in the wild and between hatchery-reared and wild smolts indicating that completing of smolting process varies to some extent under different conditions. However, the hatchery-reared smolts showed higher levels of fin damage and body energy stores than the wild ... |
format |
Doctoral or Postdoctoral Thesis |
author |
Heinimaa, S. (Sirkka) |
author_facet |
Heinimaa, S. (Sirkka) |
author_sort |
Heinimaa, S. (Sirkka) |
title |
Juvenile years of Atlantic salmon in the wild and in the hatchery: ecophysiological differences |
title_short |
Juvenile years of Atlantic salmon in the wild and in the hatchery: ecophysiological differences |
title_full |
Juvenile years of Atlantic salmon in the wild and in the hatchery: ecophysiological differences |
title_fullStr |
Juvenile years of Atlantic salmon in the wild and in the hatchery: ecophysiological differences |
title_full_unstemmed |
Juvenile years of Atlantic salmon in the wild and in the hatchery: ecophysiological differences |
title_sort |
juvenile years of atlantic salmon in the wild and in the hatchery: ecophysiological differences |
publisher |
University of Oulu |
publishDate |
2003 |
url |
http://urn.fi/urn:isbn:951427220X |
long_lat |
ENVELOPE(25.690,25.690,68.925,68.925) |
geographic |
Teno |
geographic_facet |
Teno |
genre |
Atlantic salmon Salmo salar |
genre_facet |
Atlantic salmon Salmo salar |
op_relation |
info:eu-repo/semantics/altIdentifier/pissn/0355-3191 info:eu-repo/semantics/altIdentifier/eissn/1796-220X |
op_rights |
info:eu-repo/semantics/openAccess © University of Oulu, 2003 |
_version_ |
1772813225960669184 |