Plasma thyroid hormones during smoltification of yearling and underyearling coho salmon and yearling chinook salmon and steelhead trout

Aquaculture ◽  
1982 ◽  
Vol 28 (1-2) ◽  
pp. 39-48 ◽  
Author(s):  
Walton W. Dickhoff ◽  
Leroy C. Folmar ◽  
James L. Mighell ◽  
Conrad V.W. Mahnken
Keyword(s):  
Thyroid Hormones ◽  
Chinook Salmon ◽  
Coho Salmon ◽  
Steelhead Trout

Relation of Water Temperature to Flexibacter columnaris Infection in Steelhead Trout (Salmo gairdneri), Coho (Oncorhynchus kisutch) and Chinook (O. tshawytscha) Salmon

1975 ◽  
Vol 32 (9) ◽  
pp. 1553-1559 ◽  
Author(s):  
R. A. Holt ◽  
J. E. Sanders ◽  
J. L. Zinn ◽  
J. L. Fryer ◽  
K. S. Pilcher
Keyword(s):  
Water Temperature ◽  
Experimental Infection ◽  
Chinook Salmon ◽  
Coho Salmon ◽  
Oncorhynchus Kisutch ◽  
Disease Process ◽  
Salmo Gairdneri ◽  
Contact Method ◽  
Steelhead Trout ◽  
Time To Death

The effect of water temperature upon mortality from experimental infection by Flexibacter columnaris and on mean time to death was investigated in juvenile steelhead trout (Salmo gairdneri), coho salmon (Oncorhynchus kisutch), and spring chinook salmon (Oncorhynchus tshawytscha). Eight temperatures increasing from 3.9 to 23.3 C (39 to 74 F) by increments of 2.8 C (5 F) were studied. Fish were infected by the direct contact method whereby a suspension of the pathogen was added to the water. It was found that at temperatures of 9.4 C (49 F) and below, no deaths due to the experimental infection with F. columnaris occurred. At 12.2 C (54 F) mortality varied from 4 to 20% among the three species, and increased progressively with increasing temperature to 100% in steelhead trout and coho salmon at 20.5 C (69 F), and 70% in chinook salmon at that temperature. With all three salmonid species, an inverse linear relationship was found between water temperature and the log10 of the mean number of days from exposure to death. This means that as the temperature increased above 12.2 C (54 F), the disease process was progressively accelerated, resulting in a minimum time to death at 20.5 or 23.3 C (69 or 74 F) and a maximum at 12.2 C (54 F). The results indicate that under the conditions of these experiments, columnaris disease in salmonids was completely suppressed by water temperatures of 9.4 C (49 F) or below.

Ceratomyxa shasta Noble, 1950 (Myxozoa: Myxosporea) present in the Fraser River system of British Columbia

1983 ◽  
Vol 61 (9) ◽  
pp. 1991-1994 ◽  
Author(s):  
T. E. McDonald
Keyword(s):  
British Columbia ◽  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Drainage Basin ◽  
Coho Salmon ◽  
Cutthroat Trout ◽  
River System ◽  
Salmo Gairdneri ◽  
Fraser River ◽  
Steelhead Trout

An examination of 220 chinook salmon (Oncorhynchus tshawytscha), 84 coho salmon (O. kisutch), 145 steelhead trout (Salmo gairdneri), and 21 cutthroat trout (S. clarki) for Ceratomyxa shasta (Myxozoa: Myxosporea) from 16 localities in the Fraser River drainage, British Columbia, showed that at all sites examined these salmonid species were infected, with a prevalence ranging between 11 and 100%. The study concludes that C. shasta, the causative agent of the salmonid disease ceratomyxosis, is widely distributed in the Fraser drainage basin and discusses these results in relation to proposed fish culture in the region.

Winter habitat preferences of juvenile salmonids in two interior rivers in British Columbia

1986 ◽  
Vol 64 (7) ◽  
pp. 1506-1514 ◽  
Author(s):  
S. Swales ◽  
R. B. Lauzier ◽  
C. D. Levings
Keyword(s):  
British Columbia ◽  
Chinook Salmon ◽  
Coho Salmon ◽  
Habitat Preferences ◽  
Main Channel ◽  
Steelhead Trout ◽  
Winter Habitat ◽  
Main Species ◽  
Juvenile Salmonids ◽  
Side Channels

The winter distribution and abundance of juvenile salmonids was investigated in various main channel and off-channel habitats in the Coldwater and Nicola rivers in the southern interior region of British Columbia. Catches were generally low in all main channel habitats, with coho salmon and steelhead trout being most abundant and chinook salmon and Dolly Varden char being present in smaller numbers. Coho salmon and steelhead trout catches were generally highest in pools with abundant instream and riparian cover. Steelhead trout was the main species in riprap bank protected areas, although catches were generally low. Highest overall catches were recorded in side channels and off-channel ponds, where water temperatures were usually several degrees higher than in the main river. Coho salmon was the main species in the two Coldwater off-channel ponds with overwintering populations of approximately 4000 and 1000 in 1- and 0.1-ha ponds, respectively (0.4–1.5 fish/m2): overwinter survival of coho salmon in the ponds was estimated to be 87 and 54%, respectively. High densities of coho salmon were also recorded in side channels on the Nicola River (1.5–1.8 fish/m2), together with smaller numbers of chinook salmon and steelhead trout (0.2–0.3 fish/m2). Growth in ponds and side channels appeared to be faster than in main channel habitats. We conclude that juvenile salmonids in the rivers investigated showed considerable habitat segregation during the winter. As in coastal rivers, juvenile coho salmon made extensive use of off-channel ponds, while rainbow trout and chinook salmon were generally most abundant in riprap and deep pools containing log debris, respectively.

Is solar radiation responsible for declines in marine survival rates of anadromous salmonids that rear in small streams?

1998 ◽  
Vol 55 (12) ◽  
pp. 2533-2538 ◽  
Author(s):  
Carl Walters ◽  
Bruce Ward
Keyword(s):  
Solar Radiation ◽  
Atlantic Salmon ◽  
Oncorhynchus Mykiss ◽  
Salmo Salar ◽  
Chinook Salmon ◽  
Coho Salmon ◽  
Survival Rates ◽  
Steelhead Trout ◽  
Small Streams ◽  
Marine Survival

There have been profound declines in marine survival rates of steelhead trout (Oncorhynchus mykiss), coho salmon (O. kisutch), chinook salmon (O. tschawytscha), and Atlantic salmon (Salmo salar) since the mid-1980s, and these declines have been particularly acute in sunny regions. We suggest that the problem may originate in freshwater with radiation (e.g., UV-B) damage to metabolic machinery that is expressed during stressful periods of smolting and ocean entry and that progressively worse damage may soon appear as reduction in freshwater survivals as well. This hypothesis can be tested quickly by management agencies by comparing survival rates of hatchery-reared fish with and without radiation protection during rearing.

Differences in Genetic Diversity for Mitochondrial DNA Between Hatchery and Wild Populations of Oncorhynchus

1994 ◽  
Vol 51 (S1) ◽  
pp. 290-297 ◽  
Author(s):  
Jennifer L. Nielsen ◽  
Christina Gan ◽  
W. Kelley Thomas
Keyword(s):  
Mitochondrial Dna ◽  
Chinook Salmon ◽  
Coho Salmon ◽  
Steelhead Trout ◽  
Wild Populations ◽  
Base Pairs ◽  
Chi Square ◽  
Variable Segment ◽  
Polymerase Chain ◽  
Chi Square Analysis

Amplification by the polymerase chain reaction and sequencing of a highly variable segment (199 base pairs) of mitochondrial DNA (mtDNA) in 491 fish from 22 streams and 9 hatcheries revealed 9 mtDNA types in steelhead trout (Oncorhynchus mykiss), 5 types in coho salmon (O. kisutch), and 6 types in chinook salmon (O. tshawytscha). Likelihood chi-square analysis of frequencies of mtDNA types in eight paired comparisons of hatchery and geographically proximate wild populations of Oncorhynchus showed significant differences in mtDNA genotypes. More mtDNA types were found, on average, in contemporary hatchery populations for each species than in geographically proximate wild stocks. Factors potentially leading to genetic differences in hatchery and wild stocks sampled in California were historic introductions of geographically divergent populations into hatchery brood stocks and lack of introgression of geographically divergent genotypes from the hatchery into wild populations.

Changes in Gill Adenosinetriphosphatase Activity Associated with Parr–Smolt Transformation in Steelhead Trout, Coho, and Spring Chinook Salmon

1972 ◽  
Vol 29 (2) ◽  
pp. 167-171 ◽  
Author(s):  
W. S. Zaugg ◽  
L. R. McLain
Keyword(s):  
Atpase Activity ◽  
Chinook Salmon ◽  
Coho Salmon ◽  
Oncorhynchus Kisutch ◽  
Salmo Gairdneri ◽  
Steelhead Trout ◽  
Similar Increase ◽  
Activity Increase ◽  
Fish Hatchery ◽  
Transport Atpase

The average Na+- and K+-stimulated adenosinetriphosphatase (ATPase) activity of microsomes from gills of hatchery-reared coho salmon (Oncorhynchus kisutch) increased from about 12 μmoles ATP hydrolyzed/mg protein per hr during February through mid-April to approximately 24 in mid-May. Larger fish developed higher activities than smaller fish. Hatchery-reared spring chinook salmon (O. tshawytscha) exhibited a similar increase 2–3 weeks earlier.In 2-year-old hatchery-reared steelhead trout (Salmo gairdneri), Na+-, K+-ATPase activities were elevated in some, but not all, smolt-appearing animals. Parr-appearing fish, including maturing males, showed no activity increase. When held in fresh water to July, steelhead smolts lost their silvery color and became more parr-like in appearance, and the previously elevated ATPase activity decreased to near pre-smolt levels. Yearling steelhead held at the laboratory showed a more consistent rise in ATPase activity.The increase in transport ATPase (Na+-, K+-stimulated) activity occurring during parr–smolt transformation is probably a preparatory step for saltwater adaption and may also be closely associated with migratory disposition.L'activité moyenne de l'adénosinetriphosphatase (ATPase) stimulée par Na+ et K+ dans les microsomes des branchies de saumons coho (Oncorhynchus kisutch) élevés en pisciculture augmente de 12 μmoles environ d'ATPase hydrolysée/mg de protéine par h de février à la mi-avril à 24 à la mi-mai. Les gros poissons développent une activité plus grande que les petits. Les saumons chinook de printemps (O. tshawytscha) élevés en pisciculture font preuve d'un accroissement semblable deux à trois semaines avant les saumons coho.

Relation of Water Temperature to Infections of Coho Salmon (Oncorhynchus kisutch), Chinook Salmon (O. tshawytscha), and Steelhead Trout (Salmo gairdneri) with Aeromonas salmonicida and A. hydrophila

1978 ◽  
Vol 35 (1) ◽  
pp. 1-7 ◽  
Author(s):  
W. J. Groberg Jr. ◽  
R. H. McCoy ◽  
K. S. Pilcher ◽  
J. L. Fryer
Keyword(s):  
Water Temperature ◽  
Chinook Salmon ◽  
Coho Salmon ◽  
Oncorhynchus Kisutch ◽  
Infected Fish ◽  
Aeromonas Salmonicida ◽  
Salmo Gairdneri ◽  
Steelhead Trout

Juvenile steelhead trout (Salmo gairdneri), coho salmon (Oncorhynchus kisutch), and spring chinook salmon (O. tshawytscha) were infected by intraperitoneal or intramuscular injection with Aeromonas salmonicida or A. hydrophila at seven temperatures from 3.9 to 20.5 °C. At 3.9 and 6.7 °C, mortality in fish infected with A. salmonicida varied from 2 to 26% among the three salmonid species. At 20.5 °C 93–100% of these animals died within 2 or 3 days; at 6.7 °C or lower the fish survived for 12–23 days. Growth of A. salmonicida in vitro was influenced by temperature in a manner very similar to its influence on the in vivo infection. Comparable experiments with A. hydrophila gave results much like those with A. salmonicida, though some differences were noted. At a temperature of 20.5 °C percent mortality ranged from 64 to 100%. At 9.4 °C or below no deaths attributed to A. hydrophila occurred. Fatally infected fish died more rapidly at the higher temperatures. Key words: Aeromonas salmonicida, A. hydrophila, water temperature, furunculosis, motile aeromonas septicemia, coho salmon, chinook salmon, steelhead trout

Sign in / Sign up

Export Citation Format

Share Document