Plasma cortisol and sex steroid levels in great lakes coho salmon (Oncorhynchus kisutch walbaum) in relation to fecundity and egg survival

1985 ◽  
Vol 80 (1) ◽  
pp. 61-68 ◽  
Author(s):  
P.F Morrison ◽  
J.F Leatherland ◽  
R.A Sonstegard
Keyword(s):  
Great Lakes ◽  
Plasma Cortisol ◽  
Coho Salmon ◽  
Oncorhynchus Kisutch ◽  
Sex Steroid ◽  
Egg Survival

Fecundity of Coho Salmon (Oncorhynchus kisutch) from the Great Lakes and a Comparison with Ocean Salmon

1976 ◽  
Vol 33 (5) ◽  
pp. 1150-1155 ◽  
Author(s):  
Thomas M. Stauffer
Keyword(s):  
Great Lakes ◽  
Early Life ◽  
First Generation ◽  
Lake Michigan ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
Lake Superior ◽  
Oncorhynchus Kisutch ◽  
Early Life History ◽  
Freshwater Salmon

I measured fecundity of coho salmon (Oncorhynchus kisutch) that matured in the Great Lakes to make comparisons with Pacific Ocean coho salmon and among groups of Great Lakes salmon. Numbers of eggs produced (1600–3500) by Great Lakes salmon were comparable to production (1500–3300) by Pacific salmon of similar size. Average egg diameters of Lake Michigan (7.1–7.4 mm) and Pacific salmon (6.1–7.4 mm) were also comparable but Lake Superior eggs were smaller (5.1–5.4 mm). Fecundity of second generation freshwater salmon which originated from Lake Michigan eggs was similar to that of the first generation which originated from Pacific eggs because the average numbers (2938–3243) and diameters (7.1–7.4 mm) of eggs produced were about the same. On the average, Lake Michigan salmon contained more (2938) and larger (7.1-mm diam) eggs than did Lake Superior salmon (2150 and 5.1-mm diam) of the same year-class and early life history.

Increasing frequency of thyroid goiters in Coho salmon (Oncorhynchus kisutch) in the Great Lakes

Science ◽  
1977 ◽  
Vol 198 (4315) ◽  
pp. 425-426 ◽  
Author(s):  
R. Moccia ◽  
J. Leatherland ◽  
R. Sonstegard
Keyword(s):  
Great Lakes ◽  
Coho Salmon ◽  
Oncorhynchus Kisutch

Downregulation of corticosteroid receptors in gills of coho salmon due to stress and cortisol treatment

1994 ◽  
Vol 267 (2) ◽  
pp. R432-R438 ◽  
Author(s):  
J. M. Shrimpton ◽  
D. J. Randall
Keyword(s):  
Plasma Cortisol ◽  
Coho Salmon ◽  
Oncorhynchus Kisutch ◽  
Hormone Treatment ◽  
Radioreceptor Assay ◽  
Acute Administration ◽  
Similar Reduction ◽  
Corticosteroid Receptors ◽  
Cortisol Levels ◽  
Cr Concentration

The effect of stress and cortisol treatment on corticosteroid receptors (CRs) in the gills of coho salmon (Oncorhynchus kisutch) was examined. Plasma cortisol levels were elevated acutely by intraperitoneal injection of cortisol 21-hemisuccinate and chronically by implanting miniosmotic pumps filled with cortisol or by repeated daily handling stresses. CR concentration and affinity were measured by radioreceptor assay employing 3H-labeled triamcinolone acetonide as ligand. Acute administration of cortisol resulted in a reduction in CR numbers for 72 h with no change in affinity. Chronic cortisol treatment resulted in a decrease in CR concentration and affinity. The change in affinity occurred only while plasma cortisol levels remained elevated, but CR population remained significantly reduced for at least 10 days after cessation of hormone treatment. Repeated handling stresses resulted in a similar reduction in CR numbers but without an apparent change in affinity. The chronic or repeated elevation in plasma cortisol downregulates the sensitivity of the gills to cortisol by a persistent reduction in CR concentration, despite the return to nonstress levels of circulating cortisol.

Sign in / Sign up

Export Citation Format

Share Document