Plasma insulin levels during the spawning migration of the pink salmon, Oncorhynchus gorbuscha

• Published in: Journal of Fish Biology
• Main Authors: Plisetskaya, E. M., Donaldson, E. M., Dye, H. M.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1987
• Subjects: Oncorhynchus gorbuscha; Pink salmon
• Online Access: http://dx.doi.org/10.1111/j.1095-8649.1987.tb05210.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1095-8649.1987.tb05210.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1095-8649.1987.tb05210.x

Plasma insulin concentration was measured by homologous radioimmunoassay in male and female pink salmon. Oncorhynchus gorbuscha , during spawning migration in the Fraser and Thompson Rivers, British Columbia. Although the fish ceased feeding prior to entering fresh water, plasma levels of insulin remained stable (males) or even elevated (females) during the final stages of oogenesis and spermatogenesis, decreasing thereafter. Mean concentrations ranged from 0–69 to 1.24 ng ml −1 in males and from 0.33 to 0.88 ng ml −1 in females. At all stages in the anadromous migration where a significant difference in plasma insulin levels between the sexes was observed, males had higher concentrations than females.