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Updated: May 6, 2026

Effectiveness of the Air Stripping in Two Salmonid Fish, Rainbow Trout Oncorhynchus Mykiss and Brown Trout Salmo Trutta Morpha fario
Published on: September 16, 2018
Androgen levels and erythrocytosis in maturing brown trout,Salmo trutta L
1Freshwater Biological Association, The Ferry House, Far Sawrey, Ambleside, Cumbria, UK.
Abstract:
The number of circulating erythrocytes was monitored in two strains of brown trout during the spawning season. Erythrocyte numbers were significantly elevated in mature male fish of both strains compared with mature females or immature fish. This period of erythrocytosis coincided with elevated plasma 11-ketotestosterone levels in mature male fish, was out of phase with the testosterone peak in males and was not observed in females despite high levels of plasma testosterone. The results are discussed with reference to the control of erythropoiesis in higher vertebrates.
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