Biotic and Abiotic Influences on Corticosteroid Hormone Rhythms in Channel Catfish
- 1 July 1984
- journal article
- Published by Oxford University Press (OUP) in Transactions of the American Fisheries Society
- Vol. 113 (4) , 414-421
- https://doi.org/10.1577/1548-8659(1984)113<414:baaioc>2.0.co;2
Abstract
Plasma‐corticosteroid concentrations in resting channel catfish Ictalurus punctatus held at 21 C varied only slightly during a 24‐hour period; further, increases in hormone concentrations induced by confinement stress were independent of time of day and photoperiod. Temperature strongly affected both resting corticosteroid concentrations and the dynamics of hormone secretion when fish were stressed. Resting concentrations were greatest in fish acclimated to 5 and 10 C (25–29 ng/ml), sharply lower in fish held at 15, 20, or 21 C (5–9 ng/ml), and intermediate in fish maintained at 25, 30, or 35 C (12–13 ng/ml). Hormone concentrations increased when fish were stressed by confinement. Corticosteroid concentrations hardly changed in fish held at 5 or 10 C, but increased markedly in fish at higher temperatures; in addition the response was more delayed at the lower temperatures.This publication has 0 references indexed in Scilit: