Effects of premature seawater transfer and fasting on plasma growth hormone levels of yearling coho salmon (Oncorhynchus kisutch) parr

Vladimir S. Varnavsky, Tatsuya Sakamoto, Tetsuya Hirano

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

The influence of starvation and premature seawater transfer on plasma growth hormone (GH) concentration in yearling coho salmon parr, was studied. Juveniles were separated into four groups: (1) unfed fish in fresh water (FW), (2) fed fish in FW, (3) unfed fish in sea water (SW) (24%.), (4) fed fish in SW. Plasma sodium concentration, GH and cortisol levels were analyzed after 0, 1, 3, 4, 5 weeks of exposure. Hypoosmoregulatory ability seemed to be impaired after long-term exposure of the juveniles to SW: after 5 weeks, plasma sodium concentrations in SW groups were significantly higher than those in FW groups. The cortisol levels increased slightly in response to transfer from FW to SW as well as to starvation. Plasma GH levels were elevated in unfed FW fish but not in unfed SW fish after 3, 4, and 5 weeks of starvation. In fed SW groups, the increase of plasma GH levels was greater than that of the unfed FW groups. Analysis of variances of plasma GH levels showed the influence of salinity to be greater than that of fasting. It is suggested that the main reason for the high GH levels in 'stunted' salmon may arise from premature transfer to SW rather than from starvation.

Original languageEnglish
Pages (from-to)141-145
Number of pages5
JournalAquaculture
Volume135
Issue number1-3
DOIs
Publication statusPublished - Oct 1 1995
Externally publishedYes

Fingerprint

fasting
parr
Oncorhynchus kisutch
yearlings
somatotropin
hormone
seawater
plasma
starvation
fish
freshwater fish
water
cortisol
sodium
effect
chronic exposure
variance analysis
fish feeds
salmon
analysis of variance

Keywords

  • Oncorhynchus kisutch
  • Plasma growth hormone

ASJC Scopus subject areas

  • Aquatic Science

Cite this

Effects of premature seawater transfer and fasting on plasma growth hormone levels of yearling coho salmon (Oncorhynchus kisutch) parr. / Varnavsky, Vladimir S.; Sakamoto, Tatsuya; Hirano, Tetsuya.

In: Aquaculture, Vol. 135, No. 1-3, 01.10.1995, p. 141-145.

Research output: Contribution to journalArticle

@article{c2cfe52d7ee4437bbcd247b098f6b4ce,
title = "Effects of premature seawater transfer and fasting on plasma growth hormone levels of yearling coho salmon (Oncorhynchus kisutch) parr",
abstract = "The influence of starvation and premature seawater transfer on plasma growth hormone (GH) concentration in yearling coho salmon parr, was studied. Juveniles were separated into four groups: (1) unfed fish in fresh water (FW), (2) fed fish in FW, (3) unfed fish in sea water (SW) (24{\%}.), (4) fed fish in SW. Plasma sodium concentration, GH and cortisol levels were analyzed after 0, 1, 3, 4, 5 weeks of exposure. Hypoosmoregulatory ability seemed to be impaired after long-term exposure of the juveniles to SW: after 5 weeks, plasma sodium concentrations in SW groups were significantly higher than those in FW groups. The cortisol levels increased slightly in response to transfer from FW to SW as well as to starvation. Plasma GH levels were elevated in unfed FW fish but not in unfed SW fish after 3, 4, and 5 weeks of starvation. In fed SW groups, the increase of plasma GH levels was greater than that of the unfed FW groups. Analysis of variances of plasma GH levels showed the influence of salinity to be greater than that of fasting. It is suggested that the main reason for the high GH levels in 'stunted' salmon may arise from premature transfer to SW rather than from starvation.",
keywords = "Oncorhynchus kisutch, Plasma growth hormone",
author = "Varnavsky, {Vladimir S.} and Tatsuya Sakamoto and Tetsuya Hirano",
year = "1995",
month = "10",
day = "1",
doi = "10.1016/0044-8486(95)01001-7",
language = "English",
volume = "135",
pages = "141--145",
journal = "Aquaculture",
issn = "0044-8486",
publisher = "Elsevier",
number = "1-3",

}

TY - JOUR

T1 - Effects of premature seawater transfer and fasting on plasma growth hormone levels of yearling coho salmon (Oncorhynchus kisutch) parr

AU - Varnavsky, Vladimir S.

AU - Sakamoto, Tatsuya

AU - Hirano, Tetsuya

PY - 1995/10/1

Y1 - 1995/10/1

N2 - The influence of starvation and premature seawater transfer on plasma growth hormone (GH) concentration in yearling coho salmon parr, was studied. Juveniles were separated into four groups: (1) unfed fish in fresh water (FW), (2) fed fish in FW, (3) unfed fish in sea water (SW) (24%.), (4) fed fish in SW. Plasma sodium concentration, GH and cortisol levels were analyzed after 0, 1, 3, 4, 5 weeks of exposure. Hypoosmoregulatory ability seemed to be impaired after long-term exposure of the juveniles to SW: after 5 weeks, plasma sodium concentrations in SW groups were significantly higher than those in FW groups. The cortisol levels increased slightly in response to transfer from FW to SW as well as to starvation. Plasma GH levels were elevated in unfed FW fish but not in unfed SW fish after 3, 4, and 5 weeks of starvation. In fed SW groups, the increase of plasma GH levels was greater than that of the unfed FW groups. Analysis of variances of plasma GH levels showed the influence of salinity to be greater than that of fasting. It is suggested that the main reason for the high GH levels in 'stunted' salmon may arise from premature transfer to SW rather than from starvation.

AB - The influence of starvation and premature seawater transfer on plasma growth hormone (GH) concentration in yearling coho salmon parr, was studied. Juveniles were separated into four groups: (1) unfed fish in fresh water (FW), (2) fed fish in FW, (3) unfed fish in sea water (SW) (24%.), (4) fed fish in SW. Plasma sodium concentration, GH and cortisol levels were analyzed after 0, 1, 3, 4, 5 weeks of exposure. Hypoosmoregulatory ability seemed to be impaired after long-term exposure of the juveniles to SW: after 5 weeks, plasma sodium concentrations in SW groups were significantly higher than those in FW groups. The cortisol levels increased slightly in response to transfer from FW to SW as well as to starvation. Plasma GH levels were elevated in unfed FW fish but not in unfed SW fish after 3, 4, and 5 weeks of starvation. In fed SW groups, the increase of plasma GH levels was greater than that of the unfed FW groups. Analysis of variances of plasma GH levels showed the influence of salinity to be greater than that of fasting. It is suggested that the main reason for the high GH levels in 'stunted' salmon may arise from premature transfer to SW rather than from starvation.

KW - Oncorhynchus kisutch

KW - Plasma growth hormone

UR - http://www.scopus.com/inward/record.url?scp=0001223915&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0001223915&partnerID=8YFLogxK

U2 - 10.1016/0044-8486(95)01001-7

DO - 10.1016/0044-8486(95)01001-7

M3 - Article

VL - 135

SP - 141

EP - 145

JO - Aquaculture

JF - Aquaculture

SN - 0044-8486

IS - 1-3

ER -