Effects of cortisol and salinity challenge on water balance in developing larvae of tilapia (Oreochromis mossambicus)

L. Y. Lin, C. F. Weng, P. P. Hwang

Research output: Contribution to journalReview article

21 Citations (Scopus)


Effects of exogenous cortisol on drinking rate and water content in developing larvae of tilapia (Oreochromis mossambicus) were examined. Both freshwater- and seawater-adapted larvae showed increases in drinking rates with development. Drinking rates of seawater-adapted larvae were about four- to ninefold higher than those of freshwater-adapted larvae from day 2 to day 5 after hatching. Seawater-adapted larvae showed declines in drinking rate and water content at 4 and 14 h, respectively, after immersion in 10 mg L-1 cortisol. In the case of freshwater-adapted larvae, the drinking rate decreased after 8 h of cortisol immersion, while the water content did not show a significant change even after 32 h of cortisol immersion. In a subsequent experiment of transfer from freshwater to 20 ppt (parts per thousand, salinity) seawater, immersion in 10 mg L-1 cortisol for 8-24 h enhanced the drinking rate in larvae at 4 h after transfer, but no significant difference was found in water contents between cortisol-treated and control groups following transfer. These results suggest that cortisol is involved in the regulation of drinking activity in developing tilapia larvae.

Original languageEnglish
Pages (from-to)283-289
Number of pages7
JournalPhysiological and Biochemical Zoology
Issue number3
Publication statusPublished - 2000 Sep 11


ASJC Scopus subject areas

  • Physiology
  • Biochemistry
  • Animal Science and Zoology

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