Osmotic and ionic changes in Taiwan abalone Haliotis diversicolor supertexta at different salinity levels

Abstract

Osmotic and ionic changes in Taiwan abalone Haliotis diversicolor supertexta (5.4 +/- 0.28 cm) were investigated after they were transferred individually from 33 practical salinity unit (psu) to 23, 28, 33 and 38 psu after 0,25, 0.5, 1, 2, 3, 6 and 9 days. Hemolymph osmolality of abalone stabilized within 2 days after they were transferred to different salinities from 33 psu. Hemolymph osmolality, Cl-, Na+ and K+ concentrations increased directly with medium salinity, Hemolymph osmolality was 652, 789, 945 and 1103 mOsm kg(-1) for the abalone transferred to 23, 28, 33 and 38 psu, respectively. Hemolymph Cl- was 275, 323, 365, 409 mmol l(-1), hemolymph Na+ was 312, 376, 465, 569 mmol l(-1) and hemolymph K+ was 8.2, 10.1, 11.9, 12.8 mmol l(-1) for the abalone transferred to 23, 28, 33, 38 psu, respectively. It is concluded that H. diversicolor supertexta are hypo-conformic and hypo-ionic with respect to Cl- and Na+, but hyper-ionic with respect to K+ over ambient media in salinity ranges of 23-38 psu. (C) 2002 Elsevier Science B.V. All rights reserved.