Osmoregulation in Penaeus monodon: effects of molting and external salinity.
Abstract
The effect of molting on osmotic, chloride, calcium and total protein concentrations in the hemolymph of the shrimp Penaeus monodon was investigated. Regardless of medium salinity, tissue water as well as osmotic and chloride concentrations in the hemolymph became stable within one day after molting. In general, total protein concentrations remained stable throughout the molting cycle. Large fluctuations in hemolymph calcium were observed 0-6 hours after molt. In low salinities, hemolymph calcium peaked at 3 hours postmolt to values 30% higher than those during molt. These values subsequently decreased rapidly one after molting, when hemolymph concentrations achieved intermolt values. At 44 ppt, calcium concentrations were highest during molt, then gradually declined by about 15% to intermolt values.
Source
In: Maclean, J.L., Dizon, L.B., Hosillos, L.V. (eds.) The First Asian Fisheries Forum. Proceedings of the First Asian Fisheries Forum, 26-31 May 1986, Manila, Philippines. Manila, Philippines: Asian Fisheries Society. pp. 637-640
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Effect of different sizes of saline red tilapia hybrid Oreochromis niloticus Linnaeus x O. mossambicus Peters on the growth of luminous bacteria Vibrio harveyi
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Article
Responses of intermolt Penaeus indicus to large fluctuations in environmental salinity
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