Differences in the responses of two mudskippers,Boleophthalmus boddaerti andPeriophthalmus chrysospilos to changes in salinity
✍ Scribed by Chew, S. F. ;Ip, Y. K.
- Publisher
- John Wiley and Sons
- Year
- 1990
- Tongue
- English
- Weight
- 432 KB
- Volume
- 256
- Category
- Article
- ISSN
- 0022-104X
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
When mudskippers were fully submerged in 100% seawater (SW), the mortality of Boleophthalmus boddaerti was higher than that of Periophthalmus chrysospilos. However, this trend was reversed when mudskippers were submerged in dechlorinated tap water or in 10% SW. The plasma osmolality of P. chrysospilos exposed to 80% SW was significantly higher than that of control fish free to be in or out of 50% SW and that of fish submerged in 10% or 50% SW. The muscle and liver of the fish exposed to 80% SW also contained significantly higher levels of ninhydrin‐positive substances (NPS). In addition, the aminating activity of glutamate dehydrogenase (GDH) in the extracts from the liver and muscle of P. chrysospilos submerged in 80% SW for 7 days was significantly higher than those of fish submerged in 10% SW for the same period. However, the levels of NPS in the muscle and liver of B. boddaerti were unchanged by changes in salinity. Furthermore, the aminating and deaminating activities of GDH in the extracts from the liver and muscle of B. boddaerti, after fish had been submerged in 80% SW for 7 days, were not significantly different from those of fish submerged in 10% SW for a similar period of time. Such differences between the two species of mudskippers in response to changes in salinity may be correlated to the differences in the environmental conditions in their natural habitats.