Effect of salinity and temperature on salinity tolerance of the sea cucumber Apostichopus japonicus

Abstract

Sea cucumber Apostichopus japonicus juveniles acclimated to different environmental conditions (23, 25, and 27°C combined with 25, 30, and 35 psu) were assessed for tolerance to increasing and decreasing levels of salinity at a rate of 2 psu h -1 . They were also tested for the LS 50 (median lethal salinity) when transferred directly into a series of higher salinity (32-46 psu) and lower salinity (9-25 psu). The CSMax (critical salinity maximum), CSMin (critical salinity minimum), USTL (upper salinity tolerance limit), and LSTL (lower salinity tolerance limit) were positively correlated to the acclimated salinity level but negatively correlated to temperature. The CSMax of A. japonicus was 6.2-10.0 psu higher than the USTL, and the CSMin was 5.5-8.5 psu lower than the LSTL, indicating that gradual changes in salinity resulted in the wide range of salinity tolerance that was observed, but that abrupt changes in salinity resulted in the narrow range of tolerance. Two-way analysis of variance revealed that salinity and temperature had a significant effect on 50% CSMax, 50% CSMin, USTL, and LSTL (P \ 0.001). The information obtained in this study will be valuable for the further development of the sea cucumber aquaculture industry in China.

Multigenerational analysis of temperature and salinity variability affects on metabolic rate, generation time, and acute thermal and salinity tolerance in Daphnia pulex

“…In the shrimp, Litopenaeus vannamei, thermal tolerance was increased by the combined effects of acclimation temperature and salinity (Kumlu et al, 2010), though acclimation temperature had a stronger influence than salinity on thermal tolerance. In contrast, in the sea cucumber, Apostichopus japonicus, salinity tolerance limits were positively affected by acclimation to increased salinity, but negatively affected by acclimation to increased temperature (Hu et al, 2010). The simultaneous effects of temperature and salinity acclimation have not been demonstrated for Daphnia, though salinity has been shown to alter Daphnia tolerance limits to other stressors, such as heavy metals (Bossuyt et al, 2005).…”

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“…Several authors have reported that temperature had significant effects on survival rate and also associated with salinity. 100% survival rate was reported at 23, 27, 25°C for normal salinity of sea water for A. japonicus (Hu et al, 2010). Chu Yuan kee et al (2007) found that, B. marmorata displayed 100% survival rate at salinity 25 and 35 ppt and 91,67% and 66,65% survival rates in temperature 28 and 32°C, respectively.…”

“…Therefore, researches on sea cucumber rearing especially in the Far East and Asian countries has been considered more and more. There are plenty of studies focused on physicochemical parameters effects on growth of tropical sea cucumbers (Hamel and Mercier, 1996;Kashenko, 2002;Asha ve Muthiah, 2005;Wang et al, 2008;Hu et al, 2010). One of the most physicochemical parameter that effecting growth of sea cucumberis the temperature (Dong et al, 2006).…”

Molecular cloning, characterization and expression analysis of a C-type lectin (AJCTL) from the sea cucumber Apostichopus japonicus

“…C-type lectins from other molluscs might follow different evolutionary pathways and play different functions in vivo [30]. In sea cucumber, the innate immune system is particularly important, because echinoderms lack the immune system that is later evolved in vertebrates [24]. The ability to recognize the exposed glycans on the cell surface of potential pathogens by host humoral or cell-associated lectins is considered as a key function of innate immunity and a primary role of PRRs [25,30].…”

“…Hence, there were a number of studies on A. japonicus done in recent years. This sea cucumber is epibenthic and occurs along the coastlines of temperate Asia [24]. It belongs to the Echinodermata, Eleutherozoa, Holothuroidea, Aspidochirota, Stichopodidae, Apostichopus, A. japonicus [25].…”