Response of the blue shrimp Litopenaeus stylirostris to temperature decrease and hypoxia in relation to molt stage

Type Article
Date 2005-02
Language English
Author(s) Mugnier Chantal1, Soyez Claude2
Affiliation(s) 1 : IFREMER, Lab Aquaculture Caledonien, Noumea 98846, New Caledonia.
2 : IFREMER, Lab Aquaculture Trop, Tatavao, Tahiti, Fr Polynesia.
Source Aquaculture (0044-8486) (Elsevier), 2005-02 , Vol. 244 , N. 1-4 , P. 315-322
DOI 10.1016/j.aquaculture.2004.11.010
WOS© Times Cited 24
Keyword(s) Temperature, Stress, Penaeid shrimp, Osmoregulation, Molt stage, Litopenaeus stylirostris, Hypoxia
Abstract The effect of different levels of dissolved oxygen (DO) and a decreased temperature combined with severe hypoxia were studied in the blue shrimp Litopenaeus stylirostris in relation to molt stage. In the first experiment, shrimps were submitted to DO concentrations of 5 to 1 mg l(-1). Osmoregulatory capacity (OC) was measured in shrimps at molt stage C after 6, 24, or 48 h of exposure. No mortality was recorded but a significant negative effect of DO concentration on hypo-OC was observed for DO concentrations below 3 mg l(-1). Osmoregulation improved after 48 h exposure, compared to 6 and 24 h exposure.

In a second experiment, temperature was decreased from 28 to 22 degreesC in 24 h, before a severe hypoxia of 0.5+/-0.1 mg O-2 l(-1) was applied. Mortality and OC were studied in relation to molt stages. Half of the shrimps died after respectively 100 min at 0.5 mg O-2 l(-1) at 28 degreesC and 153 min at 0.4 mg O-2 l(-1) at 22degreesC. Mortality was significantly higher in stages D-2 and B compared to stages C and Do. Control shrimps in stage D2 had a lower hypo-OC than shrimps in stages C and Do both at 28 and 22 degreesC. Temperature decrease had no effect on hypo-OC. Hypoxia reduced hypo-OC for all stages, whatever the temperature, but the effect was greater in stage C at 27 degreesC (68% decrease) compared to 22 degreesC (49%) and stage D-2 at both temperatures (respectively, 43% and 58% at 27 and 22 degreesC). Combination of temperature and hypoxia had a significant effect on hypo-OC. Low temperature reduced the effect of hypoxia presumably by slowing down the metabolism. Results are discussed in relation to pond observation. (C) 2004 Elsevier B.V. All rights reserved.
Full Text
File Pages Size Access
publication-372.pdf 14 126 KB Open access
Top of the page