Data/hora: 07/06/2024 09:28:44

Provedor de dados: 	5	
País: 	France	
Título: 	Combined effect of temperature and salinity on osmoregulation of juvenile and subadult Penaeus stylirostris	
Autores: 	Lemaire, Pierrette; Bernard, Eric; Martinez-paz, J; Chim, Liet.	
Data: 	2002-06	
Ano: 	2002	
Palavras-chave: 	Temperature; Salinity; Osmoregulatory capacity; Penaeus stylirostris; Shrimp.	
Resumo: 	In New Caledonia, the "syndrome 93," which results in mass mortalities of farmed shrimp Penaeus stylirostris, occurs during the transitional and the cold seasons. The transitional season is characterized by an important fall in the average water temperature from 28 to 19 degreesC in 2 weeks. Besides this marked temperature fall, there are also nyctemeral temperature changes of up to 7 degreesC in 12 h. The cold season is characterized by an average water temperature of 19 degreesC with extreme lows of 14 degreesC. The objective of this study was to determine the effect of temperature and its variations on the osmoregulatory capacity of juvenile (7-10 g average weight) and subadult (25 g average weight) shrimps subjected to conditions of different salinity. A reduction in temperature level resulted in a decreased osmoregulatory capacity (OC) (defined as the difference between the osmolality of the haemolymph and that of sea water) at low salinity (hyper-CO) and at high salinity (hypo-CO), respectively, below and above the isoosmotic point (26.2 ppt). In subadult shrimps, the hyper-CO was affected when temperature dropped from 26 to 22 degreesC. The hypo-CO was modified only when temperature decreased down to 15 degreesC. Furthermore, the sensitiveness of osmoregulation to temperature changes was dependent on the developmental stage of the shrimp. Subadults were more sensitive than juvenile animals.   The value of the isoosmotic point, which did not depend on the shrimp developmental stage, increased when temperature decreased to 17 or 15 degreesC.   Our results provide an additional explanation of the "syndrome 93" and display the unfavourable influence of marked temperature drop on shrimp health. Our research could provide a possibility of seeking a nutritional and/or genetic solution to improve the capacity of the shrimps to maintain their homeostasis within a rearing medium with fluctuating temperatures.	
Tipo: 	Text	
Idioma: 	Inglês	
Identificador: 	http://archimer.ifremer.fr/doc/2002/publication-395.pdf

DOI:10.1016/S0044-8486(01)00756-6	
Editor: 	Elsevier	
Relação: 	http://archimer.ifremer.fr/doc/00000/395/	
Formato: 	application/pdf	
Fonte: 	Aquaculture (0044-8486) (Elsevier), 2002-06 , Vol. 209 , N. 1-4 , P. 307-317	
Fonte: 	2002 Elsevier Science B.V. All rights reserved