TY - JOUR
T1 - Long-term mild hypoxia does not reduce thermal tolerance or performance of the freshwater prawn Macrobrachium tenellum
AU - Tremblay, Nelly
AU - García-Guerrero, Marcelo
AU - Díaz, Fernando
AU - Caamal-Monsreal, Claudia
AU - Rodríguez-Fuentes, Gabriela
AU - Paschke, Kurt
AU - Gebauer, Paulina
AU - Rosas, Carlos
N1 - Publisher Copyright:
© 2021 John Wiley & Sons Ltd.
PY - 2022/1
Y1 - 2022/1
N2 - The present study was designed to assess the performance of the freshwater prawn Macrobrachium tenellum in optimal and sub-optimal dissolved oxygen conditions, considering increasing environmental pressures. Thermal tolerance and thermal metabolic scope (TMS) with related integrated biomarker response (IBR) were measured in prawns exposed to normoxia (80% air saturation), mild (40% air saturation) and severe hypoxia (25% air saturation) at three exposure time points (10, 20 and 30 days). Effects of hypoxia on thermal tolerance were not detectable over time; they were perhaps masked by hyperventilation, or by an increase or diversion of haemolymph processes. After 30 days, TMS was 11% higher in mild hypoxia compared with normoxia, while it was 64% lower in severe hypoxia, indicating the loss of aerobic metabolism capacity during the latter. Mild-hypoxia prawns maintained a high IBR over time, supported by antioxidant enzyme activities (mainly superoxide dismutase), which helped avoid the serious oxidative damage (proteins and lipids) seen in severe hypoxia animals, as well as lower acetylcholinesterase activity that indicated failure of communication between the nervous and locomotor systems. Our results documented a high tolerance by M. tenellum to mild-hypoxia events, which should be further tested under seasonal and extreme habitat/tank temperatures.
AB - The present study was designed to assess the performance of the freshwater prawn Macrobrachium tenellum in optimal and sub-optimal dissolved oxygen conditions, considering increasing environmental pressures. Thermal tolerance and thermal metabolic scope (TMS) with related integrated biomarker response (IBR) were measured in prawns exposed to normoxia (80% air saturation), mild (40% air saturation) and severe hypoxia (25% air saturation) at three exposure time points (10, 20 and 30 days). Effects of hypoxia on thermal tolerance were not detectable over time; they were perhaps masked by hyperventilation, or by an increase or diversion of haemolymph processes. After 30 days, TMS was 11% higher in mild hypoxia compared with normoxia, while it was 64% lower in severe hypoxia, indicating the loss of aerobic metabolism capacity during the latter. Mild-hypoxia prawns maintained a high IBR over time, supported by antioxidant enzyme activities (mainly superoxide dismutase), which helped avoid the serious oxidative damage (proteins and lipids) seen in severe hypoxia animals, as well as lower acetylcholinesterase activity that indicated failure of communication between the nervous and locomotor systems. Our results documented a high tolerance by M. tenellum to mild-hypoxia events, which should be further tested under seasonal and extreme habitat/tank temperatures.
KW - cell stress markers
KW - critical thermal limits
KW - metabolic scope
KW - metabolites
KW - oxygen consumption
UR - http://www.scopus.com/inward/record.url?scp=85113489301&partnerID=8YFLogxK
U2 - 10.1111/are.15553
DO - 10.1111/are.15553
M3 - Artículo
AN - SCOPUS:85113489301
SN - 1355-557X
VL - 53
SP - 63
EP - 74
JO - Aquaculture Research
JF - Aquaculture Research
IS - 1
ER -