Authors
Conceição, L. E. C.
Advisor(s)
Abstract(s)
Physiological responses after an acute handling stress and their subsequent effects on innate immune
parameters, plasma free amino acids (AA) and liver energy substrates were assessed in Senegalese sole (Solea
senegalensis). Eight groups of six specimens (136.1± 58.4 g wet weight) were maintained undisturbed, while
other eight groups of six specimens were used for acute stress challenge (air exposed during 3 min). A group
of six specimens was sampled for blood and head-kidney collection immediately after air exposure (time 0),
while the remaining groups were sampled at 5 and 30 min, 1, 2, 4, 6 and 24 h. Undisturbed fish were sampled
at the same times and used as control. Fish were fasted for 24 h prior to air exposure and sampling. Plasma
cortisol, glucose, lactate and osmolality levels increased immediately after stress peaking at 1 h in air exposed
fish. Changes in plasma free AA were also observed at 1 and 24 h after stress. In liver, glycogen levels
significantly decreased at 30 min and 1 h, while triglycerides values significantly increased at 1, 2 and 4 h in
air exposedfish. In addition, total AA levels in liver augmented significantly at 2 h holding high until 24 h in air
exposed specimens. The respiratory burst of head-kidney leucocytes from air exposed fish was significantly
higher than that from control groups at 2 and 6 h after air exposure. On the other hand, plasma lysozyme
activity significantly decreased at 4 h after acute stress in air exposed fish, while plasma alternative
complement pathway followed an inverse linear relationship with respect to cortisol showing the lowest
value at 1 h after air exposure. The present study suggests that Senegalese sole presents a stress response
comparable to that observed in other teleosts. While some indispensable AA may be used for the synthesis of
compounds related to the stress response or fatty acid transport, dispensable AA were probably mainly
employed either as energy sources or in gluconeogenesis. Moreover, results from non-specific immune
parameters assessed suggest that cortisol may act as regulator of the innate immune system.
Description
Keywords
Citation
Costas, B.; Conceição, L.E.C.; Aragão, C.; Martos, J.A.; Ruiz-Jarabo, I.; Mancera, J.M.; Afonso, A.Physiological responses of Senegalese sole (Solea senegalensis Kaup, 1858) after stress challenge: Effects on non-specific immune parameters, plasma free amino acids and energy metabolism, Aquaculture, 316, 1-4, 68-76, 2011