Synergistic and antagonistic effects of thermal shock, air exposure, and fishing capture on the physiological stress of Squilla mantis (Stomatopoda)

PLoS One. 2014 Aug 18;9(8):e105060. doi: 10.1371/journal.pone.0105060. eCollection 2014.

Abstract

This study is aimed at assessing the effects of multiple stressors (thermal shock, fishing capture, and exposure to air) on the benthic stomatopod Squilla mantis, a burrowing crustacean quite widespread in the Mediterranean Sea. Laboratory analyses were carried out to explore the physiological impairment onset over time, based on emersion and thermal shocks, on farmed individuals. Parallel field-based studies were carried out to also investigate the role of fishing (i.e., otter trawling) in inducing physiological imbalance in different seasonal conditions. The dynamics of physiological recovery from physiological disruption were also studied. Physiological stress was assessed by analysing hemolymph metabolites (L-Lactate, D-glucose, ammonia, and H+), as well as glycogen concentration in muscle tissues. The experiments were carried out according to a factorial scheme considering the three factors (thermal shock, fishing capture, and exposure to air) at two fixed levels in order to explore possible synergistic, additive, or antagonistic effects among factors. Additive effects on physiological parameters were mainly detected when the three factors interacted together while synergistic effects were found as effect of the combination of two factors. This finding highlights that the physiological adaptive and maladaptive processes induced by the stressors result in a dynamic response that may encounter physiological limits when high stress levels are sustained. Thus, a further increase in the physiological parameters due to synergies cannot be reached. Moreover, when critical limits are encountered, mortality occurs and physiological parameters reflect the response of the last survivors. In the light of our mortality studies, thermal shock and exposure to air have the main effect on the survival of S. mantis only on trawled individuals, while lab-farmed individuals did not show any mortality during exposure to air until after 2 hours.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Air*
  • Animals
  • Crustacea / metabolism*
  • Crustacea / physiology
  • Glucose / metabolism
  • Glycogen / metabolism
  • Mediterranean Sea
  • Stress, Physiological / physiology
  • Temperature

Substances

  • Glycogen
  • Glucose

Grants and funding

This work was financially supported by Regione Veneto "Progetto Clodia", MURST (ex-60%), Co-funded by the FP7 EU project GAP2 (Bridging the gap between science, stakeholders and policy makers), Grant agreement no.: 266544, and ISPRA. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.