The physiological stress response to acute thermal exposure inBlack Sea trout (Salmo trutta labrax Pallas, 1814)

Abstract

In this study, we aimed to investigate the acute stress responses of Black Sea trout to acute thermal fluctuations. Black Sea trout (184.22 g mean weight) were transferred from a private trout farm to a research center and restocked in a fiberglass square tank. After acclimation to culture conditions (at a water temperature of 15 °C) for 2 weeks, the fish in the experiment were exposed to 25 °C water temperature for 30 min, and the stress responses of the fish were examined at 1, 3, 6, 12, 24, 36, 48, and 72 h. After acute thermal shock, cortisol and glucose levels increased during the first hour in the experimental group. However, cortisol and glucose levels returned to their normal values after 6 and 36 h, respectively. Lysozyme activity decreased at 3 h and rose to its normal level at 12 h after the experiment. Total protein and serum ion concentrations were also affected and fluctuated due to acute thermal stress. Short-term acute thermal exposure also caused a serum ionic imbalance in the trout, but homeostasis was restored at 72 h.

Acclimation to higher temperature and feeding on antioxidants supplemented diets improved Rainbow trout (Oncorhynchus mykiss) resilience to heatwaves

“…The higher levels of total protein in treatments receiving organic selenium supplement in 28°C shock may indicate sh's ability to maintain the homeostasis of total protein content against environmental stress (Pacitti et al, 2016). The organic selenium in the sh diet also increased albumin production in the liver at 20°C, which aligns with the result of other studies (Abdel-tawwab et al, 2007; Dengiz Balta et al, 2017;Mansour et al, 2017). A higher level of selenium micronutrient also plays a vital role in the stability of proteins (Schrauzer, 2003;Sahin et al, 2014).…”

Acclimation to higher temperature and antioxidant supplemented diets improved rainbow trout (Oncorhynchus mykiss) resilience to heatwaves

“…The higher levels of total protein observed in treatments receiving organic selenium supplement in 28 °C shock suggests fish's ability to maintain the homeostasis of total protein content against environmental stress 22 . The organic selenium in the fish diet also increased albumin production in the liver at 20 °C, which aligns with the results of other studies [39][40][41] . A higher level of selenium micronutrient also plays a vital role in the stability of proteins 12,17 .…”

Temperature increase and its effects on fish stress physiology in the context of global warming

“…Secondary stress responses are also observed on acute temperature increase; glucose and lactate generally rise during acute thermal challenge, along with alterations in blood osmolality and other haematological variables (Bard & Kieffer, 2019; Dengiz Balta et al ., 2017). In addition, inhibitory effects on the fish immune system may be observed (Dengiz Balta et al ., 2017). At the cellular level, heat shock protein (HSPs) release is also modulated by the endocrine stress systems (Currie et al ., 2008; Maloyan & Horowitz, 2002).…”

“…First, the synthesis, release and actions of stress hormones are expected to be affected by temperature as a result of general thermodynamic effects on chemical reaction kinetics, according to the Boltzmann–Arrhenius model (Arrhenius, 1915; Boltzmann, 1972). In addition, a severe temperature increase can be a stressor in itself (Dengiz Balta et al ., 2017; Samaras et al ., 2018). Finally, acute or prolonged exposure to warm temperatures can alter the function of the stress axes and responses to further stressors, possibly compromising the long‐term coping capacity of the animal.…”