A multivariate comparison of the stress response in three salmonid and three cyprinid species: evidence for inter‐family differences

Abstract

The response of six species of freshwater fishes, from the families Cyprinidae (common carp Cyprinus carpio, roach Rutilus rutilus and chub Leuciscus cephalus) and Salmonidae (rainbow trout Oncorhynchus mykiss, brown trout Salmo trutta and Arctic charr Salvelinus alpinus), to a standardized stressor was evaluated. A 6 h period of confinement resulted in changes to plasma cortisol, glucose, amino acid and lactate levels compared with unconfined controls. There were significant differences in the response profiles both within and between families. The cyprinid species exhibited higher and more sustained stress-induced increases in plasma cortisol and glucose than the salmonid species. In cyprinids, plasma lactate and plasma amino acid concentration showed less disturbance following stress than in salmonids. The results of the study, together with an evaluation of previously published data for eight salmonid species and six cyprinid species, support the hypothesis that differences in core elements of the stress response exist between species of fishes, and that this variation may have a systematic basis.

Cortisol and finfish welfare

“…Both basal and stressed cortisol levels differ widely between species, and within a species (Fig. 2), being affected by factors such as temperature, gender, sexual maturity and genetics (Pottinger 2010). Barton (2002) showed that both basal and stressed cortisol levels differed between species of fish exposed to an identical procedure (30 s aerial emersion).…”

“…The main difference between the catecholamines and cortisol is that the release of catecholamines is triggered by nerve circuitry (rather than by a cascade of chemical messengers) so the response is very quick, making it virtually impossible to obtain baseline blood concentration unaffected by the sampling itself. Catecholamines in fish have therefore received much less attention than cortisol but merit greater investigation (Pottinger 2010). …”

“…In contrast to the common view that corticosteroids are immunosuppressive, it has been suggested that acute surges of cortisol may enhance some components of the immune defence mechanism in fish (see Ellis et al 2007b). • the density of, and affinity of receptors in target tissues for stress hormones (Pottinger 2010), will affect the magnitude of the 2°responses, which will then become further moderated at the 3°level. • variability in basal and response levels of cortisol (Fig.…”

Glucocorticoid and mineralocorticoid receptors regulate paracellular permeability in a primary cultured gill epithelium

“…Hormones were dissolved in appropriate solutions and stored as single use stock aliquots at -30°C until use. Cortisol was used at a single dose of 500ngml -1 , which was selected based on the response of cultured trout gill epithelia to cortisol treatment as observed in previous studies (Chasiotis et al, 2010;Kelly and Wood, 2001) as well as levels of cortisol seen in stressed salmonids (see Pottinger, 2010). Deoxycorticosterone and aldosterone were used at doses of 5, 50 and 500ngml -1 and dexamethasone was used at a final concentration of 1.4mmoll -1 (i.e.…”

Stress in Atlantic salmon: response to unpredictable chronic stress

“…Examples include suboptimal/poor water quality, repeated handling, transport and crowding. The effects of many of these challenges have been studied, albeit mostly as a single stressor (Barton and Peter, 1982;Gorissen et al, 2012;Di Marco et al, 2008;Pottinger, 2010;Remen et al, 2012). Studies on mammals (Aguilera and Rabadan-Diehl, 2000;Dhabhar and McEwen, 1997;Grissom and Bhatnagar, 2009;Thorsell et al, 1999), as well as fish (Schreck, 2000), show they have great resilience to a single stressor given repeatedly over long periods of time; however, knowledge on how ectotherms respond to multiple persistent stressors is very scant.…”