The corticosteroid hormone cortisol is the central mediator of the teleost stress response. Therefore, the accurate quantification of cortisol in teleost fishes is a vital tool for addressing fundamental questions about an animal’s physiological response to environmental stressors. Conventional steroid extraction methods using plasma or whole-body homogenates, however, are inefficient within an intermediate size range of fish that are too small for phlebotomy and too large for whole-body steroid extractions. To assess the potential effects of hatchery-induced stress on survival of fingerling hatchery-reared Spotted Seatrout (Cynoscion nebulosus), we developed a novel extraction procedure for measuring cortisol in intermediately sized fish (50–100 mm in length) that are not amenable to standard cortisol extraction methods. By excising a standardized portion of the caudal peduncle, this tissue extraction procedure allows for a small portion of a larger fish to be sampled for cortisol, while minimizing the potential interference from lipids that may be extracted using whole-body homogenization procedures. Assay precision was comparable to published plasma and whole-body extraction procedures, and cortisol quantification over a wide range of sample dilutions displayed parallelism versus assay standards. Intra-assay %CV was 8.54 %, and average recovery of spiked samples was 102 %. Also, tissue cortisol levels quantified using this method increase 30 min after handling stress and are significantly correlated with blood values. We conclude that this modified cortisol extraction procedure provides an excellent alternative to plasma and whole-body extraction procedures for intermediately sized fish, and will facilitate the efficient assessment of cortisol in a variety of situations ranging from basic laboratory research to industrial and field-based environmental health applications.
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We thank the Thad Cochran Marine Aquaculture staff for help with fish rearing and care. This project was funded by a Gulf of Mexico Energy Security Act (GOMESA) grant from the Mississippi Department of Marine Resources and the Mississippi Department of Marine Resources Tidelands Trust Fund Program.
Avella M, Schreck CB, Prunet P (1991) Plasma prolactin and cortisol concentrations of stressed coho salmon, Oncorhynchus kisutch, in fresh water or salt water. Gen Comp Endocrinol 81:21–27CrossRefPubMedGoogle Scholar
Barcellos LJG, Ritter F, Kreutz LC, Quevedo RM, Silva LB (2007) Whole-body cortisol increases after direct and visual contact with a predator in Zebrafish, Danio rerio. Aquaculture 272:774–778CrossRefGoogle Scholar
Barnett CW, Pankhurst NW (1998) The effects of common laboratory and husbandry practices on the stress response of greenback flounder, Rhombosolea tapirina. Aquaculture 162:313–329CrossRefGoogle Scholar
Barton BA (2002) Stress in fishes: a diversity of responses with particular reference to changes in circulating corticosteroids. Integr Comp Biol 42:517–525CrossRefPubMedGoogle Scholar
Barton BA, Zitzow RE (1995) Physiological responses of juvenile walleyes to handling stress with recovery in saline water. Progress Fish-Cultur 57:267–276CrossRefGoogle Scholar
Barton BA, Schreck CB, Barton LD (1987) Effects of chronic cortisol administration and daily acute stress on growth, physiological conditions, and stress responses in juvenile rainbow trout. Dis Aquat Organ 2:173–185CrossRefGoogle Scholar
Flos R, Reig L, Torres P, Tort L (1988) Primary and secondary stress responses to grading and hauling in rainbow trout, Salmo gairdneri. Aquaculture 71:99–106CrossRefGoogle Scholar
Iwama GK, McGeer JC, Bernier NJ (1992) The effects of stock and rearing density on the stress response in juvenile coho salmon (Oncorhynchus kisutch). ICES Mar Sci Symp 194:67–83Google Scholar
Iwama GK, Pickering AD, Sumpter JP, and Schreck CB (1997) Fish stress and health in aquaculture. Society of experimental biology seminar series 62Google Scholar
Mesa MG (1994) Effects of multiple acute stressors on the predator avoidance ability and physiology of juvenile Chinook salmon. Trans Am Fish Soc 123:786–793CrossRefGoogle Scholar
Mommsen TP, Vijayan MM, Moon TW (1999) Cortisol in teleosts: dynamics, mechanisms of action, and metabolic regulation. Rev Fish Biol Fisheries 9:211–268CrossRefGoogle Scholar
Pankhurst NW, Dedual M (1994) Effects of capture and recovery on plasma levels of cortisol, lactate and gonadal steroids in a natural population of rainbow trout. J Fish Biol 45:1013–1025CrossRefGoogle Scholar
Peterson BC, Booth NJ (2009) Validation of a whole-body cortisol extraction procedure for channel catfish (Ictalurus punctatus) fry. Fish Physiol Biochem 36:661–665CrossRefPubMedGoogle Scholar
Ramsay J, Feist G, Varga Z, Westerfield M, Kent M, Schreck CB (2006) Whole-body cortisol as indicator of crowding stress in adult Zebrafish, Danio rerio. Aquaculture 258:565–574CrossRefGoogle Scholar
Ramsay J, Feist G, Varga Z, Westerfield M, Kent M, Schreck CB (2009) Whole-body cortisol response of Zebrafish to acute net handling stress. Aquaculture 297:157–162PubMedCentralCrossRefPubMedGoogle Scholar
Sink TD, Kumaran S, Lochmann RT (2007) Development of a whole-body cortisol extraction procedure for determination of stress in golden shiners, Notemigonus crysoleucas. Fish Physiol Biochem 33:189–193CrossRefGoogle Scholar
Wendelaar Bonga SE (1997) The stress response in fish. Physiology Reviews 77:591–625Google Scholar