North American Journal of Fisheries Management 23:1108–1113, 2003 American Fisheries Society 2003 Producing Fluorescent Marks on Atlantic Salmon Fin Rays and Scales with Calcein via Osmotic Induction

• Main Author: Jerre W. Mohler
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 1108
• Subjects: Atlantic salmon
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.618.9860; http://www.fws.gov/northeast/fisherycenter/pdfs/mohler2003.pdf

Abstract.—Calcified tissues of Atlantic salmon in both larval and postscale developmental life stages became labeled with the fluorochrome dye known as calcein in 7 min by sequential im-mersion in salt and calcein solutions. I introduce the term ‘‘osmotic induction’ ’ to describe this process. At 47 d posttreatment, fish that had been exposed to osmotic induction of calcein as nonfeeding larvae exhibited mortality and growth equivalent to that of nonexposed fish (P, 0.05). Atlantic salmon parr (at 5 months posthatch) exposed to osmotic induction of calcein exhibited no mortality during a 120-d posttreatment period. In addition to inducing a calcein mark on fin rays of all larvae and parr, the procedure also produced a distinct calcein mark on scales of parr. A second exposure of parr to osmotic induction 90 d after the first produced a conspicuous 2-band pattern on scales which corresponded to the two separate marking events. Calcein marks are invisible to the unaided eye but were observed without sacrificing the experimental fish by em-ploying a calcein detection device (patent applied for) and fluorescence microscopy. Osmotic induction of calcein marks is a potentially useful technique for batch-marking fish because it greatly reduces the amount of contact time between the fish and marking solution and produces an easily identified mark; this may enable salmon fishery managers and researchers to perform a