Taste Responses in Atlantic Salmon ( Salmo salar) Parr
External receptors located in the snout region of Atlantic salmon parr are innervated by the facial nerve and are differentially sensitive to several chloride salts (NaCl = KCl > MgCl 2 > CaCl 2 ). They are also sensitive to mineral and organic acids but insensitive to uncharged molecules such...
Published in: | Journal of the Fisheries Research Board of Canada |
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Main Authors: | , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Canadian Science Publishing
1970
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Subjects: | |
Online Access: | http://dx.doi.org/10.1139/f70-218 http://www.nrcresearchpress.com/doi/pdf/10.1139/f70-218 |
Summary: | External receptors located in the snout region of Atlantic salmon parr are innervated by the facial nerve and are differentially sensitive to several chloride salts (NaCl = KCl > MgCl 2 > CaCl 2 ). They are also sensitive to mineral and organic acids but insensitive to uncharged molecules such as neutral amino acids and simple sugars.The palatine organ containing taste buds situated on the roof of the mouth is sensitive to strongly ionized as well as uncharged molecules.The two classes of receptors differ in temporal patterns of discharge and in their susceptibility to the blocking agents Hg ++ and Pb ++ and the potentiating agent Cu ++ .Salmon parr can detect Hg ++ in concentrations lower than other divalent cations as judged electrophysiologically; food pellets treated with dilute solutions of Hg ++ are rejected by the fish.As chain length increases in the aliphatic acid series the compounds become increasingly stimulatory as measured by nerve discharges in the palatine nerve.Inert carriers treated with aliphatic acids of increasing chain length become increasingly preferred by salmon, and carriers treated with valeric and caproic acid are ingested.Anosmic fish are capable of discriminating chemically treated carriers in a way similar to fish in which the olfactory organ is intact.The cellular nature of external receptors of the snout is uncertain; the possibility that they are neuromasts is discussed. |
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