Effects of Pseudobranchectomy on Visual Pigment Density and Ocular PO 2 in Atlantic Salmon, Salmo salar

• Published in: Journal of the Fisheries Research Board of Canada
• Main Authors: Ballintijn, C. M., Beatty, D. D., Saunders, R. L.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1977
• Subjects: General Medicine; Atlantic salmon; Salmo salar
• Online Access: http://dx.doi.org/10.1139/f77-286; http://www.nrcresearchpress.com/doi/pdf/10.1139/f77-286

Bilateral pseudobranchectomy (B.P.) of Atlantic salmon, Salmo salar, resulted in a progressive loss of visual pigment and a marked decrease in ocular PO 2 near the retina. B.P. fish were dark and blind within a few hours of pseudobranchectomy. Unilateral pseudobranchectomy (U.P.) did not have a similar effect on ocular PO 2 or visual pigment density in either the ipsilateral or the contralateral eye. U.P. fish did not become dark or blind. An interconnection exists between the right and left ophthalmic arteries permitting an intact pseudobranch to supply blood to the contralateral eye whose pseudobranch has been removed. Although intramuscular injection of acetazolamide caused an initial decrease in amount of visual pigment, body darkening, and blindness, these effects were not permanent. Acetazolamide also caused a marked decrease in ocular PO 2 similar to that in B.P. fish. In control fish, dorsal aortic blood and ocular PO 2 values were dependent upon an adequate irrigation of the gills. Key words: salmonid, Salmo, pseudobranch, oxygen tension, eye, visual pigment