Abstract

This study was undertaken to assess dorsal aorta cannulation as a method to evaluate alterations in diet composition and feeding protocol on pigment retention in salmonid fish. Temporal changes in blood astaxanthin concentrations of dorsal aorta-cannulated Atlantic salmon, Salmo salar L., were followed in relation to variations in dietary pigment concentration and fish-feeding husbandry protocol.The fish were held individually in 200-L fibreglass tanks supplied with running sea water. Each fish was forced to swim at 0.5 body lengths s(-1) and was fed daily by hand to satiation. The fish had an average growth rate of 1% day(-1). Blood astaxanthin concentrations were noted to be highly correlated (r = 0.995) with dietary levels of astaxanthin, but not as well correlated (r = 0.71) with total gut content of this pigment. Marked variations in blood astaxanthin concentration were noted between individual fish at each dietary pigment concentration, but the ranking of the fish was generally unaffected between each dietary pigment level. After cessation of feeding a diet supplemented with 75 mg of astaxanthin kg(-1), salmon fed a diet with no pigment showed more-rapid blood pigment clearance than those that were starved. Likely, feed remaining in the alimentary tract of the starved fish functioned as a reservoir of pigment for the blood until the intestinal tract was empty. Blood pigment levels were not depressed in salmon fed a diet supplemented with 75 mg of astaxanthin kg(-1) once daily instead of twice daily.

Keywords

astaxanthin; Atlantic salmon; cannulation; carotenoids; dorsal aorta; salmonids; Salmo salar

Published in

Aquaculture Nutrition
1995, Volume: 1, number: 1, pages: 43-50
Publisher: WILEY-BLACKWELL

SLU Authors

• Kiessling, Anders

  • Department of Molecular Sciences, Swedish University of Agricultural Sciences
    
  • Fisheries and Oceans Canada (DFO)

UKÄ Subject classification

Fish and Aquacultural Science
Zoology


Publication identifier

DOI: https://doi.org/10.1111/j.1365-2095.1995.tb00034.x

Permanent link to this page (URI)

https://res.slu.se/id/publ/80500