A Technique for Prolonged Blood Sampling in Free-Swimming Salmon

Abstract

A technique is described for insertion of a cannula in the dorsal aorta of salmon for long-term blood sampling or vascular injection while the fish is confined, but free-swimming. Previous methods for single injections into the dorsal aorta are improved by a modified cannulation technique. The practicality of the technique was tested by introducing Evans Blue (T-1824) into the dorsal aorta of immature pink salmon (Oncorhynchus gorbuscha) in sea water and mature sockeye salmon (O. nerka) in fresh water to make preliminary estimates of blood volumes. It was shown that the technique can also be applied to angiography of salmon.