The tissue localization of Aeromonas salmonicida in rainbow trout, Salmo gairdneri Richardson, following three methods of administration

The localization of a live, and a formalized vaccine preparation of Aeromonas salmonicida within the tissues of rainbow trout, Salmo gairdneri , was followed over a 5 day period. When presented by intraperitoneal injection, both the live bacteria and the vaccine localized in the spleen, liver, kidney and gut. When presented orally, the bacteria and the vaccine were confined almost exclusively to the gut region. Direct immersion resulted in low detectable levels within the tissues, with the spleen and kidney localizing the Aeromonas after its initial attachment to the outer surfaces of the fish.