Immune Response of Juvenile Coho Salmon (Oncorhynchus kisutch) to Aeromonas salmonicida Cells Administered Intraperitoneally in Freund's Complete Adjuvant

Abstract

The antibody response of a population of juvenile coho salmon (Oncorhynchus kisutch) held at 12 C approached 100% following a single parenteral vaccination with Aeromonas salmonicida cells emulsified in Freund's complete adjuvant. This response indicates that coho salmon behave as a homogeneous population with respect to immunological competence.Fish as small as 1.2 g produced antibodies as early as 4 wk after administration of this vaccine; high levels of antibody persisted for at least 1 yr after injection. This single vaccination provided juvenile coho salmon with protective immunity against furunculosis.