Development of Antibodies against Aeromonas Salmonicida in Trout¹ Free

The development of agglutinating antibody to Aeronomas salmonicida in brook and brown trout was demonstrated by a tube agglutination and a rapid slide agglutination test. Comparison of agglutinin titer development in rabbits and trout demonstrated that trout have a slow antibody response reaching maximum titer about 3 months after injection. Rabbits developed peak titers within a month after receiving the same dose of antigen. Trout immunized with a single injection of formalin-killed bacteria in a mineral oil adjuvant were protected against intraperitoneal injections of viable Aeromonas salmonicida.