Coagglutination Test with Antibody-Sensitized Staphylococci for Rapid and Simple Serological Diagnosis of Fish Furunculosis

Abstract

The application of a coagglutination test using staphylococci sensitized with specific antibody for the diagnosis of furunculosis causing by A. salmonicida in salmonids was studied.
This test proved to be a simple, rapid and reliable diagnostic procedure of furunculosis in the field as well as in the laboratory without any special apparatus.
The procedure of this method is summarized as follows;
1) Furuncle or kidney sample from diseased fish is homogenized with nine volumes of PBS, and heated in a boiling water for 30 min.
2) The supernatant is collected after centrifugation at 4000 rpm for 20 min. This may be omitted if a centrifuge is unavailable.
3) One drop of the supernatant and one drop of anit-A. salmonicida antibody-sensitized staphylococci suspension are mixed on a glass slide and incubate at room temperature. The results is read after 30 and 60 min.
4) If positive results was observed by means of the coagglutination test, the existence of A. salmonicida in the same samples which were employed on the coagglutination test should be reconfirmed by using a conventional cultural procedure.