Preparation and optimization of rapid and sensitive coagglutination test for detection of infectious pancreatic necrosis virus (IPNV)

Abstract

The aim of this study is the development of a coagglutination test for rapid diagnosis of infectious pancreatic necrosis (IPN) virus which causes an acute infectious viral disease with high mortality in young salmonid fish. Serotypes Sp, Ab, WB of the IPNV were cultivated in BF-2 cells and purified by linear sucrose density gradient centrifugation. Hyperimmune sera against purified IPNV serotypes were collected from immunized guinea pigs. Coagglutination test conjugates were prepared by using sensitized S. aureus and hyperimmune sera. Cell culture derived salmonid pathogens such as infectious hematopoietic necrosis virus (IHNV), viral haemorrhagic septicaemia virus (VHSV) and epizootic hematopoietic necrosis virus (EHNV) were used to determine the specificity of the test as control. Upward comparison of the preferability for the rapid diagnosis was also carried out with ELISA and RT-PCR. The validation studies of newly developed coagglutination test were carried out in accordance with the Manual of Diagnostic Tests for Aquatic Animals. Consequently, determined detection limit of the test was approximately 105.25 TCID50/mL for the Sp and Ab serotypes and 107.75 TCID50/mL for the WB in laboratory conditions. The results indicated that newly developed coagglutination test was compatible with ELISA and RT-PCR in positive cell culture supernatants. It was concluded that this test would be an economic, rapid and reliable method for the diagnosis of IPN virus in cell culture.