There currently is no available mechanical method for counting emerging coldwater species fish fry under 15 grams. Often the fry are counted in the eyed egg state approximately three weeks after they are collected. Incubation periods are dependent on water temperatures and species and vary from four to six weeks. As the blanks (unfertilized eggs) and weaker eggs die, the mortalities are counted and subtracted from the original number. The resulting difference is the calculated number of fry. Sampling techniques are also common, such as counting the number of fry in a given weight, such as a pound or ounce, then multiplying this number by the number of pounds. This results in a reasonably accurate count but is very labor intensive. Cannibalism, holes in screens, predators and reporting inconsistencies combine to produce inaccurate fry counts. An accurate, easy to operate, electro-mechanical device would be an asset to hatcheries that need precise counts of fish fry to manage their operations.Applications:This project will determine whether a practicable, simple technique can be produced to provide an accurate count of coldwater species fish fry at stages of development under 15 grams. The technique would, by necessity, be gentle and manifest minimal trauma to the developing fry. Application of this technology would involve the development of an electro-mechanical means of counting each fry individually. This capability would substantially enhance hatchery production mal agement.Title: Development Of A Recombinant Ipnv Vaccine For Protection Of Salmonid FishFY92 USDA SBIR Phase_IMarigenetics, Inc.Corvallis, ORAbstract:Infectious pancreatic necrosis virus (IPNV) causes a highly contagious disease in young salmonid fish which can result in mortalities of greater than 90%. This disease, which is currently untreatable, is of considerable economic significance to the aquaculture industry. Immunization may provide the protection needed to prevent disease outbreaks and a recombinant IPNV subunit vaccine has been developed. The vaccine consists of a Iysate of Escherichia coli containing a plasmid encoding a cDNA copy of the entire genomic segment A of IPNV. Viral VP2, NS and VP3 proteins are expressed and protection has been induced in fish in a preliminary small-scale trial. However, the protein responsible for protection is still unknown. The major capsid protein, VP2, induces neutralizing antibodies and contains common and unique epitopes. VP3 induces binding antibodies. To determine the role of each protein in inducing protection, additional plasmids will be constructed and evaluated for vaccine efficacy. These plasmids will contain the 5' end of VP2 gene, the entire VP2 gene alone, or the VP3 gene alone. Subsequently, experiments will be conducted to determine which of the recombinant subunit vaccines is the most effective in protecting salmonid fish against several IPNV isolates and serotypes.Applications:It is expected that one of the recombinant subunit vaccines will induce significant protection against IPNV in young salmonid fish. The most efficacious vaccine will be developed commercially for use in public and private salmonid aquaculture facilities in the U.S. and worldwide. The success of the IPNV subunit vaccine will confirm that the molecular approach to vaccine development is a viable technology for application to other viral diseases of importance to the aquaculture industry.
