Histopathology of Yearling Sockeye Salmon (Oncorhynchus nerka) Infected with Infectious Hematopoietic Necrosis (IHN)
Infectious hematopoietic necrosis (IHN) is generally believed to be a virus disease of very young salmonids. In recent years there have been increasing numbers of unpublished reports that this disease has been occurring uncharacteristically in fish as old as 7-14 months. Sockeye salmon (Oncorhynchus nerka) of this age the histological changes were not severe. Intestinal tract granular cells thought to be pathognomic in young fish were conspicuously absent. Kidney imprints showed necrobiotic bodies however, and subtle changes were observed in the spleen and kidney hematopoietic tissue.
We combine in situ electrochemical second- harmonic generation (SHG) with voltammetry measurements using the hanging meniscus configuration. This setup is used to investigate the interface between a Ag (111) electrode and an alkaline electrolyte. The study offers a new in situ insight into the electrochemical processes at the Ag (111) electrode dur- ing OH adsorption and subsequent oxidation. The behavior of SHG isotropic and anisotropic contributions as a function of po- tential is discussed and related to the interfacial electric field. Comparison of the results with previous investigations of the Ag underpotential oxidation in alkaline solutions shows that submonolayer oxidation is followed by bulk oxidation.