Pathognomonic of Viral Nervous Necrotic (VNN) virulence on larvae of Humpback grouper (Cromileptes altivelis)

The constraints of the cultivation of Humpback grouper was attacked by infectious agents like VNN. VNN had attacked most of grouper cultured with mortality till 100%. An overview of virus infection both in cells and tissues can describe a symptom changes and functions of cells and tissues, therefore the purpose of this research was to look VNN attack on larvae of groupers that is focused on the status of the infected fish tissue in larvae stage which describe pathognomonic of VNN virulence qualitatively. The research method is qualitative experimental using histopathology technical with target research using tissue gills, liver, intestines, kidneys and intestines observed by optical microscope and Scanning Electron Microscope (SEM). Histopathology observation of using inverted microscope show the effect of VNN infection on grouper tissue structural change, such as hypertrophy, hyperplasia, oedema, vakuolasi, cloudy swelling, atrophy, vakuolasi, necrosis, occlusion bodies, inclusion bodies, proliferation goblet and rupture of the epithelial tissue. VNN infection on larval stadia able to lead the death of fish which characterized by structural changes tissues of them.