**3.2 Filamentous bacterial disease**

The disease was characterized by fouling of gills, setae, appendages and body surface. Molting is impaired and the larval shrimp may die due to stress and hypoxia, which is caused by filamentous bacteria such as *Leucothrix mucor*, which is diagnosed microscopically. This can be prevented by maintaining good water quality with optimal physical – chemical conditions controlled by 0.25–1 ppm copper sulphate bath treatment for 4–6 hours [9].
