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Luminous disease is known as the most popularly dangerous disease in the hatcheries of mud crab (Scylla serrata) in northern provinces. Without any treatment, the mortality caused by this disease may reach 50 - 100% after 2 - 3 days infected. In this study, Vibrio harveyi has been identified as the main pathogen which causes the disease in larvae and juvenile of mud crab by using method for bacteria identification (bio-chemical reaction and comparision of the gene 16S rDNA) as well as artificial disease infection. In addition, we have developed successful prevention and treatment for this disease as follows: potasium permanganate, chlorine, formaline used for treatment of water, crab spawners, living food (artemia), utensils and equipment, after that one of the three different kinds of antibiotics can be used: Neomycine, Erythromycine or Doxycyclin. For prevention, the dose of 2 ppm/day can be applied for 3 consecutive beginning days of each development stage (Zoea, Megalope and juvenile), and 3 ppm/day can be applied for 3 consecutive days for disease treatment.

This is the first study to examine the effect of three different cultivation methods (bottom-tray culture, suspended-tray culture, and beach/bottom culture) on the growth and survival rates of the snout otter clam, Lutraria philippinarum, after 12 months of grow-out cultivation from seed to commercial size. Analyses included weight, survival, shell size, and total fat. Although the results showed limited differences in growth among cultivation methods, survival rates were significantly different among three different culture methods. The bottom-tray cultivation method had the highest survival rate (76.5%), compared with suspended-tray cultivation (31.6%) and beach/bottom cultivation (52.5%). This demonstrates that the most suitable method for commercial snout otter clam farming is cultivation trays placed on the bottom of the substrate. Improving commercial farming of the species will support the development and expansion of aquaculture in Vietnam and elsewhere, while reducing the harvest pressure on wild populations.