To obtain insights into cobia cage culture in the Mekong Delta, Vietnam,

90 farmers were interviewed for technical information and fish health

management practice. Results showed that the quality of artificial spawning

fingerlings was unstable and become a major constraint for the development

of cobia aquaculture. Most of the farmers (80%) reported having disease

symptoms during cobia cultivation. The clinical signs included abnormal

eyes (57.8%), parasite infection (45.6%), and ulcerated skin or external

abnormality (32.2% of farmers reported). Farmers (48%) used five single

antibiotics and one mixture of antibiotics to control the clinical sign by

mixing with fresh water. The most common antibiotics were oxytetracycline

(23.3% of farmers used), tetracycline (16.7%), and ampicillin (16.7%). Most

of the farmers used chemicals following their own experience, 70% of

farmers reported. None of the farmers reported being trained in the safety of

handling chemicals and knowledge of chemical use. In general, there is an

urgent need to train farmers on chemical use, disease diagnosis, and

approach to fish health management services