Infection progress of Viral Nervous Necrosis (VNN) in Trichinotus blochii cultured in deep sea cages, Langkawi

Objective: A batch of golden pomfret samples were sent to the National Fish Health Research Centre (NaFisH) for routine diagnosis after showing disease symptoms. This imported Golden pomfret was reported to have more than 60% mortality with spiral swimming pattern and dark body colouration during conditioning at the hatchery. Method & Materials: Physical examination and necropsy was done and samples were taken for parasites, bacterial and viral detection using standard method. This batch of fish was then monitored for their health status after 4 and 7 month reared in cages. Parasites and bacterial were not detected in the samples but RT-PCR gave positive VNN infection. The RT-PCR result was confirmed by sequencing method. However, CPE was negative in both E-11 and SB cell cultures. Results & Conclusion: The results showed that continued culturing of VNN infected fish might cause future problem which directly reduced the profit of the farmer. Early viral detection especially VNN in marine fish should be practiced all the time to ensure that the fish will be free from this disease, thus increase the survival rate during growing stages. As a conclusion, early detection and good management practices are critical in eliminating this disease in cultured system.

کلیدواژه ها:

diagnosis ، VNN ، golden pomfret ، disease progress