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Showing posts from September 1, 2011

Shrimp Disease: Disease Yellowhead

Shrimp Disease: Disease Yellowhead Cause: Yellow Head Virus (YHD), corona-like RNA virus (genus Okavirus, family Ronaviridae and the order Nidovirales) Bio - Ecology of Pathogens: • Krustase sensitive to infection with this virus include: Penaeus monodon, P. merguensis, P. semisulcatus, Metapenaeus ensis, Litopenaeus vannamei, etc.. • Shrimp black tiger shrimp is a very sensitive species, in acute cases can result in the death of up to 100% within 3.5 days since the first clinical symptoms appear. • Transmission occurs horizontally through the water shrimp or cannibalism to feed a sick or infected. • Post larvae (PL) shrimp aged <15 days relative resisters against infection with this virus compared with 20-25 days old PL or juveniles. • The molecular (DNA sequencing) from products of reverse-transcription polymerase chain reaction (RT-PCR) of yellow head virus have similarities to the gill-associated virus (Gav), although different species or strains. Clinical Sympto