Effects of Chlorella-feeding on larval milkfish, Chanos chanos, as evidenced by histological monitoring

An infectious pancreatic necrosis virus, IPNV, serologically related to the Ab serotype, has been isolated during an epizootic in 7-month-old turbot. The outbreak occurred after asymptomatic carriers were transferred from the farm where they were kept at 11°C to experimental facilities supplied with sea water at 18°C. Diseased fish were lethargic and displayed muscular haemorrhages and a severe necrosis of the haemotopoietic tissue of the kidney. Virus yields higher than 2×1010 pfu g−1 were recovered from the organs of moribund turbot. The losses were significantly higher at 18° than 11.5°C. Transmission of the disease could be experimentally demonstrated at 18°C by injecting 3-month-old turbot intraperitoneally with 6×108 pfu of virus. The mortality reached 56% in the injected group and no fish died in the control.