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In recent years, jaundice disease in farmed hybrid catfish in Thailand has caused high levels of mortalities. Affected fish are lethargic and anorexic and show yellow pigmentation of the skin and gills. Internally, the spleen, kidney and gall bladder are enlarged, and the spleen, kidney, liver and body fat are a pale yellow colour. Most fish contain a yellow ascitic fluid in their abdomen. Histological examination of tissues from diseased fish revealed heavy deposits of haemosiderin and ceroid in the spleen, kidney and liver. Haematological measurements showed that haematocrit values, RBC count, haemoglobin concentration. MCH and MCHC were significantly decreased in affected fish while MCV, total bilirubin and direct reacting bilirubin were significantly increased. The results indicate that the fish are suffering from a haemolytic anaemia associated with lipoid liver degeneration. The disease is thought to be due to the feeding of rancid chicken viscera. [ABSTRACT FROM AUTHOR]

Snakeheads, Channa striatus (Bloch), were inoculated with a spore suspension of the specific pathogenic Aphanomyces, isolated from fish affected by epizootic ulcerative syndrome (EUS), in South East Asia. Fish were held at three different temperatures: 19, 26 and 31 °C. Histological changes induced by the infection are described. In the early stages of the disease, degenerative changes were observed in all samples, but inflammatory infiltrate was much more marked in fish kept at 26 and 31°C. By 8 days post-injection, extensive mycotic granulomatosis was observed in the samples kept at 26 and 31°C. The fish kept at 19°C developed a severe invasive myonecrosis with limited macrophage response. From 14 to 28 days post-injection, healing became well established at 26 and 31 °C and surviving fish kept at these temperatures recovered completely by 28 days. The lesion was still progressing at 21 days post-injection in fish kept at 19°C, and all such fish succumbed by this time. Thus, mortalities in the fish kept at 19 °C were considerably higher than in the groups of fish kept at 26 and 31 °C. The findings help to explain why mortalities from EUS occur when water temperatures are low. [ABSTRACT FROM AUTHOR]