Bacterial pathogens and health problems of Acipenser gueldenstaedtii and Acipenser baerii sturgeons reared in the eastern Black Sea region of Turkey

Farming sturgeons is an economically important practice in a number of Asian and European countries. However, since it is not widely implementedin Turkey, fertilized eggs necessary for research and industrial activities are imported from Germany. Due to the interest of several fish farms in culturing sturgeon in Turkey and the lack of relevant data, this study investigated bacteria related health problems of two different sturgeon species, the diamond sturgeon (Acipenser gueldenstaedtii) and the Siberian sturgeon (Acipenser baerii). The fungal, parasitic and bacterial pathogens found in these fish were investigated until the fish reached about 3 kg of weight (3+ years). A number of bacterial disease pathogens (Acinetobacter radioresistens, some Aeromonas and Pseudomonas species and Bacillus mycoides) and parasite Trichodina sp. and fungus Saprolegnia sp. were identified in the fish. Both phenotypic and molecular characterizations of the isolated bacteria were performed. Furthermore, swim bladder and spinal problems, cannibalism, tumor growth and mechanical injuries on the external surface of the fish were observed during the study period.