Abstract:The skin ulcer syndrome is a serious disease causing massive mortality and economic losses in cultured sea cucumber Apostichopus japonicus. Vibrio splendidus was identified as one of the most severely pathogeneses of this disease. In the present study, a DIG-labeled V. splendidus DNA probe based on the sequence of the 16S~ 23S rDNA intragenic spacers was synthesized and was used to establish in situ hybridization for detecting the bacterium in A. japonicus. V. splendidus-positive cells were observed in connective tissue, muscle tissue, epithelium of intestine and water-vacular tissues in artificial infected A. japonicus, while no cross-reaction was observed in tissues of healthy sea cucumber. The positive signals were clear in infected tissues, which could reveal the location and degree of the infection. Therefore, this established approach is useful to indicate the infection route and the pathogenesis of V. splendidus infection, which will provide basic data for disease control and animal health management.
