Flexibatteriosi da Tenacibaculum maritimum sierotipo O3 in pesce capone (Chelidonichthys lucerna L.) d’allevamento: prima segnalazione in Italia. First report of Tenacibaculum maritimum serotype O3 infecton in cultured tub gurnard (Chelidonichthys lucerna) in Italy.

The present study describes the first isolation of Tenacibaculum maritimum from tub gurnard (Chelidonichthys lucernus L.), cultured in Italy. After 3 days shipment from one fish farm to our laboratory facilities, a group of 20 tub gurnard showed eroded mouth, rotten fins and severe skin ulcerative lesions. Mortality reached 90% of the population in 9 days. Traditional bacteriological and PCR analysis allowed the identification of the causative agent as T. maritimum. Serological characterization of the isolate demonstrated that it belongs to serotype O3. Histopathological examination showed severe skin necrosis, dermis congestion associated with eterophilic and macrophagic infiltration. Immunohistochemical analysis, using specific polyclonal antiserum against T. maritimum serotype O3, allowed the visualization of numerous positively stained macrophagic cells. The high mortality observed during the outbreak leads to consider the T. maritimum as a potential risk for the culture of tub gurnard.