Brucella-induced abortions and infection in bottlenose dolphins (Tursiops truncatus)

Two bottlenose dolphins (Tursiops truncatus) aborted fetuses that died as a result of Brucella infection. Brucella placentitis occurred in both cases. Infected placenta and vaginal/uterine fluids may transmit Brucella species to other cetaceans. In a third case, an identical organism was cultured fr om lung necropsy tissue of an adult female T. truncatus. Microbiology, spec ific polymerase chain reaction, and pulsed-field gel electrophoresis result s supported the designation of an additional genomic group(s), Brucella del phini, for isolates adapted to T. truncatus. Current serologic diagnostic t ests reliable for known Brucella species are unreliable in detecting dolphi n brucellosis. Our findings, together with previous reports, suggest that d olphin brucellosis is a naturally occurring disease that can adversely impa ct reproduction in cetaceans. The zoonotic significance of cetncean brucell osis is unknown, although the disease has not been reported in people who h ave frequent contact with dolphins. Further studies. on the zoonotic aspect s, distribution, prevalence, virulence, and impact of this disease in cetac eans and other marine mammal species are needed.