W. George Miller, DVM, PhD
The death of a Tursiops truncates fetus is attributed to Brucella due to the pathologic observations and specific identification of a Brucella spp. in the placenta with ImmunoCyt histochemistry technique. The fetus was aborted 3 months premature and showed a marked degree of autolysis upon delivery. Microbiology results combined with specific Polymerase Chain Reaction results suggest this is a new Brucella species, for which the name Brucella delphini is suggested. Current serological diagnostic tests reliable for known Brucella spp are unreliable in detecting dolphin brucellosis. The National Animal Disease Center in Ames, Iowa is currently working to develop a dolphin brucellosis test.
Our findings, together with the results from Ross et al., (1994), suggest that dolphin brucellosis is a naturally- occurring disease that could adversely impact reproduction in cetacean species. A. P. MacMillan (pers. comm.) describes Brucella lesions from stranded dolphins on the Scottish coast as "spreading abscesses between the blubber and the facie overlying the back" and he stated Ross has isolated Brucella (in very low numbers) from 10% of stranded dolphins on the Scottish coast. The significance of cetacean brucellosis and health implications for potential zoonotic infection is unknown.