Abstract

On April 1, 2006, a juvenile female Atlantic bottlenose dolphin (TL 205 cm) was found stranded on Longboat Key, Florida. The dolphin was transported a short distance to the Dolphin and Whale Hospital for assessment and possible rehabilitation. On presentation the dolphin had numerous rake marks from dolphin interactions and multiple healed skin lesions. In addition, there was a large swelling near the left shoulder. The dolphin was given oral fluids and injections of Vitamin E/selenium and enrofloxacin. Blood tests indicated a normal white count, an elevated erythrocyte sedimentation rate, and low alkaline phosphatase. The dolphin was placed in the water and seemed very eager to swim. After a short acclimation period of being supported by personnel, dolphin was allowed to swim on its own. It swam very rapidly as though frightened, which is not an unusual occurrence with wild animals on first being brought into captivity, but this type of swimming behavior usually subsides within an hour or so. With this particular dolphin, it did not subside and the animal swam rapidly until it sank to the bottom and had to be rescued. Shortly thereafter, it fought to swim again, and so was allowed to do so, but once more swam very rapidly until it again sank to the bottom. At this point the animal was very shocky and died moments later. Necropsy revealed an empty gastrointestinal tract, thin blubber layer, no evidence of injury to left shoulder area, and Nasitrema sp. infestation with inflammation in the nasal sinus. Histopathology revealed a non-suppurative meningitis, verminous pneumonia (Halocercus sp.), and verminous gastritis (Braunina sp.). Dolphin was negative on virus serum neutralization for DMV, PMV, and PDV but was positive on iELISA for brucellosis. Two independent attempts to culture the brain produced Brucella sp. growth. Identification of the organism was confirmed via PCR. Given the zoonotic potential of this organism, care must be exercised when handling cetaceans with any evidence of neurologic symptoms.