Abstract
Streptococcus phocae,a beta-hemolytic streptococcal species, has been reported in multiple marine mammal species globally as a commensal, opportunist, and primary pathogen.1-7 Clinical manifestations include upper respiratory disease, pneumonia, abscessation, abortions, septicemia, and death.1,4,5,6,8, Streptococcus equi subspecies equi, also a beta-hemolytic streptococcal species,is the equine pathogen known as 'strangles' causing swelling and abscess formation in the cranial lymph nodes.8 Here, we report on three bottlenose dolphins, during 2009–2010, that developed clinical signs from Streptococcus phocae similar to those seen in horses with strangles. A 4 year old female dolphin presented with a severe inflammatory hemogram, neutrophilic leukocytosis, and unilateral cervical lymphadenopathy. Ultrasound-guided, fine needle aspiration (FNA) confirmed the presence of S. phocae via culture and PCR of the suppurative exudate. Histopathology confirmed lymphadenitis. The animal responded to antimicrobial therapy combined with repeated FNA procedures. The second and third dolphins, a 24 year old female and a 5 year old male, presented one year later with similar signs. The presence of S. phocae was again confirmed via PCR and culture. Intralesional ampicillin therapy was also instituted in the latter animals. Clinical resolution, defined as normal blood parameters and resolution of lymphadenopathy, was achieved in all 3 animals. Exposure to this organism is suspected to derive from wild pinnipeds in close proximity to Navy animals. This suspicion, however, has not been validated, and is under investigation. To our knowledge, this is the first report of S. phocae known to cause a strangles-like syndrome in bottlenose dolphins.
Acknowledgements
The authors wish to thank the U.S. Navy Marine Mammal Program Records Office and training staff for all their help and support.
References
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