Jacqueline E. Jencek1, DVM; Freeland H. Dunker1, DVM; Thomas N. Tully, Jr.2, DVM, DABVP (Avian); Michael M. Garner3, DVM, DACVP
This report describes an outbreak of avian chlamydiosis in an outdoor colony of Magellanic penguins (Spheniscus magellanicus) at the San Francisco Zoo in 2005. Affected birds presented with depressed appetite, lethargy, and mint green urates. Findings included elevated white blood cell counts (25,000–60,000/µl), heterophilia and lymphopenia with toxic cellular changes, and increased total plasma protein. Clinical signs and pathology associated with chlamydiosis infection and/or the associated treatments included prolonged anorexia, seizures, keratoconjunctivitis, dermatitis, gout, sepsis, and cardiac insufficiency.
Chlamydophila psittaci infection was confirmed as the cause of death by histopathology and immunohistochemistry in the first three cases. Subsequently the entire colony was treated prophylactically with doxycycline. Oral doxycycline hyclate (Axiom Pharmaceutical Corp., Rockford, IL, USA) at a dosage of 17–33 mg/kg PO SID and/or injectable doxycycline (Vibramycin SF IV, 20 mg/ml, Merknaam van Pfizer Inc., New York, NY, USA) at a dosage of 50–75 mg/kg IM every 7 days was administered for a 30-day treatment.
Avian chlamydiosis is an infectious disease with zoonotic potential1-4 and Chlamydophila psittaci is a reportable disease in the state of California. Public Health officials were notified, and appropriate quarantine protocols were instituted.
Following histopathologic confirmation of avian chlamydiosis, an attempt was made to establish antemortem diagnostic screening protocols for C. psittaci in Magellanic penguins. Polymerase chain reaction (PCR; DNA) probes for C. psittaci from feces and choanal/cloacal swabs were the most useful in the diagnosis of infected birds and helped to determine shedding status. Results from swabs were superior to direct complement fixation, elementary body agglutination, and PCR blood testing.
The authors gratefully acknowledge the penguin keepers and hospital staff for their hard work and dedication. The San Francisco Zoo wishes to acknowledge Lynn Dustin, VMD, for her truly generous contribution of numerous vials of injectable doxycycline.
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2. Flammer, K. 2003. Chlamydiosis. In: Fowler M. E., and R.E. Miller, eds. Zoo and Wild Animal Medicine. 5th ed. Saunders Co., St. Louis, MO. Pp. 718–723.
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