1Northwest ZooPath, Monroe, WA, USA; 2Oklahoma City Zoo, Oklahoma City, OK, USA; 3Safari Animal Care Center, League City, TX, USA; 4Washington Animal Disease Diagnostic Laboratory, Pullman, WA, USA; 5California Animal Health and Food Safety Laboratory, School of Veterinary Medicine, University of California, Davis, CA, USA
Abstract
This report describes Coxiella infection in two Swainson’s Blue Mountain Rainbow lorikeets (Trichoglossus haematodus moluccanus) and one bronze-winged pionus parrot (Pionus chalcopterus). The lorikeets were housed in an indoor/outdoor multi-species exhibit at the Oklahoma City Zoo and were in the same age cohort. Ages ranged from 6–8 months at the onset of clinical signs, which included fluffed appearance, lethargy, weakness, and inappetence. The birds did not respond to various combinations of antibiotics, fluids, or steroids. The birds were euthanatized following development of progressive neurologic signs that included head pressing, ataxia, hyperesthesia, intention tremors, hemiparesis, and seizure-like activity. The pionus was a 1-year-old female from a large aviary and had a 2-week history of illness prior to death.
Necropsy of the lorikeets revealed thin body condition (2), hepatomegaly (2), and splenomegaly (1). Necropsy of the pionus revealed hemorrhage in the lungs and air sacs. Histologic examination revealed disseminated microgranulomatosis in liver and spleen (3), nonsuppurative encephalitis with microgranulomas (3), and mild lymphohistiocytic enteritis (2). Iron sequestration was occasionally seen in the splenic and hepatic microgranulomas. Gimenez and PAS stains identified single to multiple approximately 1-micron intracytoplasmic inclusions within macrophages of the brain in all birds. Fite’s acid fast, Warthin Starry, Brown and Brenn, and Giemsa stains did not identify organisms in the lesions. Electron microscopic examination of brain from one bird identified spherical to rod shaped prokaryotic organisms within lysosomes. These organisms were approximately 400 nm in diameter and had a trilaminar cell wall similar to that of gram-negative bacteria. Immunohistochemistry for Coxiella burnetii was negative in one bird. The PCR sequence had 97% homology with Coxiella burnetii when compared with the sequence in GenBank. This likely represents a previously unknown species of Coxiella. The Coxiella genus has recently been reclassified within the Legionellaceae.
Literature Cited
1. Grattard, F., C. Ginevra, S. Riffard, A. Ros, S. Jarraud, J. Etienne, and B. Pozzetto. 2006. Analysis of the genetic diversity of Legionella by sequencing the 23S-5S ribosomal intergenic spacer region: from phylogeny to direct identification of isolates at the species level from clinical specimens. Microbes Infect. 8:73–83.
2. Liu, H.C., Q.Z. Yin, M.J. Ye, C.W. Zhang, J. Liao, and Q.X. Peng. 1989. A serological survey of Legionnaires’ disease in domestic fowls and animals in Chengdu area. Hua Xi Yi Ke Da Xue Xue Bao. 20:441–444.
3. Reeves, W.K., D.G. Streicker, A.D. Loftis, and G.A. Dasch. 2006. Borrelia, Coxiella, and Rickettsia in Carios capensis (Acari: Argasidae) from a brown pelican (Pelecanus occidentalis) rookery in South Carolina, USA. J Vector Ecol. 31:386–389.
4. Roux, V. and D. Raoult. 1995. Phylogenetic analysis of the genus Rickettsia by 16S rDNA sequencing. Res Microbiol. 146:385–396.
5. Stein, A. and D. Raoult. 1999. Pigeon pneumonia in provence: a bird-borne Q fever outbreak. Clin Infect Dis. 29:617–620.
6. Zuber, M., T.A. Hoover, and D.L. Court. 1995. Cloning, sequencing, and expression of the dnaJ gene of Coxiella burnetii. Gene. 152:99–102.