Diagnosis and Treatment of Gordonia Species Infection in a Peach-Faced Lovebird (Agapornis roseicollis).

Respiratory distress is a common presentation for avian species. A 9-week-old peach-faced lovebird (Agapornis roseicollis) was presented with a 2-week history of progressive dyspnea. Computed tomographic (CT) images were suggestive of splenomegaly and bilateral granulomatous pulmonary disease. Polymerase chain reaction testing of samples from the choana, cloaca, and distal tracheal/syringeal area were positive for Mycobacterium species hsp65. A comparison search of the 400 base pair sequence in the NCBI/BLAST/blastn database revealed a best match of 93% similarity to Gordonia species and 91% similarity to Gordonia bronchialis. Gordonia is a genus in the phylum Actinomycetota, the same lineage that includes Mycobacterium species. Gordonia species can be mistaken for Mycobacterium species unless more definitive diagnostic testing is pursued. Infection caused by Gordonia species is rare in humans. Reports commonly cite infection of immunocompromised patients, and to our knowledge, no reports of treatment have been published in the veterinary literature. After the test results were obtained, the patient was treated with azithromycin and pradofloxacin for 3 months. The lovebird was presented for reexamination when the antibiotic treatment was complete. When reexamined, and a second series of CT images evaluated, it was determined that the treatment achieved clinical resolution of signs and lesions.

Liposarcoma of Probable Medullary Bone Origin in a Lovebird (Agapornis roseicollis).

A 15-year-old female peach-faced lovebird (Agapornis roseicollis) was presented to the hospital for a possible left wing injury and an inability to fly after falling in its cage. On physical examination the left elbow was swollen and painful. Radiographic images revealed left wing soft tissue swelling surrounding the elbow and lysis of the distal humerus with extensive cortical thinning. Subsequent high-definition volumetric-imaging 3-dimensional computed tomography (HDVI 3D CT) revealed a pathological fracture, cortical lysis, periosteal reaction, and abnormal intraosseous soft tissue of the left humerus with associated soft tissue swelling, suggestive of neoplasia. No evidence of metastatic disease was identified. Surgical amputation of the left wing was elected. A liposarcoma and pathologic fracture of the humerus were diagnosed histologically and by oil red O staining for lipids in the neoplastic cells. The morphologic features of the tumor suggested that it developed within the adipocyte component of the medullary bone. The incision at the amputation site healed without complication. A follow-up HDVI 3D CT performed 4 months postsurgery showed no evidence of metastatic disease. To the authors' knowledge, this is the first report of a primary liposarcoma of medullary bone origin in an avian species.

MYCOTIC PNEUMONIA AND ENCEPHALITIS IN SOUTHERN PUDU (PUDU PUDA).

This case series describes six confirmed cases of mycotic encephalitis and/or mycotic pneumonia in southern pudu (Pudu puda). One case involved a 10.5-yr-old intact female that presented with an inability to stand, eventually progressing to grand mal seizures. Magnetic resonance imaging showed a lesion within the cerebellar vermis with edema causing cerebellar herniation. The animal was euthanized based on a grave prognosis. Gross and histologic examination revealed primary central nervous system phaeohyphomycosis. Curvularia spicifera was sequenced from the cerebellar tissue. This is the first time this fungus has been reported as a primary central nervous system infection in an artiodactyl species. The remaining five cases occurred in neonates between 17 and 67 days old. Clinical signs varied widely, including facial swelling, weakness, posterior paresis, and sudden death. Antifungal therapy was initiated in three neonatal animals but was unsuccessful in each case. All neonates had active mycotic pneumonia caused by Aspergillus fumigatus or Mucor spp. at time of death; four of these animals also had disseminated disease that caused mycotic encephalitis. This case series indicates that fungal disease should be included in the differential diagnosis list of any pudu presenting for neurologic or respiratory clinical signs.

In vivo measurement of lung volume in ringed seals: insights from biomedical imaging.

Marine mammals rely on oxygen stored in blood, muscle and lungs to support breath-hold diving and foraging at sea. Here, we used biomedical imaging to examine lung oxygen stores and other key respiratory parameters in living ringed seals (Pusa hispida). Three-dimensional models created from computed tomography (CT) images were used to quantify total lung capacity (TLC), respiratory dead space, minimum air volume and total body volume to improve assessment of lung oxygen storage capacity, scaling relationships and buoyant force estimates. The results suggest that lung oxygen stores determined in vivo are smaller than those derived from postmortem measurements. We also demonstrate that, whereas established allometric relationships hold well for most pinnipeds, these relationships consistently overestimate TLC for the smallest phocid seal. Finally, measures of total body volume reveal differences in body density and net vertical forces in the water column that influence costs associated with diving and foraging in free-ranging seals.

Septic Arthritis and Osteomyelitis Caused by Chryseobacterium indologenes in a Mute Swan (Cygnus olor) and a Ring-Billed Gull (Larus delawarensis).

A 20-year-old female mute swan (Cygnus olor) originally in a flock of free-living swans on a Long Island, New York, lake, was presented for facial swelling and decreased appetite. An adult male ring-billed gull (Larus delawarensis) was also presented to the same wildlife rescue center for bilateral lameness of 1-week duration. Once referred for veterinary evaluation and care, both species were diagnosed with septic arthritis and osteomyelitis caused by Chryseobacterium indologenes and treated with orbifloxacin until complete recovery. Chryseobacterium indologenes is infrequently diagnosed as an opportunistic pathogen in human medicine, and less so in veterinary medicine. In human patients, this bacterium is the cause of various infections, including meningitis, pneumonia, and implant failure. However, in veterinary medicine its pathogenicity has only been reported in fish, and sporadically mentioned as a culture result in tree frogs and turtles, where it was generally considered insignificant. In this report a clinical presentation, diagnosis, treatment, and outcome of osteomyelitis and septic arthritis caused by C indologenes is described in 1 anseriforme and in 1 charadriiforme species.

Hyperbaric tracheobronchial compression in cetaceans and pinnipeds.

Assessment of the compressibility of marine mammal airways at depth is crucial to understanding vital physiological processes such as gas exchange during diving. Very few studies have directly assessed changes in cetacean and pinniped tracheobronchial shape, and none have quantified changes in volume with increasing pressure. A harbor seal, gray seal, harp seal, harbor porpoise and common dolphin were imaged promptly post mortem via computed tomography in a radiolucent hyperbaric chamber. Volume reconstructions were performed of segments of the trachea and bronchi of the pinnipeds and bronchi of the cetaceans for each pressure treatment. All specimens examined demonstrated significant decreases in airway volume with increasing pressure, with those of the harbor seal and common dolphin nearing complete collapse at the highest pressures. The common dolphin bronchi demonstrated distinctly different compression dynamics between 50% and 100% lung inflation treatments, indicating the importance of air in maintaining patent airways, and collapse occurred caudally to cranially in the 50% treatment. Dynamics of the harbor seal and gray seal airways indicated that the trachea was less compliant than the bronchi. These findings indicate potential species-specific variability in airway compliance, and cessation of gas exchange may occur at greater depths than those predicted in models assuming rigid airways. This may potentially increase the likelihood of decompression sickness in these animals during diving.

In Vivo Measurements of Lung Volumes in Ringed Seals: Insights from Biomedical Imaging.

Marine mammals rely on oxygen stored in blood, muscle, and lungs to support breath-hold diving and foraging at sea. Here, we used biomedical imaging to examine lung oxygen stores and other key respiratory parameters in living ringed seals (Pusa hispida). Three-dimensional models created from computed tomography (CT) images were used to quantify total lung capacity (TLC), respiratory dead space, minimum air volume, and total body volume to improve assessments of lung oxygen storage capacity, scaling relationships, and buoyant force estimates. Results suggest that lung oxygen stores determined in vivo are smaller than those derived from postmortem measurements. We also demonstrate that-while established allometric relationships hold well for most pinnipeds-these relationships consistently overestimate TLC for the smallest phocid seal. Finally, measures of total body volume reveal differences in body density and net vertical forces in the water column that influence costs associated with diving and foraging in free-ranging seals.