Comparison of In-Clinic Diagnostic Testing Methods for Macrorhabdus ornithogaster.

Macrorhabdus ornithogaster is an ascomycete yeast often found at the isthmus of the ventriculus and proventriculus of infected birds. Antemortem diagnosis has traditionally involved direct visualization of organisms on wet-mount or gram-stained fecal preparations, cloacal and crop swabs, or by both methods; however, different in-clinic diagnostic techniques have never been compared to establish an optimum test for the identification of M ornithogaster in an avian patient. We compared 5 microscopically evaluated diagnostic testing methods: fecal Gram's stain, direct fecal wet preparation, macro suspension technique, macro suspension with Gram's stain, and macro suspension stained with new methylene blue. Each technique was performed on 96 fecal samples collected during the treatment of M ornithogaster-infected budgerigars with water-soluble amphotericin B. The macro suspension technique produced statistically higher organism counts than the other 4 techniques and was always estimated to have the largest detection probability. We recommend that the macro suspension technique be implemented as the most efficacious diagnostic test for in-clinic assessment of avian patients possibly infected with M ornithogaster.

Multicentric Septic Osteomyelitis and Arthritis Caused by Staphylococcus aureus in a Gyrfalcon (Falco rusticolus).

An adult female gyrfalcon (Falco rusticolus) was presented with a right-wing droop and weight loss. Radiographic images revealed osteolysis and osseous proliferation of the right shoulder and the mobile vertebra between the notarium and synsacrum. The tentative diagnosis was vertebral osteomyelitis secondary to septic arthritis. The bird did not respond to antibiotic and anti-inflammatory therapy and represented 10 days later, with feathers soiled with feces, an impacted, dilated cloaca, and an inability to stand due to spastic paralysis of the hind legs. The bird's condition did not improve with 24 hours of supportive care and its quality of life was considered poor; therefore, the patient was euthanatized and submitted for postmortem examination. Multicentric septic osteomyelitis and arthritis were confirmed in the mobile vertebra between the notarium and synsacrum and the right shoulder. Despite 10 days of antibiotic therapy, Staphylococcus aureus was isolated from within the 2 locations in which septic osteomyelitis and arthritis were identified. This report describes the clinical features, diagnosis, and pathologic findings of septic osteomyelitis and arthritis caused by S aureus in a falcon.

A Novel Technique for Extracapsular Repair of the Intertarsal Joint in a Duck.

The intertarsal joint is a synovial roll-and-glide joint. Ligament damage and luxations of this joint are often the result of traumatic injury or growth deformities and result in significant functional impairment. A 9-month-old female Pekin duck ( Anas platyrhynchos domesticus) was examined because of progressive, nonweight-bearing lameness of the left leg. Moderate effusive swelling was present at the level of the left intertarsal joint, without radiographic evidence of bone involvement. The duck failed to respond to nonsteroidal anti-inflammatory medications and analgesia and was diagnosed with rupture of the medial collateral ligament. Extracapsular surgical correction using bone tunnels and circumferential nylon suture on the medial aspect of the intertarsal joint led to a complete clinical resolution with normal return to function 2 weeks after surgery. This report reviews the anatomy and function of the intertarsal joint in the duck and details a simple extracapsular repair technique useful in the correction of collateral ligament rupture in this joint of ducks.

Disease screening of three breeding populations of adult exhibition budgerigars (Melopsittacus undulatus) in New Zealand reveals a high prevalence of a novel polyomavirus and avian malaria infection.

Disease surveillance is vital to the management of New Zealand's endemic and threatened avian species. Three infectious agents that are potential threats to New Zealand's endemic birds include avian polyomavirus (APV), beak and feather disease virus (BFDV), and avian malaria. All three agents have been reported in New Zealand; however, possible reservoir populations have not been identified. In this communication, we report the first study of APV, BFDV, and avian malaria in introduced adult exhibition budgerigars (Melopsittacus undulatus) in New Zealand. Blood samples were collected from 90 living adult budgerigars from three breeding locations in the North Island of New Zealand. An overall APV prevalence of 22% was determined using a broad-spectrum nested PCR that amplified the major capsid protein VP1 gene of polyomavirus. Phylogenetic analysis of the VP1 gene revealed a unique isolate of APV, which had a sequence divergence of 32% to previously reported budgerigar fledgling disease strains and 33% to the recently reported New Zealand finch isolate. All of the budgerigars sampled were found to be PCR negative for BFDV, and an overall prevalence of 30% was detected by PCR for avian malaria. Sequencing revealed the presence of ubiquitous malarial strains and also the potentially destructive Plasmodium relictum strain. The results of this study suggest that both APV and avian malaria are present in New Zealand adult budgerigars, and our study highlights the need for further studies to determine whether these pathogens in captive bird populations may be a threat or spill over into New Zealand's endemic and threatened avifauna and whether prevention and control methods need to be implemented.