To further knowledge of the physiology of opioid receptors in birds, the structure and expression of the μ-, δ-, and κ-opioid receptor genes were studied in a peregrine falcon (Falco peregrinus), a snowy owl (Bubo scandiacus), and a blue-fronted Amazon parrot (Amazona aestiva). Tissue samples were obtained from birds that had been euthanatized for poor release prognosis or medical reasons. Samples were taken from the brain (telencephalon, thalamus, pituitary gland, cerebellum, pons, medulla oblongata, mesencephalon), the spinal cord and dorsal root ganglions, and plantar foot skin. Messenger RNA was recovered, and reverse transcription polymerase chain reaction (RT-PCR) was performed to generate complementary DNA (cDNA) sequences. Gene structures were documented by directly comparing cDNA sequences with recently published genomic sequences for the peregrine falcon and the blue-fronted Amazon parrot or by comparisons with genomic sequences of related species for the snowy owl. Structurally, the avian μ-opioid receptor messenger RNA (mRNA) species were complex, displaying differential splicing, alternative stop codons, and multiple polyadenylation signals. In comparison, the structure of the avian κ-receptor mRNA was relatively simple. In contrast to what is seen in humans, the avian δ-receptor mRNA structure was found to be complex, demonstrating novel 3-prime coding and noncoding exons not identified in mammals. The role of the δ-opioid receptor merits further investigation in avian species.

Ownership of backyard chickens (BYCs) is increasing in urban areas, and BYCs often have access to soil around the home. Exposure to lead-contaminated soil is a known health risk for people; however, the degree to which BYCs are exposed is unknown. We employed a cross-sectional convenience sample to assess blood lead levels (BLLs) in 57 BYCs from 30 flocks in a region with established environmental lead contamination. Over two-thirds (70.2%) had detectable levels of lead in their blood, which averaged 12.5 μg/dL (range: <3.3 μg/dL to ≥65.0 μg/dL). No chickens demonstrated clinical evidence of lead toxicosis. Almost all owners (96.2%) reported that their chickens had free access to soil, and almost three-quarters (69.2%) of the participants reported giving their chickens unrestricted access to the property. Our findings demonstrate that subclinical but elevated BLLs are common in BYCs that live in an environment where lead contamination may be present. Our data support the inclusion of blood lead testing in the routine veterinary care of BYCs, especially in areas where historic use of leaded paint and environmental lead contamination are reported.

Mycobacterium genavense is regarded as the primary cause of mycobacteriosis in passerine and psittacine birds kept in captivity. Mycobacterium genavense is a potential zoonotic pathogen; therefore, early antemortem detection in birds is needed. In humans, infections with M genavense are found predominantly in immunocompromised people. To investigate clinical signs and pathologic lesions and to determine the prevalence of coinfections in birds infected with M genavense, we reviewed records of 83 birds in which DNA from M genavense had been detected via real-time polymerase chain reaction. To evaluate clinical signs in birds presented as patients, results of standardized examinations of 60 birds and radiographic results from 37 birds were investigated. Necropsy results of 82 of the 83 birds were evaluated, including results of additional parasitologic, bacteriologic, and virologic examinations. Birds included in the study comprised 15 species in the orders Passeriformes, Psittaciformes, Coliiformes, Columbiformes, Coraciiformes, and Ciconiiformes. A wide range of clinical manifestations were documented, including neurologic disorders, ocular manifestations, and gastrointestinal signs. Of the 60 birds examined clinically, 15% showed no clinical signs. Coinfections with a wide range of pathogens were detected in 52% (43 of 83) of the tested birds. Coinfections included Macrorhabdus ornithogaster, circovirus, polyomavirus, avian bornavirus, adenovirus, Mycobacterium avium ssp. avium/silvaticum, Mycoplasma species, Salmonella species, Escherichia coli, Aspergillus species, and various parasites. The high number of coinfections may reflect an impaired immune status in the birds examined. These results also suggest a broad host range for M genavense, and the existence of various clinical signs that may be strongly associated with coinfections with other pathogens.

Tibiotarsal fractures are a common presentation in small bird species and anecdotally have been reported to carry a good prognosis with proper treatment, such as external coaptation. For this retrospective study, the medical records of 5 institutions were reviewed for tibiotarsal fractures diagnosed in companion birds weighing less than 200 g. A total of 86 cases met the inclusion criteria. Cockatiels (Nymphicus hollandicus) (24/86) and budgerigars (Melopsittacus undulatus) (19/86) were the most frequently represented species. Median body weight of the birds included was 72 g (range, 16–182 g). Mid-diaphyseal (46/86) and closed (73/86) fractures with intact, deep pain sensation in the affected limb (69/76) were most frequent. A tape splint alone (79/86) or a tape splint in addition to an intramedullary pin (7/86) were applied in all cases. Median time to fracture stabilization based on palpation was 19 days (range, 7–49 days). In most cases (61/86), the initial splint applied was maintained until fracture healing was complete. A successful outcome was documented in 92% (79/86) of birds. Fractures caused by a dog or cat attack, birds presenting without deep pain sensation in the affected limb, and cases where the splint was removed before 14 days after fixation were associated with a significantly increased risk of complications, resulting in an unsuccessful outcome. The findings of this study indicated that a tape splint is an appropriate means for treatment of tibiotarsal fractures in birds weighing less than 200 g.

An adult, male snowy owl (Bubo scandiacus) was found down and unable to fly in western New York State. Physical examination and radiographs revealed a subacute, open wound and fractured major and minor metacarpals of the right wing. A minimal type II external skeletal fixator (ESF) device was placed on the right major metacarpal bone and the open wound was allowed to granulate and close. After evidence of bone union, the ESF device was removed. The owl performed auto-physiotherapy throughout the process and was released with sustained flight 2 months postoperatively. It was recaptured 7 weeks later and underwent further rehabilitation to allow successful release 11 months after surgical stabilization. To our knowledge, this is the first case report describing use of a type II ESF device on the metacarpus of a bird.

A 1.5-year-old Polish hen was presented with a history of watery droppings and poor vent tone. Results of diagnostic tests revealed blood lead at levels considered to be toxic. Chelation therapy was started with calcium ethylenediaminetetraacetate. The hen was laying eggs before, during, and after chelation therapy. Eggs were tested for the presence of lead by combining yolk and albumen together. Before chelation therapy, the level of lead in the egg tested was 14 μg. Two days after the end of chelation therapy, results of a second blood lead test revealed a drop to nontoxic levels. No lead was detected in the combined yolks and albumen of eggs collected 7–11 days after the end of chelation therapy. Four weeks after the end of chelation therapy, no lead was identified in the shells of tested eggs.

An 8-year-old male yellow crowned Amazon parrot (Amazona ochrocephala) was presented for an 8-month history of intermittent regurgitation, anorexia, and lethargy along with a 3-week history of a soft tissue mass cranial to the vent. Examination revealed a small soft tissue mass, approximately 2 cm in diameter, within the body wall of the coelomic cavity with no discoloration of the surrounding tissue. Full body computed tomography (CT) revealed a defect in the body wall on the ventral coelom from the right paramedian location extending to the right side, which contained intestines. Surgical exploration allowed for reduction of the coelomic hernia, which was encased in fibrous tissue and contained a well-vascularized and motile loop of bowel. The hernia sac was excised before closing the body wall in a simple interrupted pattern. Three months postoperatively, the bird was reported to be doing well at home with no further episodes of regurgitation or anorexia.

A mixed thymoma was diagnosed in a 15-year-old female American robin (Turdus migratorius) that exhibited poor body condition, dysphagia, hyporexia, and depression. A 1.5-cm subcutaneous nodule was present in the cranio-ventral cervical region, which had been noticed by the owner 15 days before presentation. On cytologic evaluation of a fine-needle aspirate, well-differentiated lymphocytes were observed. Surgical excision was elected; however, the mass was firmly attached to the esophagus and the jugular vein, and the attempt at excision resulted in fatal hemorrhage. On histologic examination of the mass, small, well-differentiated lymphocytes were observed mixed with neoplastic reticular cells and Hassall's corpuscles. On immunohistochemical analysis, the cytoplasm of 80% of the reticular cells showed abundant detectable brown antigen binding with pancytokeratin staining, and most lymphoid cells showed detectable antigen in the cytoplasm by using CD3 antibodies. The cytologic, histopathologic, and immunohistochemical features of the neoplasm in this robin were consistent with a mixed thymoma.

A 25-year-old female yellow-naped Amazon parrot (Amazona auropalliata) was presented for an acute onset of lethargy, ptyalism, and regurgitation. Results of hematologic testing and plasma biochemical analysis revealed severe leukopenia and heteropenia with toxic heterophils and marked hyperamylasemia and hypoproteinemia, consistent with gastrointestinal dysfunction. Survey radiograph findings were suggestive of coelomic effusion. Results of a contrast-enhanced computed tomography (CT) scan revealed a tubular, irregularly marginated structure along the medial aspect of the duodenum, consistent with an inflamed pancreas. The bird died soon after CT imaging, and acute necrotizing pancreatitis and pancreatic coagulative necrosis were observed at necropsy. This report describes the use of a less-invasive modality such as CT to aid in the antemortem diagnosis of acute pancreatitis in a psittacine bird. Pancreatitis should be considered a differential diagnosis in birds with gastrointestinal signs and coelomic effusion visualized on radiography, and the observation of an enlarged inflamed pancreas in the absence of a defined pancreatic mass on CT.

A 30-year-old bald eagle (Haliaeetus leucocephalus) was presented with a history of hyporexia and lethargy. Results of initial hematologic testing, biochemical analysis, and fecal examination were unremarkable, and clinical signs did not resolve with supportive care and management changes. Results of echocardiography, based on auscultation of a murmur, and coelomic endoscopy, based on the presence of a soft tissue opacity on radiographs, as well as an aspergillosis panel were largely unsuccessful in determining a definitive diagnosis. Euthanasia was performed after the eagle did not recover from anesthesia after endoscopy. Necropsy results demonstrated bilateral testicular seminomas with metastases to the ventriculus. This case demonstrates an abnormal metastasis of a common reproductive tumor in an avian species.