“Young bird sickness” is a term used by racing pigeon fanciers to describe a condition that has occurred regularly in recent years and affects pigeons (Columba livia domestica) in their first year of life. It is characterized by slow crop emptying, regurgitation, diarrhea, weight loss, poor performance, and occasionally death. Little scientific information is known about this syndrome to differentiate it from other diseases that occur in young pigeons. In this study, 1 bird from each of 9 lofts where “young bird sickness” was reported was euthanatized for cytologic and postmortem examination. Lesions of the lymphoreticular system, alimentary tract, and respiratory system were the most common findings. Lesions of the lymphoreticular system were present in all birds examined, and 3 birds had histopathologic findings consistent with circovirus infection. Combinations of protozoal, fungal, and mixed bacterial infections were associated with ingluvitis in 7 birds and enteritis in 6 birds. Pneumonitis was found in 5 birds that tested positive for Chlamydophila by polymerase chain reaction. Although “young bird sickness” appears to be a multifactorial condition, a pattern of lesions that involved the lymphoreticular, gastrointestinal, and respiratory systems was evident, whereas diseases of other organ systems were uncommon. These findings suggest that “young bird sickness” may have a common etiology, and circovirus infection is proposed as a possible initiating cause of this syndrome in young racing pigeons in Northern Ireland.

Clinical signs of renal disorders in animals, including raptors, are not specific. Furthermore, serum or plasma biochemical parameters change only when 70% of kidney function is lost. In this study, reference values of urine variables were established in clinically healthy falcons. Urine samples were collected from 78 mature (>1 year) and immature (6–12 months) male and female falcons belonging to 5 species. Droppings were assessed visually for urate color and consistency and color of the liquid urine. The liquid urine was collected by aspiration into a syringe and centrifuged, and the supernatant analyzed by commercial dipstick and by a wet chemistry analysis for alkaline phosphatase, gamma glutamyl transferase, glucose, chloride, and total protein concentrations. Sex, age, and species did not affect results of biochemical urine values (P > .05). Urine biochemical values did not differ significantly between fasted and fed birds. Total protein levels in urine samples decreased after 24-hour storage at 4°C. Reference ranges for clinically normal birds are reported.

In wild birds implanted intracoelomically with radio transmitters, a synthetic fabric collar placed around the base of a percutaneous antenna is believed to function as a barrier to contamination of the coelom. We examined 13 fabric collars recovered from percutaneous antennas of radio transmitters implanted intracoelomically in harlequin ducks (Histrionicus histrionicus) 12 months earlier. Both the transmitters and antenna collars were encapsulated in fibrous connective tissue, with adhesions to internal organs. Histologically, bacteria were evident at the fabric-plastic interface in 8 of 10 collars examined in cross section and along the length of the collar in 3 collars examined longitudinally. Bacteria were confined within the fibrotic sheath surrounding the transmitter and the antenna collar in all birds. No evidence of chronic systemic effects secondary to implantation was present on hematologic or serum biochemical testing. These findings indicate that antenna collars do not prevent the entry of bacteria along the percutaneous antenna but may help stabilize the antenna and minimize coelomic contamination. We conclude that radio transmitters implanted into the coelom of harlequin ducks do not appear to cause significant health problems for at least 1 year after implantation.

To evaluate a minimally invasive endosurgical system in birds, endoscopic orchidectomy and salpingohysterectomy were evaluated in 11 male and 14 female pigeons (Columba livia). Anesthesia was maintained by using isoflurane delivered by a pressure-cycle ventilator and produced good to excellent anesthesia during 96% of procedures. Endosurgery was performed with a 2.7-mm telescope system, 3-mm human pediatric laparoscopy instruments, and a 4.0-MHz radiofrequency device. Mean ± SD surgery times for bilateral orchidectomy and salpingohysterectomy procedures were 39 ± 18 minutes and 34 ± 15 minutes, respectively. Procedures were generally straightforward, with any minor complications easily overcome. Surgical complications were generally minor, with mild hemorrhage and focal coagulative damage to the kidney being most common. All pigeons recovered quickly (20 ± 11 minutes), with 95% displaying good to excellent recoveries. No birds exhibited any clinically apparent morbidity or mortality associated with endosurgery. At least 1 male and 1 female bird were subjected to elective euthanasia and necropsy on postoperative days 1, 3, 5, 10, 20, and 90 to determine the success and side effects of surgery. Gross and histologic abnormalities, when observed, were generally mild, with hemorrhage and partial necrosis of the cranial kidney present in 27% of males. Mild damage or hematoma associated with the left kidney was also reported in 28% of females. The surgical objectives were achieved in 23 of 25 pigeons. The 2 surgical failures (regenerated testes in a male and large oviductal remnant in a female) were attributed to endosurgical inexperience and occurred during the first procedures. Salpingohysterectomy does not appear to prevent ovarian development and ovulation in the pigeon, at least not during the first 3 postoperative months. Orchidectomy and salpingohysterectomy appear to be safe procedures when performed using appropriate equipment and techniques. Endosurgery offers a valuable, minimally invasive alternative to the standard coeliotomy techniques commonly used in birds.

Hornbills are distinguished from most other avian taxa by the presence of a casque on the dorsal maxillary beak, which, in all but 1 of the 54 extant hornbill species, is described as essentially an air-filled cavity enclosed by minimal cancellous bone. The external casque has been described in detail, but little has been described about its internal anatomy and the communications between the casque and the paranasal sinuses. In this study, 10 intact casque and skull specimens of 7 hornbill species were collected opportunistically at necropsy. The anatomy of the casque and the skull for each of the specimens was examined by radiography, contrast radiography, and computed tomography. After imaging, 8 specimens were submitted for osteologic preparation to directly visualize the casque and the skull interior. Through this standardized review, the baseline anatomy of the internal casque was described, including identification of a novel casque sinus within the paranasal sinus system. These observations will assist clinicians in the diagnosis and treatment of diseases of the casque in hornbill species.

A natural outbreak of avipoxvirus occurred in recently purchased stone curlews (Burhinus oedicnemus) at a breeding farm and subsequently spread to other stone curlews residing at the farm. The initial outbreak was characterized by mild vesicular skin lesions on the legs, which then developed crusts and bled. The overall morbidity rate was 100%, but none of the birds died, and all recovered without complication. Four gallinaceous species, also kept on the farm, did not develop lesions. Avipoxvirus was identified from the skin lesions by virus isolation, electron microscopy, and monoclonal antibody testing, as well as by polymerase chain reaction testing. Eight months after this outbreak, 7 male stone curlews developed large, round, crusty lesions on their legs. Although poxvirus virions were identified in the lesions, results of virus isolation were negative. These lesions possibly were the result of a recrudescence of the original infection in male birds that were stressed because they were housed together during the breeding season. This is the first clinical description of an avipoxvirus infection in stone curlews.

A 16-year-old male grey-cheeked parakeet (Brotogeris pyrrhopterus) was presented for dyspnea and decreased activity. The bird's diet was primarily table food, with a large proportion of animal products. Radiographs revealed a linear mineralized structure in the plane of the aorta and an enlarged hepatocardiac silhouette. Left atrial and left ventricular enlargement and a left ventricular systolic dysfunction were diagnosed by echocardiography. The bird's condition progressively declined, and it died 5 days after presentation. A postmortem examination revealed marked atherosclerosis of the aorta, great vessels of the heart, and coronary arteries with myocardial degeneration, pulmonary congestion, and ascites. Little is known about the risk factors of atherosclerosis in psittacine birds, and dietary influence, if any, is not understood.

This report describes the author's experiences in participating in avian research during 3 field seasons in remote areas in Prince William Sound (PWS), located in south-central Alaska. Veterinary support was needed to biopsy the livers of nestling and adult pigeon guillemots (Cepphus columba) and adult black oystercatchers (Haematopus bachmani). These surgeries were part of larger research studies investigating guillemot and oystercatcher populations and possible continued exposure to residual crude oil in the marine environment after the Exxon Valdez oil spill in PWS in 1989.

When we are asked what we do as veterinarians, most of us would answer, on a basic level, that we help ensure animal health. Usually this is what the owners, our clients, want us to do. This task may be complicated when the client is a pet store. Although pet stores also want to protect their animals' health, concerns over the cost of pet health care, the potential for disease transmission among pets, and legal implications of selling sick pets may affect a pet store's decision to treat an ill animal. In addition, veterinarians generally try to aid pet stores with the hope of obtaining referrals from these stores once pets are sold; however, in helping these stores, veterinarians may be asked, at times, to compromise their ethics.

In this round table discussion, I asked 4 veterinarians who routinely deal with pet stores to describe these interactions. The participants are Steve Metz, DVM, Shelburne Veterinary Hospital, Shelburne, VT, USA; Martin Randell, DVM, Dipl ACVIM, Somers Animal Hospital, Somers, NY, USA; Gregory Rich, DVM, West Esplanade Veterinary Clinic, Metairie, LA, USA; and Ken Welle, DVM, Dipl ABVP (Avian Practice), All Creatures Animal Hospital, Urbana, IL, USA. Their experiences with pet stores are both frustrating and rewarding. I hope they will make us all reflect our past interactions with pet stores and help guide us in our future pet store relationships.