A 24-year-old female secretary bird (Sagittarius serpentarius) was presented with acute, mild dyspnea occurring only during feeding times. Despite initial conservative therapy consisting of antibiotics and antifungal, antiparasitic, and anti-inflammatory drugs, the dyspnea worsened progressively, resulting in severe respiratory distress. Radiographs of the trachea suggested stenosis in the caudal one-third of the trachea. Tracheal endoscopy revealed an obstruction of approximately 90% of the tracheal lumen, in addition to mild suspected aspergillosis of the air sacs. Tracheal resection and anastomosis were performed, during which 1.5 cm of abnormal trachea was removed. Histopathologic examination showed severe granulomatous tracheitis, most likely induced by foreign body material. Respiratory signs resolved immediately postoperatively. Antibiotic and anti-inflammatory therapy continued for another 7 days and the bird was treated with antifungals for a total of 45 days. The bird recovered uneventfully. We encourage tracheal resection and anastomosis for severe tracheal stenosis even in aged, large birds of prey that are managed in large aviaries.

We determined the pharmacokinetic properties of ceftiofur crystalline-free acid (CCFA), a long-acting antibiotic, after a single intramuscular injection in cattle egrets (Bubulcus ibis). A dose of 20 mg/kg was administered intramuscularly to 18 birds and blood samples were collected via jugular venipuncture at 1, 2, 4, 8, 12, 24, 48, 72, 96, 120, 144, 168, 192, 216, and 240 hours after CCFA administration. Plasma concentrations of ceftiofur free acid equivalents (CFAEs) were measured via high-performance liquid chromatography. The minimum inhibitory concentration (MIC) of 1 μg/mL was reached by 1 hour after administration and remained higher than the MIC for at least 72 hours in all birds. This target concentration is effective for many bacterial infections in avian species. The area under the plasma concentration versus time curve was 451.3 h*μg/mL, maximum plasma concentration was 16.22 μg/mL, time to maximum plasma concentration was 3.2 hours, mean harmonic half-life was 37.92 hours, and time that the concentrations of CFAEs were higher than the target MIC was a minimum of 72 hours.

We evaluated the histomorphometry of the eye structures (cornea, retina, choroid, and sclera) of 13 adult free-living common kestrels (Falco tinnunculus). Birds included in the study were euthanatized because of severe trauma from a motor vehicle injury. The eyes were enucleated immediately after euthanasia, fixed in 10% buffered formalin, and decalcified. The right eyes were cut vertically (dorsoventrally) and the left eyes cut horizontally (temporonasally). Tissues were processed, stained with hematoxylin and eosin, and evaluated by an image analysis software. The thicknesses of the diverse corneal layers were measured at 3 points; 2 at the peripheral region (A and C) and one at the central region (B). The thicknesses of the retina, choroid, and sclera were evaluated at 6 different positions. Measurements of the left and right eyes of the male and female birds were compared. The median thicknesses of the cornea at the peripheral points were 210.78 (A) and 197.79 (C) μm, and 129 μm at the central point (B). The thickness of the cornea did not differ significantly between males and females or between right or left eyes. The mean thicknesses of the retina, choroid, and sclera were 91.13, 20.74, and 92.8 μm, respectively. The thickness of the choroid and sclera did not differ significantly between the sexes or between the right and left eyeballs. The retinas of the females were significantly thicker than those of males at the points in the fundus of the eyeball, near the insertion of the pecten (optical nerves).

A total of 3975 fecal samples, originated from the same number of individual birds, from 7 dedicated falcon hospitals, were examined to determine the prevalence of Caryospora species in the falcon population used in the sport of falconry in the United Arab Emirates (UAE). From that total, 297 (7.5%) were positive for the presence of Caryospora species. The falcons were all captive bred within the UAE and abroad, mainly from Germany, Spain, the United States, and Canada. Positive samples for the presence of Caryospora species were sporulated, and the taxonomy was established based on morphologic characteristics. The results showed the prevalence of the following Caryospora species: C kutzeri 41.4%, C neofalconis 25.6%, C megafalconis 18.2%, C falconis 10.4%, C cherrughi 3.7%, and C boeri 0.7%. The prevalence of Caryospora species among the various falcon species in this study was: gyr × peregrine hybrid falcons (Falco rusticolus × Falco peregrinus), 27.3%; gyr falcons (Falco rusticolus), 25.6%; peregrine falcons (Falco peregrinus), 20.5%; saker falcons (Falco cherrug), 16.5%; gyr × saker hybrid falcons (Falco rusticolus × Falco cherrug), 8.1%; Eurasian kestrels (Falco tinnunculus), 1%; red-napped shaheen (Falco pelegrinoides babylonicus), 0.7%; and American kestrels (Falco sparverius), 0.3%.

Two African grey parrots (Psittacus erithacus) and one hyacinth macaw (Anodorhynchus hyacinthinus) were examined because of varying clinical signs ranging from general lethargy to seizure-like episodes and regurgitation. Radiography and fluoroscopy in the 3 birds demonstrated variable degrees of gastric abnormalities, suggesting the presence of foreign material or stricture-like defects. Upper gastrointestinal rigid endoscopy by ingluviotomy revealed foreign bodies that were removed endoscopically. Minor postoperative complications were pulmonary congestion or mild aspiration and cardiac arrhythmia, both of which resolved, and no serious deleterious effects were associated with endoscopy in the short or long term. Endoscopy is recommended for examination and removal of foreign bodies from the upper gastrointestinal tract because it is less invasive and traumatic than traditional surgical approaches.

Macrorhabdus ornithogaster, avian gastric yeast, is a common cause of gastrointestinal disease in budgerigars (Melopsittacus undulatus). To better understand the clinical disease in budgerigars presented in a practice population, we reviewed the occurrence, clinical signs, and treatment success of M ornithogaster disease in budgerigars during a 2.5-year period at the Clinic for Birds and Reptiles, University of Leipzig (Leipzig, Germany). The yeast was diagnosed by microscopic examination of fresh fecal samples. Male budgerigars of all ages were most affected. Most clinical signs in birds with confirmed positive results were nonspecific, except for the occurrence of undigested seeds in the feces. Although radiographic appearance of a dilated proventriculus is indicative of a M ornithogaster infection, it is difficult to recognize because of the small size of the budgerigars. Birds with positive results were treated with amphotericin B (100 mg/kg PO q12h) for 4 weeks. Treatment was stressful for the birds because of the handling required and the long treatment duration, and therapeutic results were unsatisfactory. Therefore, the indications for treatment with amphotericin B should be carefully considered in birds with positive M ornithogaster results. An increased occurrence of the infection in association with other pathogens was detected.

Oropharyngeal swab samples were collected from 438 live racing pigeons (Columba livia), with and without signs of respiratory disease, that were housed in 220 lofts in 3 provinces in the western part of the Netherlands. Polymerase chain reaction (PCR) was used to identify Mycoplasma species and pigeon herpesvirus-1 (PHV-1) from the samples. In 8.6% of the pigeon lofts tested, signs of respiratory disease were present in pigeons at sampling, and in 30.9% of the sampled pigeon lofts, respiratory signs were observed in pigeons during the 6-month period immediately before sampling. A total of 39.8% of tested pigeons (54.5% of tested lofts) were positive for Mycoplasma species, and 30.6% of tested pigeons (48.6% of tested lofts) were positive for PHV-1. In 15.8% of the tested pigeons (26.8% of tested pigeon lofts), coinfection by Mycoplasma species and PHV-1 was identified. The number of pigeon lofts having pigeons coinfected by Mycoplasma species and PHV-1 was higher than that where only one of the infections was identified. Neither the presence of Mycoplasma species, PHV-1, nor the co-occurrence of both infections was significantly associated with signs of respiratory disease.

Twenty-nine wild Cape sugarbirds (Promerops cafer) died acutely after ingestion of a homemade xylitol nectar solution from a bird feeder. The most aggressive feeders were first affected. Most birds showed clinical signs within 15 minutes of nectar ingestion, including incoordination, weakness, falling from perches, collapse, and death. A few birds showing clinical signs seemed to spontaneously recover and fly away. Full necropsy examinations done on 27 birds were hampered by freezing artifact and autolysis, but results indicated death was caused by the consequences of acute hypoglycemia. A presumptive diagnosis of xylitol toxicity was made based on the history, clinical signs, and absence of other obvious causes of death. This is potentially the first record of xylitol toxicity in wild birds.

Fatal clostridial infections and clostridial toxicoses are common in birds. Most fatalities are associated with toxin production and progress rapidly, often within 24 hours of infection. We describe an unusual and protracted course of disease in 6 captive brown pelicans (Pelecanus occidentalis), which was believed to result from toxicosis by toxovar A produced by a mixed infection with Clostridium sordellii and Clostridium perfringens. Although the first death in the group occurred 3 days after signs of illness were documented, the remaining birds died over a 38-day period despite aggressive antibiotic and supportive therapy. Although the birds presented with classic signs of botulism, Clostridium botulinum was not identified in any tissues or environmental samples. Postmortem findings in all pelicans included extensive subacute myonecrosis, enteritis, and nonsuppurative hepatitis. Alpha-toxins and sordellilysin genes from C perfringens and C sordelli isolates, respectively, were detected via polymerase chain reaction. The source of the pathogenic bacteria was sediment within a water basin inside the affected birds' enclosure.

A 15-year-old female blue and gold macaw (Ara ararauna) was presented for evaluation after being found laterally recumbent, reluctant to move, and lethargic. Results of a complete blood count showed an increased number of immature heterophils with increased cytoplasmic basophilia and degranulation and the presence of a left shift. Radiographs and a computed tomography scan were performed and revealed a markedly enlarged spleen. An ultrasound-guided fine-needle aspirate of the spleen was submitted for cytologic examination and aerobic bacterial culture. While the culture revealed no growth, cytologic examination identified mononuclear phagocytes with cytoplasmic vacuoles containing structures consistent with bacteria. Pan-bacterial 16S rRNA polymerase chain reaction of the splenic sample followed by direct sequencing identified a Coxiella-like agent identical to one previously isolated in the liver of a golden-mantled rosella (Platycercus eximius). Phylogenetic analysis shows that avian coxiellosis agents and Coxiella burnetii, the agent of Q fever, represent 2 independent events of development of vertebrate pathogenicity in this group of tick endosymbionts. This report suggests diagnostic and treatment directions for coxiellosis in avian patients and indicates where further study is needed.

An approximately 10-year-old, female Congo African grey parrot (Psittacus erithacus erithacus) developed progressive, unilateral exophthalmos and buphthalmos. Survey radiographs revealed a large, coelomic, soft tissue mass, which was confirmed on computed tomography scan. Aspirates of both the contents of the buphthalmic globe and coelomic mass were consistent with Cryptococcus species. Initial results were later confirmed with serum antigen latex agglutination and polymerase chain reaction testing, and the organism was then identified as Cryptococcus neoformans with DNA sequencing. During the course of 1 year, the bird was treated with combinations of oral terbinafine, fluconazole, and flucytosine, as well as intraocular amphotericin B. The coelomic mass dramatically decreased in size during the course of treatment, but the globe continued to enlarge. The bird died after exhibiting ataxia and seizures approximately 13 months after initial diagnosis, and necropsy confirmed colonization of the cerebrum and meninges with Cryptococcus. Cryptococcus remains a rare fungal disease of birds that is often refractory to treatment.

We would like to acknowledge and extend our sincere gratitude to the following people for contributions of their time, expertise, and guidance as reviewers of manuscripts for the Journal of Avian Medicine and Surgery from November 23, 2016 through November 14, 2017.