The aim of this study was to identify possible predisposing anatomical factors associated with humeral fractures in birds of prey through comparison of specific anatomical features in different raptor species. An anatomical study of bone features in birds of prey was performed on 3 male subjects from 5 different species. The selected species included in this investigation were 3 diurnal species (the common buzzard [Buteo buteo], the peregrine falcon [Falco peregrinus], and the European honey-buzzard [Pernis apivorus]) and 2 nocturnal species (the barn owl [Tyto alba] and the tawny owl [Strix aluco]). Humeral bone samples were tomographically analyzed with a micro–macro-focus computed tomographic machine. Specific humeral anatomical points were selected (foramen pneumaticum and tuberculum dorsale for the proximal humerus; corpus humeri for the diaphyseal humerus; and above the condylus dorsalis for the distal humerus) to measure foramen pneumaticum diameter (in millimeters), cortical thickness (in millimeters), and trabeculae number and sizes (in millimeters). Apparent density, measured with the Hounsfield unit, was used to assess the degree of bone resistance. Statistical analysis was performed with a Spearman's correlation, and significance was set at P < .05. The differences among the observed bone volumes were highly significant (P = .00). Trabeculae number and the humeral anatomical point measurements showed differences in all 5 avian species investigated. However, those differences were not significant, except at the condylus dorsalis; in which, a significant interspecies difference (P = .002) was recorded. Trabecular size, cortical thickness, bone density, and diameter of the foramen pneumaticum were all different in all raptor species; however, these variations were not significant. The study confirms the existence of humeral bone volume differences between diurnal and nocturnal species. Furthermore, the data suggest that the humeri of peregrine falcons and European honey-buzzards may be stronger than the humeri of common buzzards, tawny owls, and barn owls.

The effects of season, location, species, and sex on body weight and a comprehensive array of blood chemistry and hematology analytes were compared for free-ranging western (Aechmophorus occidentalis) and Clark's (Aechmophorus clarkii) grebes. Birds (n = 56) were collected from Puget Sound, WA, and Monterey Bay and San Francisco Bay, CA, from February 2007 to March 2011. The data supported generalization of observed ranges for most analytes across Aechmophorus grebe metapopulations wintering on the Pacific coast. Notable seasonal and location effects were observed for packed cell volume (winter 6% greater than fall; winter California [CA] 5% greater than Washington [WA]), total white blood cell count (CA 3.57 × 10³ cells/µL greater than WA), heterophils (WA 10% greater than CA), lymphocytes (winter 19% greater than fall), heterophil to lymphocyte ratio (fall 5.7 greater than winter), basophils (CA greater than WA), plasma protein (WA about 10 g/L [1.0 g/dL] greater than CA), plasma protein to fibrinogen ratio (winter about 15 greater than fall), potassium (CA 2 mmol/L greater than WA), and liver enzymes (alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase: WA greater than CA). Within California, season had a greater effect on body mass than sex (mean winter weights about 200 g greater than fall), whereas within a season, males weighed only about 80 g more than females, on average. These data give biologists and veterinarians quantitative reference values to better assess health at the individual and metapopulation level.

Amlodipine is a calcium channel blocker shown to be effective in lowering blood pressure with minimal adverse effects in mammals. To provide a retrospective evaluation of amlodipine use in psittacine birds, medical records were reviewed for all avian patients prescribed amlodipine for treatment for the presumptive diagnosis of hypertension, based on clinical signs and indirect blood pressure measurements. Five birds were treated with amlodipine between 2010 and 2018. The median age was 33 years (range, 22–37 years) and 3/5 birds presented for ataxia or seizures. The median indirect systolic blood pressure at diagnosis was 243 mm Hg (range, 200–275 mm Hg). In 3/5 birds, amlodipine was the only drug prescribed, whereas, in 2/5 birds, enalapril was also prescribed in addition to amlodipine. In addition to the prescription of enalapril, blood pressure measurements were obtained indirectly, which are variables to be considered in this report. The initial median dose of amlodipine prescribed was 0.4 mg/kg (range, 0.1–0.4 mg/kg) PO q24h. In 3/5 birds, amlodipine administration was increased either in dose or frequency. Median follow-up time was 25 months (range, 2–55 months) after the initiation of amlodipine treatment. Owners in all 5 cases reported improvement of clinical signs by a median time of 2 months (range, 1–15 months). Three of 5 birds (60%) demonstrated a decreasing trend in blood pressure during the first 6 months after treatment with amlodipine was started (average, ≥20% decrease). Prospective, controlled studies are needed to investigate the efficacy of amlodipine in psittacine birds.

Alfaxalone is an injectable neuroactive steroid anesthetic that is becoming more widely used as a sedative in a wide range of animals. The purpose of this study was to evaluate the efficacy of this drug for sedation during handling and noninvasive medical procedures in black-cheeked lovebirds (Agapornis nigrigenis). Based on a pilot study that showed that 5 mg/kg alfaxalone was inadequate, and that 20 mg/kg resulted in respiratory arrest in 1 bird, the effects of 12.6 ± 0.9 mg/kg alfaxalone administered subcutaneously was investigated in 9 birds. Despite minor movements and twitching, it was possible to handle all birds and to perform positioning for a ventrodorsal radiograph. A loss of reaction to noxious stimuli was not achieved during sedation. Times from injection to initial effect (mean ± SD) was 93 ± 48 seconds; to recumbency, 209 ± 70 seconds; to first handling for positioning the bird in lateral recumbency, 251 ± 68 seconds; to initial righting effort, 55 ± 8 minutes; and to perching for a minimum of 20 seconds, 76 ± 7 minutes. Median respiration rates between 5 to 45 minutes were 36 to 40 breaths/min; apnea was not noted in any bird. Birds received 0.5 L of oxygen/min via face mask. Oxygen saturation (SpO₂) and pulse rate were measured via pulse oximetry in 8 birds continuously from 10 to 30 minutes, SpO₂ values remained above 90%. During sedation, mean pulse rate decreased significantly over time (P = .007; 10 minutes = 409 ± 81 beats/min; 30 minutes = 324 ± 25 beats/min). The majority of birds had rough inductions and recoveries, which could have been minimized if birds had been placed in a more confined space. In summary, 12.6 mg/kg alfaxalone provided nearly 1 hour of stable, nonanalgesic sedation appropriate for noninvasive procedures in black-cheeked lovebirds.

The effects of an injectable anesthesia with 0.05 mg/kg medetomidine, 5 mg/kg ketamine, and 0.5 mg/kg butorphanol administered together intramuscularly were evaluated in 22 captive Humboldt penguins (Spheniscus humboldti, 10 male and 12 female), with a mean age of 8.5 ± 8.23 years. The birds fasted for18–24 hours prior to the procedure. Induction was followed by 4 distinct progressive responses of the birds to the anesthetic effect, including onset of initial effects at 2.0 ± 1.7 minutes (x̄ ± SD), sternal recumbency with the head still elevated at 2.2 ± 1.6 minutes, lowering and placing the beak tip to the ground at 3.6 ± 3.4 minutes, and lateral positioning of the neck and head at 4.2 ± 3.4 minutes. A general state of sedation, muscle relaxation, and analgesia were noted 10.0 ± 2.8 minutes postinjection. However, according to an established scoring system for the assessment of anesthetic depth in avian patients, a surgical plane of anesthesia was not achieved. Muscle relaxation determined by the same scoring system lasted for 31.4 ± 17.1 minutes. The penguins' mean respiratory rate did not demonstrate significant change and spontaneous ventilation was present throughout the procedure. Relative peripheral arterial oxygen saturation decreased significantly from 92.83 ± 5.77% at 10 minutes to 90.91 ± 5.77% at 40 minutes following induction. The birds' heart rate also decreased significantly from 112.55 ± 23.97 beats/min at 10 minutes to 101.65 ± 25.42 beats/min at 40 minutes. The measured cloacal temperatures were maintained within normal range despite ambient temperatures of up to 28.3°C (82.9°F). Reversal of medetomidine with 0.25 mg/kg atipamezole was conducted after 45.1 ± 7.3 minutes. Recovery was smooth but of variable duration with patients being able or willing to stand steadily in an upright position after 50.1 ± 34.6 minutes. One penguin died during recovery from a ruptured left ventricle and consecutive pericardial tamponade, but no predisposing factors were identified. The anesthetic protocol proved to be effective for noninvasive and minor painful procedures (eg, diagnostic imaging, blood collection). Disadvantages to the administration of the combined anesthetic agents in the penguins included a short period of muscle relaxation and smooth but potentially prolonged recovery. The safety of the anesthetic protocol described for Humboldt penguins in this report has to be evaluated critically against the the death of 1 penguin during recovery.

Electrophoresis can be used to aid in the diagnosis of infectious diseases (eg, aspergillosis) in avian species. Reference intervals for blood plasma proteins of 2 different flamingo species (Phoenicopterus roseus and Phoenicopterus ruber) and their hybrids were calculated by capillary zone electrophoresis (CZE) and differences between these species, sexes, and age groups were evaluated. Lithium-heparinized plasma samples from 111 animals from a zoological collection were analyzed by CZE and statistically evaluated. Differences were only found between greater and American flamingos (P = .003) and between greater flamingos and hybrids (P = .001) in the γ-globulin fraction. Male greater flamingos showed significantly higher α-globulins (P = .022) and females higher total albumin by CZE (P = .037). In American flamingos, the percent total albumin (P = .017), total albumin (P = .025), prealbumin (P = .005), and albumin/ globulin (A/G) ratio (P = .008) were higher in females, and α- (P = .023) and β-globulins (P = .021) were higher in males of the same species. The following parameters differed significantly between the age groups: γ-globulins (P = .048) in greater and α- (P = .021) and β-globulins (P = .001) in American flamingos increased with increased age and percent total albumin (P = .002), total albumin (P = .024), and A/G ratio (P = .002) decreased with age in American flamingos. The results showed only small differences between the species, but greater differences between the sexes and ages, especially in American flamingos, which must be considered when interpreting laboratory results.

This study compared the use of radioimmunoassay (RIA) and chemiluminescent immunoassay (CLIA) to measure serum thyroid hormone levels in green-winged macaws (Ara chloropterus). The sample group comprised 20 male and 13 female (n = 33) healthy, captive green-winged macaws of reproductive age but outside of breeding season. Mean free triiodothyronine (T3), total T3, and free thyroxine (T4) measured by CLIA and RIA corresponded to 5.11 and 5.08 pmol/L (3.33 and 3.31 pg/mL), 1.59 and 1.56 nmol/L (103.5 and 101.5 ng/dL), and 8.25 and 8.82 pmol/L (0.64 and 0.69 ng/dL), respectively. Mean total T4 by RIA corresponded to 6.29 nmol/L (0.49 µg/dL). Mean free T4 and thyroid-stimulating hormone (TSH) levels differed according to immunoassay method, with higher values measured by RIA compared with CLIA. Sex influence was statistically significant in immunoassay results only on free T3 levels. Free T3 levels measured by RIA were higher than levels measured by CLIA in male birds, but this difference was not found with the female bird samples. Conversely, free T3 levels measured by CLIA were higher in the female macaws compared with male birds. Comparative analysis of thyroid hormone measurements in this study revealed that RIA and CLIA are equivalent methods to measure free T4 and total T3 levels but not TSH levels. These findings support the use of CLIA for free T4 and total T3 level determinations in green-winged macaws. However, the CLIA kit used in this study provided invalid total T4 level results for the macaws sampled. Radioimmunoassay and CLIA were equally ineffective for determining TSH levels in this species.

Atherosclerosis is frequently diagnosed in captive parrots. Recent studies have highlighted the potential role of high fructose intake in the development of human cardiovascular disease. The objective of this study was to investigate the effects of dietary fructose on the lipid profile in psittacine birds. Six macaws, composed of 3 green-winged macaws (Ara chloropterus, 2 females, 1 male), and 3 blue-and-gold macaws (Ara ararauna, 1 female, 2 males), ranging from 15 to 26 years of age, were used as subject animals for this dietary investigation. Initially, fruits were removed from the diet and replaced with vegetables lower in fructose for a month. Then, with a crossover study design, each bird was randomly selected to receive either 34 kcal of a fructose solution daily for 5 days then an equivalent volume of water for 5 days, or water in the first 5 days followed by the 34 kcal fructose solution. Lipid profiles were repeatedly performed over the course of the study at specific intervals. Serum cholesterol (3.01–5.55 mmol/L), triglycerides (0.27–2.70 mmol/L), high-density lipoprotein–cholesterol (1.43–4.79 mmol/L), low-density lipoprotein–cholesterol (0.02–0.85 mmol/L), and very low density lipoprotein–cholesterol (0.12–1.22 mmol/L) levels were not statistically significantly different over time and treatment. Although no significant effect could be demonstrated in this study, further studies are needed to investigate the effect of a high fructose intake in psittacine birds, because it could have a deleterious influence on their cardiovascular health if proven to be linked with dyslipidemia as reported in humans. Higher amounts of fructose and longer periods of administration should be considered for future studies.

A 32-year-old captive female Chilean flamingo (Phoenicopterus chilensis) was diagnosed with a hypermature resorbed cataract in the right eye and a mature cataract with phacolytic uveitis in the left eye. No other systemic or neurologic physical abnormalities were detected. The patient was considered blind from bilateral cataracts, and with a reduced quality of life, surgery was indicated to remove the mature cataract in the left eye. Before surgery, the phacolytic uveitis was treated in the left eye for 1 week with topical and systemic anti-inflammatory and antibiotic medication. Unilateral phacoemulsification was performed on the left eye while under general anesthesia. The individual recovered uneventfully and regained vision in the left eye. The bird was returned to its enclosure 8 days after the surgical procedure. No abnormalities were noted in behavior or reintegration. Three weeks after the phacoemulsification was performed in the left eye, the individual presented with active uveitis, without vision loss, suspected secondary to incisional infection, which was managed with topical and systemic anti-inflammatory and antibiotic medication. At day 41 the patient was discharged with no disease conditions affecting the left eye, and the flamingo's vision was considered significantly improved compared with initial presentation. Phacoemulsification was safe and effective in removing the lens, resolving phacolytic uveitis, and restoring vision in spite of the postsurgical incisional infection. Some adaptations in the surgical approach and medical management are recommended on the basis of morphology, feeding habits, and behavior of this aquatic avian species to avoid postsurgical incisional infection and uveitis.

An Atlantic yellow-nosed albatross (Thalassarche chlororhynchos) was found on shore 3 days after having been captured at sea by researchers. It presented very lethargic, moderately dehydrated, and in poor body condition. It was mildly hypothermic, with moderate pediculosis, and dark malodorous feces with yellow urates. The bird had a 48-g satellite transmitter attached with a backpack-style chest harness, which caused an ulcerative lesion on the interscapular area. The bird was severely anemic (packed cell volume, 18%), and plasma chemistry results were suggestive of a severe rhabdomyolysis (aspartate transaminase, 3620 U/L; creatine kinase, 100 400 U/L). We hypothesized that capture myopathy occurred because of a combination of capture stress and prolonged physical restraint by researchers, stress associated with repeated attempts by the bird to remove the satellite-transmitter harness, and a lengthy road transport to the rehabilitation center. A treatment protocol, which relied on a combination of aggressive fluid therapy, selenium, vitamins E and B₁₂, and multivitamin supplementation, was administered after the initial physical assessment of the albatross. Isoflurane inhalation anesthesia was used to minimize stress associated with the performed medical procedures (eg, physical examination, removal of the satellite transmitter harness, blood collection, and wound management). Measures were adopted while the bird was hospitalized to reduce stress (eg, quiet and comfortable environment with visual barriers and restricting handling of the patient to experienced staff). Clinical and hematological monitoring was used to assess the patient's condition as the bird gradually recovered while hospitalized. The albatross was successfully released 28 days after the initial presentation, suggesting that the medical protocol employed in this case may be useful for the treatment of capture myopathy in albatrosses and other birds.

A 26-year-old, male eclectus parrot (Eclectus roratus) was presented to its primary care veterinarian for a 10-day history of increased respiratory effort, lethargy, and a single episode of regurgitation. Hepatomegaly, proventricular enlargement, cranial displacement of the ventriculus, and coelomic effusion were suspected based on a 1-view radiographic image, and the patient was referred for further evaluation. On presentation to the referral veterinary hospital, a distended coelom and dyspnea with abnormal respiratory sounds were abnormalities noted upon physical examination of the patient. The bird was hospitalized for supportive care, and diagnostic tests were performed. Initial radiographic images at the referral hospital revealed a large intracoelomic mass. A computed tomographic scan was performed; however, the origin of the mass could not be determined. A fine-needle aspirate and cytologic evaluation of the intracoelomic mass revealed a neoplastic process but no specific tissue type. Two days after presentation to the referral hospital, an exploratory coeliotomy to surgically resect the mass was attempted. The mass occupied most of the coelomic cavity, with multiple adhesions to internal organs. The mass was successfully resected; however, the patient destabilized and died despite resuscitation efforts. Histopathologic examination of submitted tissue from the mass with immunohistochemistry revealed mixed populations of neoplastic cells differentiated from 3 primordial germinal layers, confirming the diagnosis of teratoma. Teratomas appear to be a rare tumor in avian species but should be included in a list of differential disease diagnoses for abnormal tissue masses of unknown origin. Only 2 cases of teratomas have, to our knowledge, been reported in psittacine species.

An approximately 25-year-old, female, yellow-naped Amazon parrot (Amazona auropalliata) was evaluated for a chronic, raised, ulcerative mass on the lateral aspect of the left thigh. Histopathology of an excisional biopsy revealed severe, chronic, multifocal-to-coalescing, ulcerated dermal and subcutaneous granulomas. No infectious organisms were observed on Ziehl-Neelsen or Gomori methenamine silver stains. The parrot was treated with oral sulfamethoxazoletrimethoprim and meloxicam. When reexamined 2 weeks later, the biopsy site had healed. Surgical biopsies were resubmitted 14 months after the original presentation due to recurrence of similar ulcerative lesions on the right leg. Histopathology revealed a similar inflammatory pattern, and hematoxylin-eosin, Ziehl-Neelsen, and silver stains on the biopsy samples were all negative. A Fite-Faraco stain revealed rare acid-fast bacilli throughout the lesion. Tissue polymerase chain reaction test was negative for Mycobacterium avium and Mycobacterium genavense. Mycobacterial culture and subsequent genotyping revealed Mycobacterium kansasii. Mycobacterium kansasii is a significant cause of mycobacteriosis in humans and, therefore, should be considered a potential zoonotic organism. This report describes an unusual primary cutaneous presentation of avian mycobacteriosis.