JOURNAL OF AVIAN MEDICINE AND SURGERY

Evaluation of a Point-of-Care-Viscoelastic Coagulation Device in Hispaniolan Amazon Parrots ()
Russell L, Tully TN, Smith MR and Mitchell MA
Viscoelastic testing evaluates the formation and lysis of a clot over time, allowing more complete assessment of patient hemostasis in real time, whereas traditional tests, such as prothrombin time and partial thromboplastin time, only measure coagulation factor function. Patient-side viscoelastic coagulation monitors are easy to use, portable, and provide faster turnaround time than commercial laboratories. Viscoelastic testing requires only 0.2 mL of blood and is useful in diagnosing and treating hemostatic disorders. Currently, there is no standardized coagulation testing method across bird species. In this cross-sectional study, a viscoelastic coagulation device, the Entegrion Viscoelastic Coagulation Monitor-Vet (VCM-Vet), was evaluated. Blood samples were obtained from 26 Hispaniolan Amazon parrots (HAPs) () under manual restraint. Results were recorded on the device as graphical output with quantitative viscoelastic measurements. Results were reported using standard rotational thromboelastometry terminology, including clotting time, clot formation time, alpha angle, maximum clot firmness, clot firmness amplitude at 10 and 20 minutes after clot formation, and clot lysis at 30 and 45 minutes. The median clotting time was 463 seconds (reference interval: 56-1635 seconds), the mean clot formation time was 704.7 seconds (reference interval: 172-1697 seconds), the mean alpha angle was 27.3 (reference interval: 7-60), and the mean maximum clot firmness was 15.4 (reference interval: 7-25). Statistical analysis found that all parameters were normally distributed aside from clotting time in seconds. There was no appreciable breakdown of the clot during the 60-minute device runtime, and there was no significant difference in any parameter based on sex. The VCM-Vet produced clotting times for this population of HAPs and enabled the creation of reference intervals. Based on our findings, the VCM-Vet can be used to assess clot potential in HAPs and possibly other avian species.
Successful Management of Acetamiprid Intoxication in a Captive Eurasian Goshawk ()
d'Ovidio D and Wernick MB
A captive, 1-year-old, male Eurasian goshawk () weighing 0.85 kg and owned by a falconer was presented with a history of acute onset of weakness, dyspnea, diarrhea, and regurgitation of a fresh-thawed pigeon contaminated with acetamiprid, an insecticide used in the raptor enclosure. The raptor had eaten the contaminated pigeon approximately 10-12 hours earlier. Two-view (lateral and ventrodorsal) full-body survey radiographs were taken, and no abnormalities were noted. A complete blood count and serum biochemistry panel showed increased concentrations of hematocrit, uric acid concentrations, and creatine kinase activity. Intravenous isotonic crystalloid fluids, oxygen supplementation, active warming, and assist feeding by oral syringe were provided. The bird rapidly improved approximately 12 hours after initiating supportive care. Complete resolution of clinical signs and return of normal appetite occurred within 2 days of hospitalization. No recurrence of clinical signs was reported in the raptor presented on 2 months' follow-up. The outcome of this case suggests that supportive treatment of acetamiprid toxicity in captive goshawks can be successful with early intervention.
Effect of Capromorelin on Appetite and Weight Gain of Domestic Pigeons ()
Trumpp K, Burns L, Jacobson C and Divers SJ
Weight loss and decreased appetite are commonly encountered sequela of disease and stress in avian patients. However, there is currently minimal information in the veterinary literature regarding appetite stimulation in birds. Capromorelin is a potent agonist of the growth hormone secretagogue receptor and increases food consumption via direct stimulation of the hunger centers of the hypothalamus. It is US Food and Drug Administration approved for use as an appetite stimulant in dogs () and has also been shown to increase food consumption in New Zealand white rabbits (), domestic cats (), and chickens (). Twenty adult domestic pigeons (), housed in groups of 5, were involved in a randomized controlled study to investigate the effect of capromorelin on appetite and weight gain. Each group of pigeons was randomly assigned to receive either oral water (control) or capromorelin (treatment). The birds were individually weighed and given either oral water (control) or capromorelin at 12 mg/kg once daily for the duration of the 6-day study period. Total food consumed was recorded in grams per cage each day, and pigeons given capromorelin consumed 38% more food than those in the control group. Pigeons given capromorelin gained significantly more weight (2.5% gain) over the course of the study period compared with controls (0.7% loss, = 0.004). No adverse side effects were noted in any birds. Capromorelin shows promise as an appetite stimulant in pigeons, and further investigation into its use in other avian species is warranted.
Use of Haloperidol in Companion Psittacine Birds: 19 Cases (2012-2022)
Hausmann Farris KE and Doss GA
The antipsychotic medication haloperidol has been used for many years in avian medicine as a pharmacologic therapy for refractory feather destructive behavior in pet parrots. However, despite its common use, there are no published studies evaluating its efficacy and adverse effects in psittacine birds. The goal of this study was to report the signalment, clinical presentation, dosing regimen, response to therapy, and adverse effects of companion psittacine birds prescribed oral haloperidol therapy at a single veterinary referral hospital. Included cases were pet psittacine birds that were prescribed haloperidol between 2012 and 2022 and had sufficient follow-up information available to assess efficacy and adverse effects. Nineteen parrots met the case criteria for inclusion. Haloperidol was prescribed for 17 birds with feather destructive behavior, 1 bird for excessive sexual behavior, and 1 bird prophylactically after surgery of the uropygial gland. The most common species prescribed haloperidol were grey parrots (n = 5) (), umbrella cockatoos (n = 4) (), and spp. (n = 2). Most (12/18 [67%]) birds were classified as having a positive response to haloperidol administration. The initial median (interquartile range) total daily dose for all birds in the study was 0.24 mg/kg (0.18-0.4 mg/kg). Adverse effects were reported in 9/19 (47%) birds with grey parrots being the most common species displaying adverse effects. The most common adverse effect reported was lethargy in 5/19 (26%) birds. Some adverse effects were mitigated by adjusting dosing, and more severe adverse effects resolved after discontinuing haloperidol. This study provides descriptive data for a commonly used antipsychotic medication to assist veterinarians treating avian patients.
Identification of spp. From the Gastrointestinal Tract of Pet Parrots and Subsequent Antifungal Susceptibility Profiles
Lima da Rocha JH, Barbosa da Silva TI, Reckziegel GH, Lima de Oliveira TF, Zacarias Campelo MB and de Araújo Santos FG
Psittaciformes kept as pets can serve as reservoirs of various microorganisms, many of which have zoonotic potential, including spp. In this study, the antifungal susceptibility profiles of 16 spp. isolated from the oral and cloacal cavities of 20 pet parrots were evaluated. Samples from the animals' oral and cloacal cavities were obtained with swabs and stored in sterile tubes. For mycological isolation, samples were seeded on Mycosel agar medium at 30°C (86°F) for up to 5 days. The 16 isolates were seeded onto chromogenic medium to verify the species. For the antifungal susceptibility profiles, the samples were diluted in saline solution and plated on Sabouraud dextrose agar plates with antifungal discs. The species identified were (5/16, 31.2%), (4/16, 25%), (4/16, 25%), and (3/16, 18.8%). Twelve isolates were tested against 4 azole antifungals (miconazole, fluconazole, clotrimazole and ketoconazole). Approximately 58% (7/12) of spp. isolates showed intermediate susceptibility or resistance to the drugs used, with fluconazole being the least effective antifungal. These findings provide important information about the microbiota of wild birds raised as pets in Brazil and warn of the emergence of non- spp. resistant to azole antifungals widely used in human and veterinary medicine.
Mandibular Prognathism Correction in a Juvenile Umbrella Cockatoo () With the Use of an Orthosis
Magnotti J, Stahl SJ and Burrier K
A 9-week-old male umbrella cockatoo () presented with mandibular prognathism. The rostral rhinothecal tomial length appeared subjectively shorter than the rostral gnathothecal length, which was subjectively rostrally elongated. After an initial orthosis failed, a second orthosis was designed that employed the use of an orthopedic wire anchor in the rostral end of the rhinotheca, leaving the premaxillary bone undisturbed. Prior to placement of the anchor, skull radiographs were taken to measure the distance from the rostral tip of the rhinotheca to the rostral end of the premaxillary bone. This was done to mitigate iatrogenic trauma and prevent disruption of bone and underlying tissues when the orthopedic wire was deployed to anchor the rhinothecal tip. A hole was created in the rostral rhinotheca with a 20-gauge hypodermic needle rostral to the premaxillary bone. Orthopedic wire was placed through the hole and wrapped over the dorsal rhinotheca as an anchor. A second piece of orthopedic wire was formed into an elongated oval shape as a frame for the rhinothecal extension. Flexible, moldable plastic mesh was wrapped over the rhinotheca and orthopedic wire extension. Waterproof epoxy putty was placed over the rhinotheca and orthotic wires. The epoxy putty was replaced as needed until the rhinotheca had regrown into correct alignment. Twenty-five days post-placement, correct alignment was achieved, and the orthosis removed. The beak remained in correct alignment, and the bird developed normal use of the beak to engage in activities such as feeding, preening, and podomandibulation. Whereas methods for correcting mandibular prognathism have been described utilizing a variety of techniques and materials, there is a paucity of peer-reviewed literature on this procedure. This report describes the management and correction of this condition in a young bird as well as the involved anatomy, kinesiology, and details of this corrective procedure.
Spontaneous Wing Tip Edema in Captive Birds of Prey: Review of 41 Cases in the United Kingdom (2004-2022)
Byron-Chance D, Gomez L, Saraiva S, Hollwarth AJ, Esquivel E and George Dutton TA
There is limited literature regarding wing tip edema (WTE) in raptors, and much of our current understanding of the condition is based on anecdotal reports. The aims of this retrospective study were to describe the clinical features of WTE in birds of prey, to identify prognostic factors for return to flight and patient survival following diagnosis, and to develop and assess the clinical significance of a novel WTE grading system. Between 2004 and 2022, 41 cases of WTE were identified in 39 captive birds. No cases were found in wild birds. Harris's hawks (), lanner falcons (), and peregrine falcons () had the highest frequencies of WTE, and all cases presented between October and May. Increasing days of air frost per month and colder median monthly temperatures were significant risk factors for the development of WTE. Of the cases where patient outcomes were known, 23/31 (74.2%) cases returned to normal flight and 29/34 (85.3%) cases survived. End-stage disease, represented by primary flight feather loss and metacarpal ischemic (dry) gangrene, and enalapril use were associated with poor patient outcomes. Presentation within 24 hours of disease onset, isoxsuprine use, and physiotherapy were associated with improved patient outcomes. This study showed that WTE is an infrequently encountered but clinically significant condition in captive raptors and is associated with an overall high morbidity and moderate mortality risk.
Successful Neoadjuvant Chemotherapy and Surgical Removal of a Nonmetastatic Testicular Round Cell Tumor in a Solomon Island Eclectus Parrot ()
Baden R, Speer B, Garner M, Urraca VH and Fitzgerald B
An intracoelomic mass was palpated on an annual exam of a 24-year-old male Solomon Island eclectus parrot (). The initial diagnostic workup included a complete blood count, plasma biochemistry panel, and coelomic ultrasound. Computed tomography was highly suggestive of a testicular mass. Tamoxifen and the gonadotropin-releasing hormone agonists leuprolide and deslorelin were administered as neoadjunctive endocrine therapies. Biopsy and histologic examination confirmed a testicular mass consistent with a round cell tumor. Four doses of carboplatin 15 mg/kg IV were administered as neoadjunctive chemotherapy, and testicular size decreased by approximately 95%. The remaining gross tumor was removed via orchidectomy with clean but narrow margins. Seven months following surgery, a contrast CT scan did not show any evidence of recurrence of or metastasis from the original mass. This is the first report of successful treatment of a testicular tumor in a psittacine with neoadjuvant chemotherapy and orchidectomy.
Second-Generation Anticoagulant Rodenticide Toxicosis in a Wild Carnaby's Cockatoo ()
Le Souëf A, Lohr M, Vaughan-Higgins R, Wood K and Coiacetto F
A wild male Carnaby's cockatoo () was presented to a veterinary hospital after falling from a tree. The bird showed few clinical signs during the first days of hospitalization. On Day 4, the cockatoo showed excessive hemorrhage at a venipuncture site, epistaxis, and significant anemia (packed cell volume, 15%). The cockatoo was euthanized due to ongoing blood loss, weakness, and inappetence. Liver concentrations of brodifacoum (0.439 mg/kg wet weight) and difenacoum (0.033 mg/kg wet weight) had a total anticoagulant rodenticide concentration of 0.472 mg/kg wet weight and were above the threshold for toxicity for many avian species. To the authors' knowledge, this is the first time that anticoagulant rodenticide intoxication has been identified in a wild Australian psittacine species.
Uric Acid Ingluviolith in a Budgerigar ()
Wiggin P and Hoefer HL
This clinical report describes an adult, female budgerigar () diagnosed with an ingluviolith. The patient presented for intermittent regurgitation, and a palpable foreign body was present in the crop. Radiographs showed a radiopaque foreign body, and computed tomography showed an approximately 16 × 12 mm (length 3 width) structure in the crop with a soft tissue and focally mineralized center and a 2-3 mm-thick mineral-attenuating shell. An ingluviotomy was performed. The stone was first analyzed using polarized optical crystallography, a method that cannot analyze uric acid salts, and was incorrectly deemed a cystine calculus. The calculus was then analyzed using infrared spectroscopy and x-ray diffractometry and was confirmed to be a shell of subcrystalline to monoclinic crystals of anhydrous uric acid (CHNO) encrusting aggregates of numerous, threadlike, protein-based fibers. This case presents new information regarding avian ingluviolithiasis. The large size of the calculus indicates formation in the crop, and coprophagia linked to stress is thought to be the potential reason for urate and feather ingestion.
Molecular Detection of Infectious Bronchitis Virus in Captive-Bred Houbara Bustards ()
Al-Rasheed M
This article describes the first reported case of infectious bronchitis virus (IBV) in houbara bustards () from Saudi Arabia. Infectious bronchitis virus is a highly infectious virus that leads to major economic losses in the poultry industry. It is prevalent globally and causes severe respiratory and reproductive diseases in chickens. Although a wealth of information exists about IBV prevalence and transmission in domestic birds, similar information is lacking for houbara bustards. The major objectives of this research were to investigate whether IBV infections exist among houbara bustards at the National Wildlife Research Center in Taif, Saudi Arabia, and to determine the prevalence of this virus in this bird population. Fifty-eight oropharyngeal and cloacal swabs were gathered from 29 unvaccinated birds without clinical signs between 2017 and 2023. Extraction of complete RNA from the swab samples and reverse transcription-polymerase chain reaction testing were used to identify IBV. The prevalence of IBV in this population was 37.9% (11 of 29; 95% confidence interval, 20.2-55.5%), indicating transmission asymptomatically among captive houbara bustards. This research identified for the first time that houbara bustards were exposed to IBV, and that this exposure is not uncommon. To counter IBV in Saudi Arabia, recommendations include continuous monitoring of the virus, isolation of infected birds, phylogenetic analysis, genotypic identification of the virus in houbara bustard, and development of an effective vaccination.
Effective Dose of Dexmedetomidine with Nalbuphine Hydrochloride or Butorphanol Tartrate for Sedation in Buff Orpington Hens ()
Fithian J, Doden G and Brandão J
Chickens () are commonly used for research, food production, show, and companionship. Sedation is often necessary for sample collection, imaging, or treatment. Dexmedetomidine has been previously used to sedate birds, often with other sedatives. Butorphanol tartrate, a Schedule IV controlled substance, is commonly used but presents regulatory challenges. Nalbuphine hydrochloride, an opioid with similar receptor affinity to butorphanol, has potential as a noncontrolled alternative. Although information regarding nalbuphine use in birds is limited, its noncontrolled status makes it more accessible. The purpose of this study was to determine the effective dose to produce sedation in 50% (ED) of patients and to estimate the calculated effective dose of dexmedetomidine in combination with either butorphanol (DexBut) or nalbuphine (DexNal) in domestic hens to sedate 99% of patients (ED). Eighteen 33-week-old laying Buff Orpington hens were divided into 2 groups: one receiving DexBut (n = 9) and the second receiving DexNal (n = 9). Each hen was sedated with varying doses of intramuscular dexmedetomidine with a constant dose of either 2 mg/kg IM butorphanol or 12.5 mg/kg IM nalbuphine by an up-and-down design. Sedation was determined using a clinically applicable scoring system. The ED values of dexmedetomidine with 2 mg/kg IM of butorphanol, calculated by both the up-and-down method and logistic regression, were 38 and 49 µg/kg, respectively, while the ED values of dexmedetomidine in combination with 12.5 mg/kg IM of nalbuphine were 19 and 18 µg/kg, respectively. The estimated dexmedetomidine ED values with butorphanol or nalbuphine were 51 and 19 µg/kg, respectively. Multiple chickens in both groups exhibited open-mouth breathing and comb pallor but no lasting morbidity or mortality occurred. Combinations of DexBut or DexNal should be considered for sedation of domestic chickens.
Comparison of Manual Restraint With and Without Sedation on Outcomes for Wild Birds Undergoing Decontamination
Kelley CN, Kelly TR, Clatterbuck K, Knapp MC, Skoglund J and Duerr RS
The decontamination process for plumage-contaminated wild birds, such as those affected by oil spills, is lengthy and involves manual restraint and manipulation of all body parts. Birds commonly react to this in ways that suggest they are extremely stressed (eg, struggling, vocalizing). We proposed to reduce stress during the wash process using sedation and hypothesized that the use of sedation would not negatively impact survival. Contaminated birds in need of washing were randomly selected to be either sedated (butorphanol 2 mg/kg IM + midazolam 1 mg/kg IM and flumazenil 0.1 mg/kg IM for reversal) or not sedated at 3 US rehabilitation centers over the course of 1 year. Response to sedation was rated on a scale of 0-4 with 0 as no effect to 4 as excessively sedate. Data such as cloacal temperatures at various time points, lengths of various portions of the wash process, preening behavior in the drying pen, and disposition were collected. No statistical differences were found between sedated and nonsedated birds for any of the data points collected, including survival. There was a significant association between birds with higher cloacal temperatures in the drying pen and with birds held longer in the drying pen with improved survival; however, these findings were unrelated to whether the birds were sedated. Our findings show that sedation with butorphanol 2 mg/ kg IM and midazolam 1 mg/kg IM reversed with flumazenil 0.1 mg/kg IM can be used during the wash process for wild birds without adverse effects. Careful attention must be given to heat support for all birds while drying to prevent hypothermia.
Hearing Assessment of Free-Ranging Owls and Implications for Wildlife Rehabilitation: 31 Cases (2014-2023)
Trumpp KM, Mayer J, Roman CE and Kent M
Owls, members of the avian order Strigiformes, are nocturnal birds of prey that are found worldwide except for Antarctica. Traumatized, free-ranging owls are commonly presented to veterinary hospitals and wildlife rehabilitation facilities with the goal of providing medical care and rehabilitation to enable release back into their natural habitat. Minimal guidelines exist for the release of wildlife, and whereas a need for functional vision is described in raptors, assessing and evaluating hearing is usually not mentioned. This can be problematic for nocturnal predators because hearing is the primary sense utilized by owls when hunting and navigating in their dark environment. The brainstem auditory evoked response (BAER) test is a minimally invasive, objective assessment of hearing commonly used in companion animals. To the authors' knowledge, routine or standardized BAER evaluation has not been reported in traumatized, free-ranging owls. In the following retrospective study, 31 free-ranging owls presented to the University of Georgia Veterinary Teaching Hospital for known or suspected trauma or being found in a debilitated state underwent BAER testing to assess for the presence of complete sensorineural hearing loss. Similar to assessment of hearing in companion animals, the BAER test was elicited using a broad click stimulus delivered at 85 dB nHL. In all owls, qualitative assessment and peak latency measurements of the BAER test reflected hearing ability. This study highlights the importance of hearing in nocturnal raptors, how BAER testing can aid in decision making regarding rehabilitation, and provides a foundation for further investigation of hearing loss in traumatized owls. We suggest that veterinarians working with free-ranging owls in a rehabilitation setting should consider BAER testing as part of routine diagnostic testing.
Reference Interval Creation for Symmetric Dimethylarginine (SDMA) in Healthy Hispaniolan Amazon Parrots () and Quaker Parrots ()
Moreno AA, Tully TN, Liu CC and Heatley JJ
Renal disease is often identified as a cause of morbidity and mortality in avian patients. However, currently, early antemortem detection of renal disease in avian patients is difficult. Anatomical and physiological differences between mammals and birds mean the use of commonly employed diagnostic testing (ie, measurement of blood urea nitrogen [BUN] and serum creatinine, urinalysis, and ultrasonography) are either nondiagnostic or difficult to achieve. Symmetric dimethylarginine (SDMA) is considered a more sensitive marker for renal disease in humans, dogs, and cats. However, SDMA has not yet been assessed for diagnostic use in any psittacine species. In this study, we establish reference ranges for SDMA in both Hispaniolan Amazon parrots (, HAP) and Quaker parrots (, QP). Blood was collected from 23 Amazon parrots and 32 Quaker parrots maintained in research facilities. Measurement of SDMA through a commercially available immunoassay (IA-SDMA) as well as creatinine, BUN, uric acid, phosphorus, calcium, sodium, potassium, and chloride were determined through IDEXX Laboratories. Plasma SDMA concentrations ranged from 6 to 15 µg/dL and 3 to 15 µg/dL for the HAP and QP, respectively. Sex was a confounding factor for the QP population, but sex did not have a significant effect on SDMA for the HAP population. No significant correlations were identified between SDMA concentrations and other parameters in either psittacine species. Our results show proof of concept for the IA-SDMA and provide reference intervals for SDMA in HAP and QP. Further investigation is required to determine the validity of this assay and the predictive power of SDMA in the detection of renal impairment for parrots and other common companion birds.
Plasma and Tissue Amikacin Concentrations Following Regional Limb Perfusion of Chickens ()
Ratliff C, Clarke L, Knych HK, Morello SL and Mans C
Intravenous regional limb perfusion (IVRLP) has been used in the treatment of pododermatitis and distal limb infections, which are significant causes of morbidity in avian species. This intravenous drug administration technique is designed to achieve high drug tissue concentrations while minimizing systemic toxic effects. Amikacin is commonly used for IVRLP in veterinary medicine, but dosing guidelines have not been established for its use in birds. The current study aimed to determine the tissue concentration of amikacin after a single IVRLP administration in healthy, euhydrated leghorn hen chickens (). Chickens received a single IVRLP dose of 10 mg/kg amikacin and were euthanatized posttreatment at 1 hour (n = 6), 12 hours (n = 6), and 24 hours (n = 6) to assess tissue and synovial fluid concentrations of amikacin in the injected leg. Mean tissue concentrations were highest 1 hour post-IVRLP (synovial fluid = 153.0 µg/mL, metatarsal pad tissue = 26.05 µg/mL) before declining at the 12- and 24-hour time points. This indicates that administration of amikacin via IVRLP can reach minimum inhibitory concentrations of common bacterial isolates in tissues after a single treatment with 10 mg/kg amikacin. Regional limb perfusion every 24 hours is recommended, although the minimum days of treatment may be case dependent and vary based on response to therapy.
Pharmacokinetics of Trazodone in Hispaniolan Parrots ()
Straub HM, Tully TN, Dirikolu L, Lehner AF, Zyskowski J and Buchweitz J
The objective of this study was to establish the pharmacokinetics of a single oral dose of trazodone in the Hispaniolan Amazon parrot (). Trazodone is a selective serotonin antagonist and reuptake inhibitor used commonly in both human and veterinary medicine as an antidepressant behavioral modification medicine. A single oral dose of compounded trazodone hydrochloride solution (20 mg/mL) at 50 mg/kg was administered to a total of 7 healthy adult Hispaniolan Amazon parrots. The 7 healthy adult parrots ranged in age from 10 to 15 years and weighed 228 to 323g. Blood was collected at baseline (2 weeks before study) and at 1, 2, 4, 6, 10, and 14 hours post-drug administration. Plasma concentrations of both trazodone and its active metabolite m-chlorophenylpiperazine (mCPP) were measured via liquid chromatography tandem mass spectrometry. Noncompartmental pharmacokinetic analysis was completed. The half-life (t) ± SD of trazodone for the Hispaniolan parrots was 1.89 ± 0.49 hours, and the t ± SD of mCPP metabolite was 1.9 ± 0.55 hours. Maximum serum drug concentrations, or C (ng/mL), were 738.3 ± 285.3 for trazodone. Times to achieve C (hours) for trazadone and the mCPP metabolite were 1 hour and 2 hours postdosing, respectively. While this study did not establish the behavioral effects of trazodone, no adverse side effects were observed throughout the 48-hour period following drug administration and blood collection. Our results indicate that the oral administration of a 50-mg/kg single dose of trazodone to Hispaniolan parrots may be considered a safe dose. Plasma concentrations are comparable to previously published values in humans, dogs, horses, and pigeons () for up to 14 hours following dosing. This study indicates that further studies are needed to establish the pharmacodynamics and the efficacy of trazodone in the medical management of behavioral problems in psittacine species.
Prevalence, Anatomical Distribution, and Risk Factors of Adipocytic Tumors and Xanthomas in Psittaciformes: 1096 Cases (1998-2018)
Megan L, Guzman DS, Keel K and Beaufrère H
Adipocytic tumors are mesenchymal tumors that are commonly reported in psittacine birds; however, large-scale studies evaluating their prevalence and associated risk factors are lacking. A retrospective study of adipocytic tumors in psittacine birds was performed by reviewing pathology submissions from the University of California, Davis-Drury Reavill Pathology Database, containing 26 013 submissions from psittacine birds (1998-2018). Age, sex, genus, anatomic distribution, and pathological diagnosis were collected for each case when available. The prevalence, risk factors, and association with other lipid-accumulation disorders were reported. A total of 450 cases of lipoma, 129 cases of myelolipoma, 35 cases of hemangiolipoma, 31 cases of liposarcoma, and 451 cases of xanthoma were identified. The prevalence of adipocytic tumors and xanthomas on necropsy was 1.3% (158/11 737, 95% confidence interval [CI]: 1.1-1.6). Adipocytic tumors were identified in 27 genera. (odds ratio [OR] = 1.93, 95% CI: 1.24-2.99, = 0.004), (OR = 2.3, 95% CI: 1.0-5.2, = 0.041), (OR = 3.4, 95% CI: 2.1-5.5, < 0.001), and (OR = 3.5, 95% CI: 2.0-6.1, < 0.001) had significantly higher odds of developing adipocytic tumors compared with other genera, whereas had significantly lower odds (OR = 0.5, 95% CI: 0.3-0.9, = 0.030). Age was also a significant risk factor for many types of adipocytic tumors. There was no significant association between general adipocytic tumor formation and atherosclerosis or hepatic lipidosis. Xanthomas were associated with atherosclerosis (OR = 1.88, 95% CI: 1.01-3.51, = 0.048), but not hepatic lipidosis ( = 0.503). On necropsy, the trunk and air sacs were the most common sites of xanthoma formation, whereas the trunk and liver were the most common sites of lipoma and myelolipoma formation, respectively.
Avian Diabetes Mellitus: A Review
Van de Weyer Y and Tahas SA
Diabetes mellitus (DM) is an uncommon, poorly documented metabolic disorder of birds. Extrapolating knowledge from DM in mammals is challenging because of marked differences in avian physiology and metabolism. A literature review from December 1991 to January 2022 identified 14 publications covering 16 diabetic birds, 63% (10/16) of which belonged to the order Psittaciformes with as the predominant genus. No sex predilection was noted, but males generally presented at a younger age. Commonly reported clinical signs included polyuria 94% (15/16), polydipsia 88% (14/16), weight loss 75% (12/16), lethargy 63% (10/16), and polyphagia 38% (6/16). Diagnosis of DM was based on the presence of clinical signs and persistent hyperglycemia 100% (16/16), often with glucosuria 93% (13/14), response to insulin therapy 80% (8/10), and pancreatic pathology 90% (9/10). Specific treatment for DM was initiated in 14 patients, but blood glucose regulation for 6 months or longer was only achieved in 6 birds. Five of the regulated birds were managed with injectable long-acting insulin and 1 with oral glipizide combined with dietary modifications. However, glipizide yielded poor results in other cases, likely attributable to a lack of functional beta cells. Three diabetic birds progressed to remission. Treatment proved unsuccessful for 7 patients with a mean survival time of 36 days from diagnosis. One patient was lost to follow-up, and 2 were euthanized immediately following diagnosis. Histological examination of the pancreas frequently (90%, 9/10) revealed abnormalities including atrophy, fibrosis, and vacuolization of the endocrine islets with or without lymphoplasmacytic pancreatitis. Comorbidities, including hemosiderosis and infection, were common. This review suggests that birds diagnosed with DM are primarily affected by a type I diabetes as observed in dogs and humans. In contrast to mammalian species, avian DM is often associated with underlying disease and a complete clinical workup is essential to diagnose and address secondary disease conditions prior to initiating long-term insulin therapy.
Surgical Repair of Psittacine Femorotibial Luxation: A Case Series
Simonis KM, Cowan ML, Williams L and Baron HR
Luxation of the psittacine femorotibial joint most commonly occurs following trauma or as a development abnormality. Historically, this injury is considered to have a poor prognosis in birds; however, surgical management may result in acceptable and functional outcomes. This case series describes the surgical techniques, complications, and outcomes of 7 cases of femorotibial luxation in psittacine birds. Of the 7 cases, 6 were chronic injuries. Surgical repair methods included conjoined intramedullary pinning, transarticular pinning with an external skeletal fixator (ESF), a combination of extracapsular stabilization and ESF, ESF alone, and a combination of conjoined intramedullary pins with an ESF. An acceptable outcome was achieved in 75% (6/8) of luxated femorotibial joints managed with surgical methods. All cases were female birds of various species, suggesting a possible sex predisposition for stifle luxation.
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