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An adult male green-winged (Ara chloropterus) × military (Ara militaris) hybrid macaw of unknown age was presented to the Texas A&M Veterinary Medical Teaching Hospital for evaluation of left periocular swelling, blepharospasm, and ocular discharge. Complete ophthalmic examination and B mode ocular ultrasonography were performed to evaluate the affected eye. Ocular examination revealed a blind left globe with exophthalmos, periocular swelling, diffuse corneal edema, and severe anterior fibrinous uveitis obscuring visualization of the intraocular structures. An ultrasound examination revealed a hyperechoic mass that filled the posterior segment of the globe. Focal discontinuity of the posterior sclera suggested scleral rupture. Enucleation with histopathology was recommended and performed 1.5 months later. Intraoperatively, a heavily pigmented and friable soft tissue mass extruded through the posterior sclera and extended into the orbit. Histologically, the mass was consistent with a malignant melanoma. The patient died 18 hours after the surgical procedure because of unknown complications. Postmortem examination did not identify evidence of metastasis. This study described the clinical appearance and histopathologic findings of a rare ocular neoplasm with extrascleral extension in a hybrid macaw. Although uncommon in psittacine birds, primary ocular melanocytic neoplasms may display features of malignancy with scleral or orbital invasion, or both.

Gastrointestinal disease is a common clinical problem in captive cheetahs (Acinonyx jubatus). It is reported that gastritis affects the vast majority of the captive population of cheetahs. Pancreatitis and acute and chronic enteritis have also been reported. These issues pose significant long-term health and welfare implications for cheetahs. Cobalamin, folate, methylmalonic acid (MMA), gastrin, feline pancreatic-specific lipase immunoreactivity (fPLI), and feline trypsin-like immunoreactivity (fTLI) immunoassays are important biomarkers of gastrointestinal disease in domestic cats. The goal of this study was to determine if these immunoassays validated in domestic cats could be used clinically in cheetahs, by establishing reference intervals (RI) for these biomarkers in cheetahs. A cohort of 40 clinically healthy cheetahs was selected from three zoological institutions on the basis of being free of clinical gastrointestinal disease and extra-gastrointestinal disease that could affect biomarkers, as well as having banked frozen serum. Cheetah biomarker RI, with domestic cat RI for comparison in parentheses, are as follows: cobalamin 470–618 pg/ml (290–1500 pg/ml), folate 2.2–15.7 ng/ml (9.7–21.6 ng/ml), MMA 365–450 nM/L (139–897 nM/L), fPLI 0.5–1.2 µg/L (0–4 µg/L), and gastrin 30–50 pg/ml (

CASE DESCRIPTION A 1-year-old male eclectus parrot (Eclectus roratus) with a 3- to 4-month history of blepharospasm in the right eye was referred to a veterinary medical teaching hospital for further evaluation. Conventional medical treatments had been ineffective. The referring avian specialist had plucked a suspected ectopic feather from the right eye 6 weeks prior to the referral evaluation. CLINICAL FINDINGS The parrot was sedated, and ophthalmic examination of the right eye with slit-lamp biomicroscopy revealed a 3 × 2 × 2-mm raised vascular mass with a focally pigmented center associated with the temporal aspect of the leading edge of the third eyelid. No abnormalities were detected in the left eye. TREATMENT AND OUTCOME The parrot was anesthetized, and the right eye mass was excised and submitted for histologic examination. Histologically, there was a single pigmented feather follicle bulb surrounded by multiple discrete lymphoid follicles and moderate lymphoplasmacytic inflammation within the substantia propria of the third eyelid conjunctiva. The histologically normal feather follicle in an abnormal location classified the lesion as a choristoma. Nine months after surgery, the parrot had no signs of ocular discomfort and no overt regrowth of the feather follicle. CLINICAL RELEVANCE For the eclectus parrot of this report, a lesion caused by normal differentiation of an ectopic feather follicle in the right third eyelid was successfully treated. A third eyelid choristoma appears to be a hitherto unreported pathological finding in avian species. Although rare, the presence of a choristoma should be considered as a differential diagnosis for birds with blepharospasm.

A northern crested caracara (Caracara cheriway) was presented after being found nonambulatory in a field. On physical examination, the bird had severe hind-limb paresis. The bird did not improve after 10 days of hospitalization and was euthanized. Histologic examination of the cerebrum and spinal cord revealed multiple adult filarial nematodes surrounded by granulomatous inflammation with several multinucleated giant cells. These parasites were confirmed to be Chandlerella quiscali with polymerase chain reaction. This is the first report of C. quiscali in a bird of prey.

Objective To obtain normative ocular data for Japanese quail as they mature from juveniles to adults. Animals studied Twenty-six captive Japanese quail comprising thirteen males and thirteen females, free of ocular disease, were included in the study. Procedures Ophthalmic reference values were measured in both eyes at 1 and 5 months of age. A complete ophthalmic examination was performed, including neuro-ophthalmic reflexes, slit lamp biomicroscopy, phenol red thread test (PRTT), rebound tonometry, fluorescein staining, horizontal corneal diameter measurement, indirect ophthalmoscopy, and ocular ultrasound biometry. Ultrasound biomicroscopy measurements of axial globe length, lens thickness, vitreal chamber length, and pecten length were recorded. The depth of the anterior chamber was calculated by subtracting the lens thickness and vitreous length from the axial globe length. Measures of association and descriptive statistics were analyzed using STATA-14 and STATA-15. Results Juvenile and adult females were heavier than age-matched males. Weight, intraocular pressure, horizontal corneal diameter, axial globe length, and lens thickness measurements increased with age. No statistically significant differences were found in the remainder of measurements among individuals in different sex or age-groups. Conclusions This work provides reference values and clinical findings that can be used in future research on quail and ocular disease.

Lymphoplasmacytic inflammation associated with bornavirus N protein occurs in the epicardial ganglia, myocardium and endocardium of birds diagnosed with proventricular dilatation disease (PDD). These pathological findings suggest that sudden death in psittacine birds might stem from cardiac compromise due to parrot bornavirus (PaBV) infection. Therefore, we investigated cardiac lesions in cases of PDD, searching databases from 1988 to 2019, and reviewed three experimental studies of PaBV infection. Fifty cases of PDD in birds infected naturally with PaBV and 27 cases of PDD in birds infected experimentally with PaBV (all having descriptions of inflammatory cardiac lesions) were reviewed. For each case, five regions of the heart were evaluated by light microscopy and immunohistochemistry (IHC). These regions were the epicardial ganglia/nerves, the endocardium, the myocardium, the Purkinje fibres and the great vessels. Sudden death was documented in 17/50 naturally infected cases, while 23/50 had digestive signs, and only 12/50 had neurological signs. Grossly, only five naturally-infected and five experimentally-infected cases had cardiomegaly or hydropericardium. Epicardial ganglioneuritis was the most consistent microscopical finding in natural (46/50) and experimental cases (26/27), followed by myocarditis (34/50) for naturally-infected and endocarditis for experimentally-infected birds (6/27). PaBV-2 antigen was detected most frequently by IHC in the epicardial ganglia (54/77) compared with the other tissues. This retrospective study demonstrates the presence of PaBV protein and inflammation in the heart of birds infected with PaBV and suggests a link between PaBV and cardiac disease and sudden death in psittacine birds.

This report describes the clinical, macroscopic, histopathological and immunohistochemical features of a spontaneous multicentric extraskeletal sarcoma in an adult male African hedgehog (Atelerix albiventris). It also provides a succinct up-to-date review on neoplasia in this species. On autopsy examination, main gross findings included a moderately demarcated cranial mass and a multilobulated, caudal intra-abdominal mass. The cranial mass had perforated the underlying temporal and occipital bones and had extended into the cranial vault and was compressing the surface of the cerebellum and cerebrum. Histologic, histochemical and immunohistochemical analyses supported a diagnosis of multicentric poorly differentiated spindle cell sarcoma with fibrosarcomatous, storiform and myxoid foci. The high incidence of neoplasia and cross similarities renders the African hedgehog a suitable species for comparative pathology studies.

Based on necropsy review, neoplasia in reptiles has a comparable frequency to that of mammals and birds. Reptile neoplasia is now more frequently diagnosed in clinical practice based on increased use of advanced diagnostic techniques and improvements in reptilian husbandry allowing greater longevity of these species. This article reviews the current literature on neoplasia in reptiles, and focuses on advanced diagnostics and therapeutic options for reptilian patientssuffering neoplastic disease. Although most applied clinical reptile oncology is translated from dog and cat oncology, considerations specific to reptilian patients commonly encountered in clinical practice (turtles, tortoises, snakes, and lizards) are presented.

A 2-year-old castrated male Eastern fox squirrel ( Sciurus niger ) presented with a 3- to 4-week history of stranguria and intermittent lower urinary tract obstruction. A complete blood count, serum chemistry analysis, urinalysis, urine culture, radiographic imaging, and ultrasonography helped formulate a diagnosis of severe, chronic cystitis-induced lower urinary tract obstruction. The patient was treated using a pigtail drainage catheter followed by scrotal urethrostomy and abdominal exploratory surgery. Lower urinary tract disease and obstruction can occur sporadically in rodent species, resulting in presentation for hematuria, stranguria, decreased appetite, and lethargy. When complete obstruction occurs, urinary catheterization and/or surgical intervention are warranted. This case report demonstrates the use of scrotal urethrostomy for treatment of complicated lower urinary tract obstruction in a rodent species.

Blood biochemical values are useful as indicators of disease in veterinary practice and for health assessments of free-ranging animal populations. We analyzed blood biochemical values for free-living nestling and adult scarlet macaws ( Ara macao macao) in southeastern Peru with an Abaxis VetScan VS2 portable analyzer with Avian/Reptilian Profile Plus rotors. The resulting data were used to create provisional age-independent reference intervals for this instrument for wild scarlet macaw nestlings, calculate blood biochemical ranges for this instrument for wild adults, and examine age-related trends in nestlings. Levels of 11 parameters were studied: albumin, aspartate aminotransferase, calcium, creatine kinase, globulin, glucose, phosphorus, potassium, total protein, sodium, and uric acid. Bile acid levels were generally below the instrument detection level and were not evaluated. Most values and their trends with bird age were comparable to those observed in captive large macaw nestlings. Albumin, aspartate aminotransferase, globulin, glucose, total protein, sodium, and uric acid levels increased with nestling age to adulthood. Creatine kinase, phosphorus, and potassium concentrations decreased with age to adulthood. Calcium concentrations did not change between nestlings and adults. These changes in values with age are broadly in agreement with values in other avian species and likely reflect physiologic and developmental changes as nestlings mature.

Wobbly hedgehog syndrome (WHS) is a leading cause of neurologic disease in African pygmy hedgehogs (APHs; Atelerix albiventris). This study describes the signalment, clinical signs, gross, microscopic, and ultrastructural lesions of WHS in a cohort of 12 pet APHs. Microscopically, lesions consisted of status spongiosus of the white matter, typically bilateral and symmetrical, with myelin degeneration and loss that was accompanied by neuronal/axonal degeneration plus reactive microgliosis and mild, focal astrocytosis and astrogliosis. Lesions were most severe in the cerebellum and medulla oblongata, as well as cervical and thoracic spinal cord. Less affected areas were the corona radiata, corpus callosum, corpus striatum, internal capsule, and the mesencephalon. Ultrastructurally, the lesions consisted of splitting of the myelin sheath at the intraperiod line with subsequent focal expansion, resulting in status spongiosus, disruption, dilatation, rhexis, and phagocytosis. Based on these results, WHS is best described as a “spongy myelinopathy” with widespread central nervous system involvement.

Summary A 17-year-old female emu (Dromaius novaehollandiae) was presented for clinical evaluation due to a 3-week history of anorexia and progressive weight loss. The emu died after sedation. At necropsy examination, the ovary and the majority of the oviduct were effaced by a multinodular cystic mass and accompanied by 6 l of coelomic effusion. Histopathology revealed a neoplasm composed of well-differentiated, poorly organized tissues derived from ectoderm, mesoderm and endoderm. Tissues within the neoplasm expressed glial fibrillary acidic protein, desmin and cytokeratins AE1/AE3, respectively, confirming the diagnosis of teratocarcinoma.

To evaluate potential factors related to avian atherosclerosis, plasma cholesterol and triglyceride values were measured in 35 apparently healthy captive monk parakeets (Myiopsitta monachus). Birds were categorized as healthy or at risk based on body condition score and weight and were also evaluated based on their aviary environmental conditions. Plasma cholesterol mean was 8.008mmol/L (range: 4.655 to 20.33mmol/L) or 309.65mg/dl (range: 180 to 786mg/dl) for all birds sampled. Plasma triglyceride mean for all birds sampled was 4.364mmol/L (range: 0.960 to 44.62mmol/L) or 386.54mg/dl (range: 85 to 3952mg/dl). Thirty plasma samples were evaluated through density gradient ultracentrifugation lipid profiling techniques used to examine risk of cardiovascular disease in humans. The resultant lipid density profile graph was determined from the hydrated densities of the following lipids: triglyceride-rich lipoproteins, low-density lipoproteins (LDL) and subfractions, and high-density lipoproteins and subfractions. When analyzed using linear discriminant analysis, lipid profiles of triglyceride-rich lipoproteins, LDL1, LDL2, and high-density lipoprotein 2b subfractions were increased ( P

Computed tomography (CT) is an increasingly available and valuable imaging modality for the diagnosis of companion avian pets. Previously, CT studies of birds required general anesthesia with inhalant anesthetics. Owing to the risks associated with general anesthesia, the authors of this article investigated the effect of sedation on birds during a CT examination. In this study, 10 psittacine birds were imaged using a 40-slice helical CT scanner. Birds were sedated with midazolam and butorphanol and placed in a positioning device. Following the initial study, birds were removed from the device and placed under general anesthesia with isoflurane. A second study was then performed. Two radiologists, blinded to the identity of the birds and partially blinded to the conditions of the study, reviewed the images. Studies were evaluated using a questionnaire consisting of 18 questions. Each question was scored on a Likert scale. A Wilcoxon signed rank test compared scores of sedated and anesthetized birds. A significant difference ( P = 0.05) between sedated and anesthetized studies was found for 2 of 18 (11.1%) questions for radiologist 1 and 1 of 18 (5.5%) questions for radiologist 2, with differences identified in the scleral ossicles and the femoral heads. Interrater agreement for all questions using a linearly weighted κ was 0.334 and 0.311 for sedated and anesthetized birds, respectively, indicating fair agreement. The interrater agreement, excluding the head and musculoskeletal system, was 0.381 for sedated animals, indicating fair agreement, and 0.404 for anesthetized birds, indicating moderate agreement. Based on our results, performing CT studies in birds with sedation is a viable alternative to studies performed under general anesthesia.

This study was designed to investigate the effectiveness of meloxicam in the treatment of proventricular dilatation disease induced by challenge with avian bornavirus (ABV), strain M24. Three groups of 4 cockatiels were employed. Group 1 was challenged with ABV alone, group 2 was challenged with ABV and 20 days later began daily oral meloxicam treatment, and group 3 received daily oral meloxicam alone. All birds in groups 1 and 3 remained in apparent good health and maintained their weight until being euthanized on day 150 after challenge (group 1) or day 130 of treatment (group 3). In contrast, group 2 birds died or were euthanized on or before day 98 because of severe weight loss and depression. Necropsy and histopathology results indicated that all birds in group 2 had pathologic evidence of proventricular dilatation disease. ABV was detected by reverse transcriptase polymerase chain reaction testing in all the major organs of the group 2 birds. The proventriculus was enlarged in 2 birds in group 1, and 75% of the birds in this group had ABV detectable in all their major organs. No significant lesions were observed in group 3 birds.

Acquired dental disease and the formation of elodontomas are often diagnosed in sciurids. The formation of the elodontoma may be preceded by a traumatic tooth injury or other initiating factors. The degree of disease severity varies based on individual presentation and the time of detection. Maxillary elodontomas in sciurid species cause airway obstruction that can prove fatal for these obligate nasal-breathing animals. A thorough understanding of rodent dental anatomy and a complete diagnostic workup are required for diagnosis, prognosis, and surgical planning of elodontoma presentations. This article highlights 2 successful surgical techniques for the removal of the maxillary incisors in sciurid patients with almost total occlusion of the nasal passage.

Avian bornavirus (ABV) is a neurotropic virus that can cause gastrointestinal and/or neurologic signs of disease in birds. The disease process is called proventricular dilatation disease (PDD). The characteristic lesions observed in birds include encephalitis and gross dilatation of the proventriculus. ABV is widely distributed in captive and wild bird populations. Most birds infected do not show clinical signs of disease. This article is an update of the Veterinary Clinics of North America article from 2013: Avian Bornavirus and Proventricular Dilatation Disease: Diagnostics, Pathology, Prevalence, and Control.

Based on necropsy review, neoplasia in reptiles has a comparable frequency to that of mammals and birds. Reptile neoplasia is now more frequently diagnosed in clinical practice based on increased use of advanced diagnostic techniques and improvements in reptilian husbandry allowing greater longevity of these species. This article reviews the current literature on neoplasia in reptiles, and focuses on advanced diagnostics and therapeutic options for reptilian patientssuffering neoplastic disease. Although most applied clinical reptile oncology is translated from dog and cat oncology, considerations specific to reptilian patients commonly encountered in clinical practice (turtles, tortoises, snakes, and lizards) are presented.

Psittacine birds are challenging laboratory subjects, as they are typically long-lived, very social, highly intelligent, and easily stressed. The benefits of positive reinforcement techniques in animal management have been well documented for mammalian species; however, there are few publications on such programs for birds. To demonstrate the practicality of positive reinforcement training of laboratory birds to cooperate with research procedures involving direct manipulation of individuals, 9 adult macaws (Ara species; 5 individuals and 2 pairs) were trained in 10-minute sessions, twice a day for 8 weeks. The trained behaviors were: target, stay, accept liquids from a syringe, step onto a perch, step onto a scale, allow pressing a syringe to the pectoral area (surrogate for an intramuscular injection), and step onto a towel. All individually housed birds reliably targeted, stayed, and accepted a syringe, and 4 of the 5 stepped onto a perch. One bird performed all of the behaviors. Paired birds learned advanced techniques significantly faster when trained by 2 trainers versus 1 trainer. All behaviors that were mastered during the initial phase of training were successfully transferred so that the birds would reliably perform for the husbandry staff. We conclude that positive reinforcement techniques provide an effective, practical way to train laboratory macaws in behaviors useful for veterinary practice and research. Positive reinforcement used to evoke voluntary participation in procedures will help reduce stress associated with capture and restraint and improve welfare for laboratory parrots.

An approximately 30-year-old male spectacled Amazon parrot (Amazona albifrons) was presented with a 2-week history of ataxia, head shaking, weight loss and seizures. Gross findings on necropsy examination included atrophy of the musculature, ruffled feathers and minimal epicardial and abdominal fat. Microscopically, there were perivascular cuffs of macrophages with fewer lymphocytes in the grey and white matter of the brain and spinal cord. These lesions were accompanied by gliosis and mild vacuolation of the white matter. In the small intestine, up to 70% of the intestinal ganglia were effaced by infiltrates of macrophages and fewer lymphocytes. The intestinal lamina propria contained multiple inflammatory aggregates of a similar nature. Ziehl-Neelsen staining revealed the presence of numerous bacilli within the cytoplasm of macrophages in the central nervous system (CNS) and enteric ganglia. Amplification of the DNAJ gene confirmed a mycobacterial infection and subsequent polymerase chain reaction (PCR) using a species-specific primer confirmed the aetiology as Mycobacterium genavense. Infection of the CNS with Mycobacterium spp. is uncommon and has not been previously reported in a parrot. This case is unusual in that the organism exhibited tropism for neural tissue.

The gastrointestinal microbiota plays a fundamental role in health and disease. Only limited data are available about the composition of the intestinal microbiota of captive animals compared to those of wild animals. The aim of the present study was to characterize the cloacal microbiota of apparently healthy wild and captive parrots. A total of 16 parrots, 8 wild and 8 captive, belonging to 3 different species, were used in this study. Cloacal material was collected via cloacal swabbing. DNA was extracted and 16S rRNA genes were amplified using universal bacterial primers. Constructed 16S rRNA gene clone libraries were compared between groups. A total of 518 clones were analyzed, and 49 operational taxonomic units (OTUs) were identified. The OTUs were classified in 4 bacterial phyla: Firmicutes (72.9%), Proteobacteria (14.9%), Actinobateria (12%), and Bacteroidetes (0.2%). Bacterial diversity was significantly lower in wild birds than in captive birds. Principal component analysis based on the Unifrac distance metric indicated that the cloacal microbiota differed between wild and captive parrots. Staphylococcus saprophyticus was significantly more abundant in wild birds, while Escherichia coli was significantly more abundant in captive birds. In conclusion, wild and captive parrots appear to have differences in the composition of their cloacal bacterial microbiota. The clinical significance of these differences remains to be determined.

Parrots are amazing creatures. They are beautiful, intelligent, and entertaining. Many psittacine species have the ability to mimic speech and sound, thereby making them a desirable animal to own. People may obtain parrots, believing they are easy to care for because they live in a relatively small cage. In reality, these birds are loud, messy, destructive, live long lives, and need a great deal of attention. On occasion, new parrot owners quickly realize that a bird is not a good choice for a pet. This buyer regret may lead the bird owner to sell or give the bird away; consequently, these parrots may end up in the care of rescue or sanctuary organizations. This article discusses the advantages and disadvantages of rescue and sanctuary organizations and the need to establish guidelines for the welfare of parrots maintained at these facilities.

Ferrets are an increasingly popular pet in the United States. They are active, gregarious pets that delight their owners with playful antics. One of the issues that ferret owners and veterinarians have had to deal with is their shortened life span. Although literature cites the life span of the ferret as 8 to 10 years, most veterinarians see ferrets as "old" at as early as 3 years of age. Most information on senior ferrets has focused on neoplastic diseases. This article discusses husbandry and nutritional issues of the aging ferret, more commonly seen geriatric diseases, and diagnostic and treatment options.

For biochemical analysis with a point-of-care biochemical analyzer, standard procedure is to analyze the sample as rapidly as possible (

Fentanyl is a mu opioid agonist with 80–100 times the analgesic potency of morphine. Fentanyl is used in several mammalian species for relief of severe pain, but its use has not been investigated in psittacine birds. To determine the pharmacologic disposition of fentanyl in healthy white cockatoos (Cacatua alba), we measured fentanyl plasma concentrations in sequentially collected samples after administration of fentanyl at 0.01 or 0.02 mg/kg IM. To investigate the analgesic effects of fentanyl in conscious cockatoos, we compared the change in pre- and posttreatment levels of electrical and thermal noxious stimuli necessary to elicit a withdrawal response in birds administered fentanyl at 2 different doses (0.02 mg/kg IM or 0.2 mg/kg SC) and those given saline. Fentanyl was rapidly absorbed and plasma concentrations declined with an elimination half-life of 1.2–1.4 hours. Plasma concentrations considered to be analgesic in humans were maintained for at least 2 hours with the 0.02 mg/kg dose. Howe...

Mycotic keratitis is most commonly reported in horses and humans and is rarely reported in birds. We diagnosed mycotic keratitis, localized to the left eye, in an adult blue-fronted Amazon parrot (Amazona aestiva). The ophthalmic examination revealed a diffuse yellow-green haze encompassing the entire surface of the left cornea. Diffuse fluorescein uptake occurred in the entire cornea. The right eye appeared normal. Aspergillus fumigatus was isolated on conjunctival culture. The affected eye was enucleated because of the bird's discomfort and the poor prognosis for successful treatment. Histopathologic examination revealed a severe granulomatous keratitis with intracorneal fungal hyphae and corneal perforation. Multinucleated giant cells and fungal hyphae were present within the anterior chamber. Aspergillus fumigatus is an uncommon cause of keratitis in birds but should be considered as a potential cause of refractory ulcers.

Objectives To describe characteristics of echocardiography and cranial coelomic radiography in a cohort of iguanas. Animals Twenty apparently healthy adult green iguanas (Iguana iguana) from a reptile sanctuary. Methods Physical examination, radiography, two-dimensional and color Doppler echocardiography were performed to assess cardiac structures and function, and any related normal or abnormal findings were recorded. Results Echocardiographic examination was possible without sedation and allowed visualization of the great vessels, atria, and ventricle. Some structures could not be evaluated in a minority of the iguanas due to individual differences in bony conformation and imaging quality. Suspected abnormal echocardiographic findings in 3 iguanas included pericardial effusion (n = 1) and enlarged caudal vena cava and/or sinus venosus (n = 2). Objective measurements were repeatable as assessed by within-subject coefficient of variation, and reliable as assessed by intra-observer intraclass correlation coefficient. Left atrial and ventricular measurements were significantly correlated with body weight. Valve regurgitation was common, with atrioventricular valve regurgitation present in 53% (9/17) and aortic or pulmonic valve regurgitation in 71% (12/17) of otherwise normal iguanas. A heart murmur was not appreciated during examination of any of the iguanas. Heart size cannot be measured radiographically due to superimposition and silhouetting of other coelomic structures. Echocardiographic or radiographic findings consistent with mineralization of the great vessels were present in 76% of iguanas (13/17). Conclusions Echocardiography in iguanas is well tolerated without sedation and allowed both subjective evaluation and structural measurements. Valve regurgitation and great vessel mineralization were commonly observed in this cohort of apparently healthy adult iguanas.

Avian bornavirus (ABV) is a known cause of proventricular dilatation disease in parrots and encephalitis in waterfowl and is a significant cause of both morbidity and mortality in captive birds. Transmission is thought to occur primarily by the fecal-oral route. In an aviary setting, controlling the disease involves a thorough understanding of the complete transmission cycle, including determining whether vertical transmission occurs. In this study, vertical transmission of ABV was evaluated by using 61 eggs obtained from birds in 2 aviaries where proventricular dilatation disease was prevalent, and the presence of ABV had been confirmed by fecal reverse transcription-polymerase chain reaction by using a primer set designed to detect ABV M protein. The contents of these eggs were then tested for the presence of ABV RNA. Of the eggs tested, 10 were determined to contain ABV RNA. These eggs ranged from apparently nonviable to those that contained developing embryos. ABV was detected in the brain tissue of 2 embryos. It remains to be proven that infected chicks can hatch from these eggs to complete the vertical transmission cycle; however, these findings suggest that vertical transmission of ABV may occur.

An isolate of genotype 2 avian bornavirus (ABV) was recovered from a cockatiel (Nymphicus hollandicus) that was euthanatized for an unrelated lesion and showing no clinical evidence of proventricular dilatation disease (PDD). On histopathologic examination, mild inflammatory lesions were present in the heart and brain, but gastrointestinal lesions characteristic of classic PDD were not observed. To investigate if this ABV2 isolate had reduced virulence, the virus was propagated in duck embryo fibroblasts and inoculated into 2 adult cockatiels by the oral and intramuscular routes. One bird developed clinical signs on day 33 and was euthanatized on day 36. The second challenged bird developed clinical signs on day 41 and was euthanatized on day 45. At necropsy, the proventriculus of both birds was slightly enlarged. Histopathologic examination showed lesions typical of PDD in the brain, spinal cord, heart, adrenal gland, and intestine. A control, uninoculated cockatiel was apparently healthy when euthanatized on day 50. These results show that ABV2 is now the second ABV genotype to be formally shown to cause PDD.

A flock of 14 apparently healthy cockatiels, purchased from a single aviary, was tested for the presence of avian bornavirus (ABV). Twelve birds were found to be intermittently shedding ABV, predominantly genotype 4. Four of the cockatiels known to be shedding ABV4 were subsequently challenged with the tissue culture derived, virulent M24 strain of ABV4. The challenged birds remained in apparent good health until day 92 when one was found dead. The remaining three birds began to exhibit severe neurologic signs, ataxia and convulsions on day 110 and were euthanized. On necropsy, all four birds showed mild proventricular enlargement. In contrast, histopathological examination showed unusually severe and widespread tissue lesions. These included massive lymphocytic infiltration and lymphoid nodule formation within and around the ganglia throughout the gastrointestinal tract. There were similar lesions in the medullary cords of the adrenal gland, heart, spleen, liver, kidney, lungs, pancreas, testes and ovary. Immunohistochemistry demonstrated ABV P antigen not only in the cells of the central and autonomic nervous systems, but also within the mononuclear cells infiltrating the various organs. Two healthy cockatiels, one of which was a known ABV carrier, were inoculated with uninfected tissue culture cells and euthanized on day 150. These birds showed no gross lesions of proventricular dilatation disease but had a mild lymphocytic infiltration in their liver, spleen, and kidneys. Prior infection with ABV did not therefore confer significant immunity on these birds, and may have resulted in increased disease severity following challenge.

Proventricular dilatation disease (PDD) is a common infectious neurologic disease of birds comprising a dilatation of the proventriculus by ingested food as a result of defects in intestinal motility, which affects more than 50 species of psittacines, and is also known as Macaw wasting disease, neuropathic ganglioneuritis, or lymphoplasmacytic ganglioneuritis. Definitive diagnosis of PDD has been problematic due to the inconsistent distribution of lesions. Since its discovery, avian bornavirus (ABV) has been successfully cultured from the brains of psittacines diagnosed with PDD, providing a source of antigen for serologic assays and nucleic acid for molecular assays. This article provides evidence that ABV is the etiologic agent of PDD. Recent findings on the transmission, epidemiology, pathogenesis, diagnosis, and control of ABV infection and PDD are also reviewed.

The fulfillment of Koch’s postulates shows that the virus causes proventricular dilatation disease in parrots., Avian bornavirus (ABV) is a newly discovered member of the family Bornaviridae that has been associated with the development of a lethal neurologic syndrome in birds, termed proventricular dilatation disease (PDD). We successfully isolated and characterized ABV from the brains of 8 birds with confirmed PDD. One isolate was passed 6 times in duck embryo fibroblasts, and the infected cells were then injected intramuscularly into 2 healthy Patagonian conures (Cyanoliseus patagonis). Clinical PDD developed in both birds by 66 days postinfection. PDD was confirmed by necropsy and histopathologic examination. Reverse transcription–PCR showed that the inoculated ABV was in the brains of the 2 infected birds. A control bird that received uninfected tissue culture cells remained healthy until it was euthanized at 77 days. Necropsy and histopathologic examinations showed no abnormalities; PCR did not indicate ABV in its brain tissues.

Avian Borna virus (ABV) has recently been shown to be the causal agent of proventricular dilatation disease (PDD) a lethal neurologic disease of captive psittacines and other birds. An immunoblot assay was used to detect the presence of antibodies against avian Borna virus in the serum of affected birds. A lysate from ABV-infected duck embryo fibroblasts served as a source of antigen. The assay was used to test for the presence of antibodies to ABV in 117 birds. Thirty of these birds had biopsy or necropsy-confirmed proventricular dilatation disease (PDD), while the remaining 87 birds were apparently healthy or were suffering from diseases other than PDD. Sera from 27 of the 30 PDD cases (90%) contained antibodies to ABV. Seventy-three (84%) of the apparently ''healthy'' birds were seronegative. Additionally, sera from seven macaws and one parrot trapped in the Peruvian Amazon were seronegative. Positive sera recognized the bornaviral nucleopro- tein (N-protein). While the presence of antibodies to ABV largely corresponded with the development of clinical PDD, 14 apparently healthy normal birds possessed detectable antibodies to ABV. The existence of a carrier state was confirmed when 13 of 15 apparently healthy cockatiels were shown by PCR to have detectable ABV RNA in their feces. Western blot assays may be of significant assistance in diagnosing proventricular dilatation disease. Many apparently healthy birds may however be seronegative while, at the same time, shedding ABV in their feces.