Cerebellar Hypoplasia in Two Juvenile African Grey Parrots (Psittacus erithacus).

Two sibling 12-week-old DNA-sexed female African grey parrots (Psittacus erithacus) were presented for progressive whole-body tremors, proprioceptive deficits, and an inability to stand unassisted. A third bird in the clutch (DNA-sexed as a male) exhibited no clinical signs. Physical examination of the affected birds revealed ataxia, inability to stand without assistance, and a reliance on their beaks to assist with their mobility. Hematologic and biochemical analyses were normal, as were radiographic images of both birds. Cerebellar disease of unknown origin was diagnosed, and the birds were euthanized. Postmortem examinations of the brains of both parrots revealed marked reduction in cerebellar size and poor folia formation. Microscopic review of the cerebellums demonstrated decreased density of the granular layer and thinning of the molecular layer with poorly organized and differentiated Purkinje fibers, consistent with a diagnosis of cerebellar hypoplasia. There are limited clinical reports and experimental studies examining cerebellar disease in birds. Conditions described have included cerebellar hypoplasia, cerebellar abiotrophy, and cerebellar dysplasia. Although these terms are used interchangeably due to similar clinical signs, histopathology is needed to differentiate between the different disease conditions. This case describes cerebellar hypoplasia that suggested a developmental etiology in 2 African grey parrots.

Polycystic Kidney Disease in 3 Juvenile Rainbow Lorikeets (Trichoglossus moluccanus).

This case series describes polycystic kidney disease in 3 (2 male, 1 female) 2-month-old, juvenile rainbow lorikeets (Trichoglossus moluccanus). The lorikeets diagnosed with polycystic kidney disease were the progeny of full sibling parents that were being intentionally line bred for the purpose of establishing a rainbow lorikeet with the blue color mutation. Clinically the juvenile lorikeets were presented with clinical signs of lethargy, dehydration, regurgitation, anorexia, polyuria, and pelvic limb paresis. Multiple abnormalities were identified on the complete blood count and plasma biochemistry panel, including a normocytic normochromic nonregenerative anemia, hyperuricemia, hyperphosphatemia, hypercalcemia, and azotemia. Severe renal dysfunction was diagnosed in all birds on the basis of clinical presentation, physical examination, and complete blood count and plasma biochemistry results. Radiographically marked renomegaly was noted in one of the cases. Although intensive critical care and supportive therapy was provided, 1 lorikeet died, and the remaining 2 were euthanatized because of client financial constraints and a rapid deterioration of their clinical condition associated with severe renal dysfunction. Postmortem pathology results found that all birds had marked renomegaly, visceral gout, and polycystic kidney disease. Because of the age of the birds and the line breeding within this group of lorikeets, the disease was believed to be inherited. Polycystic kidney disease should be considered as a possible differential diagnosis in juvenile psittacine birds with a history of line breeding when presented with severe renal dysfunction. From the current case series, polycystic kidney disease appears to carry a grave prognosis in juvenile rainbow lorikeets.

Induction of General Anesthesia With Alfaxalone in the Domestic Chicken.

Alfaxalone is a safe and effective anesthetic drug for the induction of general anesthesia in many nonavian companion animal species; however, its efficacy has not been fully evaluated in birds. In premedicated trials, the chickens were sedated with butorphanol 2 mg/kg intramuscularly and midazolam 0.5 mg/kg intramuscularly, 15 minutes before intravenous administration of alfaxalone. The chickens were classified as anesthetized if endotracheal intubation was achieved without eliciting a cough reflex, provoking no patient resistance, and with minimal glottis movement within 15 seconds after the administration of alfaxalone. Qualitative and quantitative data were recorded, including duration of anesthesia, quality of induction, quality of recovery, reflexes, time to sternal recumbency, time to standing, and time to normal behaviors. Survival analysis was used to analyze the association between alfaxalone dosage and premedication with time-related variables. Out of the evaluated doses, the lowest intravenous alfaxalone dose required to achieve anesthetic induction and endotracheal intubation in unpremedicated and premedicated chickens was 7.5 and 4 mg/kg, respectively. The duration of anesthesia for all dose rates within the study ranged from 51 seconds to 4 minutes 45 seconds. Premedication generally improved the quality of induction and recovery, but significantly (P < .001) increased the time required for the chickens to stand after being anesthetized and to return to normal behaviors. Most chickens exhibited varying degrees of hyperactivity on anesthetic induction and recovery. No postinduction apnea or deaths of the subject birds occurred during this investigation.

Transsinus Pinning to Correct Lateral Deviation of the Upper Beak in Juvenile Macaws.

Lateral deviation of the upper beak ("scissor beak" or "wry beak") is a common malocclusion in many species of birds but appears to be a common presentation in macaws (Ara species). This article describes transsinus pinning, a procedure in which a pin is passed through the frontal sinuses, turned parallel to the upper beak, and attached to the tip of the beak with an orthodontic rubber band to provide constant tension on the beak as it grows. The tension of the rubber band is maintained until the beak is considered straight. The results of 16 cases in which this beak-straightening procedure was used are presented. The age of the chicks that had their beaks straightened ranged from 7 to 28 weeks, and they were placed into 2 groups: those younger than 12 weeks (12 chicks; 75%) and those older (4 chicks; 25%). Complete resolution was achieved in 87.5% (14 of 16) of the avian patients that were treated with this procedure. The 2 remaining cases (12.5%) failed to fully respond. The 12 younger birds (75%; age, 7-12 weeks; median, 10 weeks; range, 5 weeks) responded to treatment within 2 weeks (12-85 days; median, 14 days; range, 73 days); the remaining 4 older chicks (25%; age, 14-28 weeks; median, 17.5 weeks; range, 14 weeks) required a longer period (13-90 days; median, 25.5 days; range, 77 days) for the beak to straighten. Transsinus pinning is a simple, effective, and rapid technique for correcting this malocclusion in macaw chicks younger than 16 weeks old. With this approach, in most cases, excellent results can be expected in only 2-4 weeks.

Assessment of avian sperm DNA fragmentation using the sperm chromatin dispersion assay.

Herein we report a simple method for assessing avian sperm DNA fragmentation (SDF) using the sperm chromatin dispersion test (SCDt). The presence of sperm DNA damage was confirmed indirectly by correlating results of the SCDt determined in three bird species with results of a corresponding neutral comet assay (r=0.99; P<0.005). Frozen-thawed spermatozoa of each species were also incubated at 37°C for 5h and the within- and between-species variation of SDF, as an indicator of sperm DNA longevity, examined. The dynamic assessment of SDF using the SCDt revealed species and individual bird (rooster and turkey) differences in sperm DNA longevity.

Adenoviruses in free-ranging Australian bearded dragons (Pogona spp.).

Adenoviruses are a relatively common infection of reptiles globally and are most often reported in captive central bearded dragons (Pogona vitticeps). We report the first evidence of adenoviruses in bearded dragons in their native habitat in Australia. Oral-cloacal swabs and blood samples were collected from 48 free-ranging bearded dragons from four study populations: western bearded dragons (P. minor minor) from Western Australia (n = 4), central bearded dragons (P. vitticeps) from central Australia (n = 2) and western New South Wales (NSW) (n = 29), and coastal bearded dragons (P. barbata) from south-east Queensland (n = 13). Samples were tested for the presence of adenoviruses using a broadly reactive (pan-adenovirus) PCR and a PCR specific for agamid adenovirus-1. Agamid adenovirus-1 was detected in swabs from eight of the dragons from western NSW and one of the coastal bearded dragons. Lizard atadenovirus A was detected in one of the dragons from western NSW. Adenoviruses were not detected in any blood sample. All bearded dragons, except one, were apparently healthy and so finding these adenoviruses in these animals is consistent with bearded dragons being natural hosts for these viruses.

Use of a Vascular Access Port for Antibiotic Administration in the Treatment of Pododermatitis in a Chicken.

Bacterial culture and susceptibility testing results of a wound on the plantar aspect of the foot of a 4-year-old, male chicken with a class IV pododermatitis revealed a multidrug-resistant Escherichia coli bacterium, sensitive to only a few antibiotics including ceftazidime. Concerns over the volume and frequency of antibiotic injections, combined with the likely duration of treatment, led to the use of a vascular access port to facilitate intravenous antimicrobial therapy. The port was placed and maintained for 5 months without complication, and the infection was resolved. This case illustrates the feasibility and application of a vascular port in an avian patient requiring long-term intravenous therapy.

Inhibition of the reproductive system by deslorelin in male and female pigeons (Columba livia).

Veterinary practitioners frequently encounter disorders of the reproductive system in avian patients. Management of these disorders relies on manipulating reproduction by modifying the environment, diet, and social interactions, and by the use of pharmacologic agents and surgery, with varying levels of success and side effects. An alternative is to use the gonadotropin-releasing hormone (GnRH) agonist deslorelin to suppress the pituitary-gonadal axis. To determine the efficacy of deslorelin in domestic pigeons (Columba livia), male (n = 10) and female (n = 10) birds each were implanted intramuscularly with a single long-acting implant containing 4.7 mg deslorelin. Untreated males (n = 11) and females (n = 10) were used as controls. The baseline serum concentration of luteinizing hormone (LH) was assayed at 7, 28, 56, and 84 days after treatment, and egg production was recorded weekly. In females, deslorelin administration significantly reduced serum LH concentrations compared to pretreatment levels at 7, 28, 56, and 84 days (P < .05). In males, deslorelin significantly reduced LH concentrations at 7, 28, and 56 days (P < .05). Female birds treated with deslorelin laid significantly fewer eggs over the course of the study (mean = 1.46, SEM = 0.84) compared with controls (mean = 5.54, SEM = 0.88). Deslorelin treatment had no discernible effect on body weight. Deslorelin is effective for controlling egg laying in female pigeons for at least 49 days, but further research is required to determine the effects on male fertility and the duration of action in both sexes.

Disease screening of three breeding populations of adult exhibition budgerigars (Melopsittacus undulatus) in New Zealand reveals a high prevalence of a novel polyomavirus and avian malaria infection.

Disease surveillance is vital to the management of New Zealand's endemic and threatened avian species. Three infectious agents that are potential threats to New Zealand's endemic birds include avian polyomavirus (APV), beak and feather disease virus (BFDV), and avian malaria. All three agents have been reported in New Zealand; however, possible reservoir populations have not been identified. In this communication, we report the first study of APV, BFDV, and avian malaria in introduced adult exhibition budgerigars (Melopsittacus undulatus) in New Zealand. Blood samples were collected from 90 living adult budgerigars from three breeding locations in the North Island of New Zealand. An overall APV prevalence of 22% was determined using a broad-spectrum nested PCR that amplified the major capsid protein VP1 gene of polyomavirus. Phylogenetic analysis of the VP1 gene revealed a unique isolate of APV, which had a sequence divergence of 32% to previously reported budgerigar fledgling disease strains and 33% to the recently reported New Zealand finch isolate. All of the budgerigars sampled were found to be PCR negative for BFDV, and an overall prevalence of 30% was detected by PCR for avian malaria. Sequencing revealed the presence of ubiquitous malarial strains and also the potentially destructive Plasmodium relictum strain. The results of this study suggest that both APV and avian malaria are present in New Zealand adult budgerigars, and our study highlights the need for further studies to determine whether these pathogens in captive bird populations may be a threat or spill over into New Zealand's endemic and threatened avifauna and whether prevention and control methods need to be implemented.

Sunshine virus in Australian pythons.

Sunshine virus is a recently discovered novel paramyxovirus that is associated with illness in snakes. It does not phylogenetically cluster within either of the two currently accepted paramyxoviral subfamilies. It is therefore only distantly related to the only other known genus of reptilian paramyxoviruses, Ferlavirus, which clusters within the Paramyxovirinae subfamily. Clinical and diagnostic aspects associated with Sunshine virus are as yet undescribed. The objective of this paper was to report the clinical presentation, virus isolation, PCR testing and pathology associated with Sunshine virus infection. Clinical records and samples from naturally occurring cases were obtained from two captive snake collections and the archives of a veterinary diagnostic laboratory. The clinical signs that are associated with Sunshine virus infection are localised to the neurorespiratory systems or are non-specific (e.g. lethargy, inappetence). Out of 15 snakes that were infected with Sunshine virus (detected in any organ by either virus isolation or PCR), the virus was isolated from four out of ten (4/10) sampled brains, 3/10 sampled lungs and 2/7 pooled samples of kidney and liver. In these same 15 snakes, PCR was able to successfully detect Sunshine virus in fresh-frozen brain (11/11), kidney (7/8), lung (8/11) and liver (5/8); and various formalin-fixed paraffin-embedded tissues (7/8). During a natural outbreak of Sunshine virus in a collection of 32 snakes, the virus could be detected in five out of 39 combined oral-cloacal swabs that were collected from 23 of these snakes over a 105 day period. All snakes that were infected with Sunshine virus were negative for reovirus and ferlavirus by PCR. Snakes infected with Sunshine virus reliably exhibited hindbrain white matter spongiosis and gliosis with extension to the surrounding grey matter and neuronal necrosis evident in severe cases. Five out of eight infected snakes also exhibited mild bronchointerstitial pneumonia. Infection with Sunshine virus should be considered by veterinarians investigating disease outbreaks in snakes, particularly those that are associated with neurorespiratory disease.

Avian bornaviruses in psittacine birds from Europe and Australia with proventricular dilatation disease.

To determine whether avian bornaviruses (ABVs) were a factor in proventricular dilatation disease (PDD), we used immunohistochemistry, reverse transcription-PCR, and nucleotide sequence analysis to examine paraffin wax-embedded or frozen tissue samples of 31 psittacine birds with this disease. PDD is a fatal disease of psittacine birds associated with nonsuppurative encephalitis and ganglioneuritis of the upper intestinal tract. Tissue samples had been collected from 1999 through 2008 in Austria, Switzerland, Hungary, and Australia. Immunohistochemical demonstration of viral antigen within the brain and vegetative nerve system of the gastrointestinal tract provides strong evidence for a causative role of ABVs in this condition. Partial sequences of nucleoprotein (p40) and matrix protein (gp18) genes showed that virus in most of our cases belonged to the ABV-2 and ABV-4 groups among the 5 genogroups described so far. Viral sequences of 2 birds did not match any of the described sequences and clustered together in a new branch termed ABV-6.

Bacterial and parasitic diseases of parrots.

As wild-caught birds become increasingly rare in aviculture, there is a corresponding decline in the incidence of bacterial and parasitic problems and an increase in the recognition of the importance of maintaining health through better nutrition and husbandry. Nevertheless, the relatively close confines of captivity mean an increased pathogen load in the environment in which companion and aviary parrots live. This increased pathogen load leads to greater exposure of these birds to bacteria and parasites, and consequently a greater risk of infection and disease. This article discusses bacterial and parasitic infections in companion and aviary parrots. It includes the origins, pathogens, diagnosis, treatment, and some of the associated risk factors.

Ten things I wish I'd learned at university.

To many veterinarians, it may seem that university did not equip or prepare them adequately to deal with exotic animals. In fact, the opposite is true--graduate veterinarians have been trained as problem-solvers and doers. By applying the knowledge and skills learned at University, most veterinarians are more than capable of providing quality medical services to exotic pet owners. Veterinarians wishing to take this further need to accept that they have some learning to do and experience to gain. Those with a true love and affinity for exotic animals will be able to develop their skills and achieve proficiency and competency in one of the most exciting and fast-growing fields of veterinary medicine today.