Dungeons and Dragons: Culture Differences in Attitudes Toward Exotic Animals.

The way exotic animals are viewed around the world differ. These views and attitudes are constantly evolving and may eventually converge in the way that cats and dogs are now widely accepted as part of most societies around the world. The choice and popularity of exotic animal species as pets is a complex interaction of many different factors, including legislation and availability. Media representation may be a factor too, but there has been very little evidence to demonstrate this. Regardless of the region, exotic animal practice appears to be an area of veterinary practice that is on the rise.

A Critical Review on the Dosing and Safety of Antifungals Used in Exotic Avian and Reptile Species.

Antifungals are used in exotic avian and reptile species for the treatment of fungal diseases. Dose extrapolations across species are common due to lack of species-specific pharmacological data. This may not be ideal because interspecies physiological differences may result in subtherapeutic dosing or toxicity. This critical review aims to collate existing pharmacological data to identify antifungals with the most evidence to support their safe and effective use. In the process, significant trends and gaps are also identified and discussed. An extensive search was conducted on PubMed and JSTOR, and relevant data were critically appraised. Itraconazole or voriconazole showed promising results in Japanese quails, racing pigeons and inland bearded dragons for the treatment of aspergillosis and CANV-related infections. Voriconazole neurotoxicity manifested as seizures in multiple penguins, but as lethargy or torticollis in cottonmouths. Itraconazole toxicity was predominantly hepatotoxicity, observed as liver abnormalities in inland bearded dragons and a Parson's chameleon. Differences in formulations of itraconazole affected various absorption parameters. Non-linearities in voriconazole due to saturable metabolism and autoinduction showed opposing effects on clearance, especially in multiple-dosing regimens. These differences in pharmacokinetic parameters across species resulted in varying elimination half-lives. Terbinafine has been used in dermatomycoses, especially in reptiles, due to its keratinophilic nature, and no significant adverse events were observed. The use of fluconazole has declined due to resistance or its narrow spectrum of activity.

MANAGEMENT OF ENTAMOEBA INVADENS IN THE HERPETOLOGICAL COLLECTION AT THE SINGAPORE ZOO.

Amebiasis caused by Entamoeba invadens is an important disease in reptile collections, causing severe morbidity and mortality. Surveillance of the parasite at the Singapore Zoo was carried out over a 4-yr period by PCR testing on reptiles that presented with lethargy and enteritis for disease investigation. Asymptomatic reptiles sharing the same enclosures as positive individuals were also tested as part of outbreak investigation. Animals in the collection that tested positive for the parasite were treated with metronidazole at various doses, with the addition of paromomycin for two cases, until a negative PCR test result was obtained at the end of the treatment course. A total of 97 samples from 49 individuals across 19 species of reptiles were obtained, of which 24 samples (24.7%) from 19 animals were positive for E. invadens. Of these positive samples, 11 samples were for disease investigation, eight samples for outbreak surveillance, and five samples for treatment monitoring. Treatment was initiated for 10 animals, four of which were showing clinical signs of disease. The parasite was cleared in nine of these 10 animals (90%), with eight animals receiving metronidazole as a sole therapeutic agent. A total of nine animals died of the disease, four of which (44.4%) presented dead or died within 24 h of presentation. Necrotizing enteritis was a consistent postmortem finding resulting in gastrointestinal perforation in two cases, and coelomic adhesions and hepatic trophozoites were each seen in five animals. The results suggest that the management of Entamoeba epizootics in the collection requires prompt outbreak investigation. Diagnosis of the disease with advanced diagnostic tools like PCR, endoscopy, and ultrasonography and treatment with metronidazole in both symptomatic and asymptomatic animals may reduce mortalities during an outbreak.

MANAGEMENT OF A FATAL OUTBREAK OF STRONGYLOIDIASIS IN A CAPTIVE POPULATION OF PANTHER CHAMELEONS (FURCIFER PARDALIS) WITH IVERMECTIN.

An outbreak of the nematode Strongyloides sp. occurred in a population of 18 male and 29 female panther chameleons (Furcifer pardalis) at the Singapore Zoo. The parasite was first detected in one individual during routine microscopic examination of feces using the direct examination and magnesium sulfate flotation methods. The parasite was later found to have a closest match (98.96%) with Strongyloides sp. Okayama by DNA sequencing. Over a period of 6 mon, 97.9% (46/47) of the panther chameleons tested positive for the parasite, and 25.5% (12/47) of the animals died due to the disease. All the animals that died were female. Of the positive tests, magnesium sulfate flotation identified the parasite 98.1% (105/107) of the time, compared to direct fecal microscopy, which identified the parasite only 43.9% (47/107) of the time. Parasite eggs were detected in 100% (105/105) of the positive magnesium sulfate flotation tests but only 66.0% (31/47) of the positive direct fecal microscopy tests. Parasite larvae were detected in 61.7% (29/47) of the positive direct fecal microscopy tests but only 9.5% (10/105) of the magnesium sulfate flotation tests. Treatments with fenbendazole and pyrantel pamoate at published doses were ineffective at eliminating the parasite. Ivermectin (0.2 mg/kg PO q2wk for two doses) was successful at treating the parasite, with all animals testing negative for the parasite at the end of the treatment course without any observed adverse reactions. However, complete eradication of the parasite could not be achieved, as Strongyloides sp. could still be detected in the population on routine coproscopy intermittently over 3 yr. There were no further mortalities due to the disease with prompt treatment with ivermectin. Strongyloidiasis may cause high morbidity in panther chameleons, but severe disease leading to mortality can be prevented with the use of ivermectin.

Enterococcus casseliflavus infection in a captive Southern Cassowary (Casuarius casuarius): clinical and post-mortem findings.

An adult 22-year-old, male southern cassowary (Casuarius casuarius) presented for lethargy, dysorexia and soft feces. Clinical findings under chemical immobilization were unremarkable except for heterophilic toxic changes on blood smear, reduced albumin/globulin ratio and potentially elevated liver parameters. The animal was treated for suspected hepatobiliary insufficiency and received supportive treatment with daily subcutaneous fluids and medication and was monitored with a quality-of-life assessment. It was eventually euthanized after further deterioration. Post-mortem examination revealed vegetative valvular endocarditis, bile duct obstruction, cholangiohepatitis and splenitis with intralesional Enterococcus casseliflavus isolated. This is a first documented case of E. casseliflavus infection in a bird with multiorgan involvement.

A comparison of staff presence and signage on zoo visitor behavior.

Many zoos favor the use of signage to encourage learning and positive visitor experiences as well as discourage negative behaviors by visitors because of its simplicity, relatively low maintenance needed, and low cost. However, current literature suggests that conventional signage has limited impact on visitors in zoos. This study hypothesized that visitors would be less likely to exhibit negative behaviors (e.g., feeding and touching) in the presence of uniformed staff compared to signage. The study was conducted twice a day over 4 weeks with one condition per week (Baseline, Signage, Staff, and Signage + Staff). The total number of visitors and the frequency of negative visitor behaviors were observed. These behaviors reduced from 14.0% (Baseline; no signage and no staff) and 13.1% (Signage), to 4.8% (Staff) and 6.1% (Signage + Staff). Both the Staff and Signage + Staff conditions were significantly lower than the Baseline and Signage conditions. However, signage alone did not significantly differ from the baseline condition, when no intervention was implemented, and staff and signage together did not significantly differ from staff alone. This was also observed in both negative visual behaviors and negative tactile behaviors from visitors. The results suggest that methods other than signage may be more effective at reducing undesired visitor behaviors. This study could guide the design of future signage or even potentially encourage zoos to reduce reliance on signs and employ other strategies.

EVALUATION OF SYMMETRIC DIMETHYLARGININE AS AN ENDOGENOUS MARKER OF RENAL DISEASE IN GREATER FLAMINGOS (PHOENICOPTERUS ROSEUS).

Detection of renal disease in birds is currently reliant on biochemical measures such as uric acid, which is only elevated after significant renal compromise has occurred. Symmetric dimethylarginine (SDMA) production has not been previously evaluated in birds and no reference intervals (RI) for measurement exist in avian species. This study aimed to develop an RI for SDMA in greater flamingos (Phoenicopterus roseus) and evaluate the association between SDMA levels and renal disease. Blood from 60 flamingos was collected for RI development and the RI of SDMA was found to be 11.8-34.2 µg/dl. Symmetric dimethylarginine showed a strong positive correlation with uric acid, a moderate positive correlation with creatine kinase, and moderate negative correlations with total protein, albumin, and glucose. No correlation was found with pododermatitis score or body condition. Using the SDMA RI, six clinical cases were included for assessment of the clinical relevance of SDMA in renally compromised patients. All birds that were euthanized had elevated SDMA levels and severe renal or systemic pathology on necropsy.

A Critical Review on the Pharmacodynamics and Pharmacokinetics of Non-steroidal Anti-inflammatory Drugs and Opioid Drugs Used in Reptiles.

Non-steroidal anti-inflammatory drugs (NSAIDs) and opioids are analgesics used for moderate to severe pain in many animals, including reptiles. However, reptilian dosing regimens are often extrapolated from other animal species. This is not ideal as inter- and intra-species variability in physiology may result in varied drug disposition. Therefore, this critical review aims to collate data from pharmacological studies of selected NSAIDs and opioids performed in reptile and provide an analysis and discussion on the existing pharmacodynamic knowledge and pharmacokinetic data of NSAIDs and opioids use in reptiles. Additionally, key pharmacokinetic trends that may aid dosing of NSAIDs and opioids in reptiles will also be highlighted. Most of the existing reports of NSAID used in reptiles did not observe any adverse effects directly associated to the respective NSAID used, with meloxicam being the most well-studied. Despite the current absence of analgesic efficacy studies for NSAIDs in reptiles, most reports observed behavioural improvements in reptiles after NSAID treatment. Fentanyl and morphine were studied in the greatest number of reptile species with analgesic effects observed with the doses used, while adverse effects such as sedation were observed most with butorphanol use. While pharmacokinetic trends were drug- and species-specific, it was observed that clearance (CL) of drugs tended to be higher in squamates compared to chelonians. The half-life (t1/2) of meloxicam also appeared to be longer when dosed orally compared to other routes of drug administration. This could have been due to absorption-rate limited disposition. Although current data provided beneficial information, there is an urgent need for future research on NSAID and opioid pharmacology to ensure the safe and effective use of opioids in reptiles.

A Critical Review of the Pharmacokinetics, Pharmacodynamics, and Safety Data of Antibiotics in Avian Species.

In avian medicine, the use of antibiotic dosing regimens based on species-specific pharmacological studies is ideal. However, due to a lack of such studies, dose extrapolation, which may cause inefficacy and toxicity, is common practice. Multiple searches were performed using the PubMed and Web of Science databases to extract relevant pharmacological studies performed in exotic avian species. The pharmacokinetics (PK), pharmacodynamics (PD), and safety data of the selected antibiotics (enrofloxacin, marbofloxacin, gentamicin, amikacin, ceftiofur, doxycycline, and amoxicillin/clavulanate) from these studies were reviewed. This review aimed to identify trends amenable for safe inter-species dose extrapolation and provide updated findings on dosing regimens that are safe and efficacious for various exotic avian species. We observed that the half-life of antibiotics appears to be shorter in the common ostrich and that amikacin may be amenable to inter-species dose extrapolation as it is safe and shows little inter-species PK and PD variation. Species-specific enrofloxacin dosing regimens that were not listed in the Exotic Animal Formulary (5th ed.) were found for Caribbean flamingos, African penguins, southern crested caracaras, common ostriches, and greater rheas. Specific dosing regimens recommended for psittacine birds (doxycycline 130 mg/kg medicated water) and ratites (PO doxycycline 2-3.5 mg/kg q12 h, PO enrofloxacin 1.5-2.5 mg/kg q12 h and IM enrofloxacin 5 mg/kg q12 h) in the formulary may not be effective in budgerigars and common ostriches, respectively. Apart from the lack of species-specific pharmacological studies, a lack of multiple dose studies was also noted.

Pharmacokinetic profile and effect on the faecal microbiome of a single dose of pradofloxacin oral suspension in the rabbit (Oryctolagus cuniculus).

Fluoroquinolones are often administered to pet rabbits given their perceived safety and limited effects on anaerobic gut microbiota. However, the pharmacokinetics and relative safety of pradofloxacin, a third-generation veterinary fluoroquinolone with a much broader spectrum of activity, have not been reported in this species. Here, we determined the pharmacokinetic profile of a single dose of oral pradofloxacin in rabbits and evaluated effects on the faecal microbiome. Four mature female rabbits were administered pradofloxacin (25 mg/ml oral suspension), at a dose of 7.5 mg/kg. The pradofloxacin median (range) Tmax was 4.50 (2.00-5.00) h, Cmax 600.66 (395.85-886.72) ng/ml and t½ was 1.27 (0.12-1.39) h. These results indicated that oral absorption of pradofloxacin was slower, and elimination faster compared with other fluoroquinolones in healthy rabbits, as well as relative to cats and dogs. Following treatment with pradofloxacin, faecal microbiota profiling showed some compositional differences between treated and control animals. This was the result of a significant decrease in the abundance of Proteobacteria, in particular bacteria belonging to the Pseudomonas, Atopostipes and Parabacteroides genera. The pharmacokinetic profile of pradofloxacin in rabbits should be further studied by increasing the sample size and using multiple-dose protocols (i.e. 7 days) to confirm safety. Further information on the effects of protein binding, higher dosages and disease on pradofloxacin pharmacokinetics in rabbits are needed before an accurate dosing regimen can be recommended.

Application of Epidemiology and Principles of Herd/Flock Health for the Exotic Animal Veterinarian.

Against a backdrop of climate change and epidemics, the exotic animal veterinarian is well positioned to detect emerging and exotic disease threats, prevent and control zoonotic diseases, and identify antimicrobial resistance. Within the traditional context of animal and public health, epidemiology has had a focus on veterinary preventive health and in disease investigation and control particularly in food animal and safety application. The understanding of preventive health management and veterinary epidemiology expands the repertoire of the clinical veterinarian to advise and implement and evaluate group animal health programs and biosecurity measures as well as conduct disease investigations.

Managing Disease Outbreaks in Captive Flocks of Birds.

The modern avian practitioner may be called upon to manage disease outbreak in aviary or zoologic bird flocks. Traditionally, managing these types of disease events has been based on avicultural production principles, which may require modification to adapt to the modern leisure, educational, or exhibition aviary. We discuss how principles of avicultural medicine and disease investigation may be adapted to the aviary flock and illustrate these modified principles with real-world examples.

Pharmacokinetic profile of a single dose of an oral pradofloxacin suspension administered to eastern long-necked turtles (Chelodina longicollis).

The pharmacokinetics of fluoroquinolones in chelonians are well described but this does not extend to pradofloxacin, a broad-spectrum veterinary fluoroquinolone available as an oral suspension for cats and dogs. The aim of this study was to investigate the single-dose pharmacokinetic profile of pradofloxacin oral suspension at 7.5 mg/kg in eastern long-necked turtles (Chelodina longicollis). Eight treated turtles were sampled at multiple time points up to 168 hr. Plasma concentrations were measured using high-performance liquid chromatography. Pradofloxacin was quantifiable for up to 48 hr after drug administration. The Tmax (9.0 hr) and T½ to 48 hr (13.16 hr) were longer, and the Cmax (0.2 µg/ml) and AUC0-24 (2.2 hr*µg/ml) lower, than previously reported in cats and dogs. Pradofloxacin was measurable in tank water samples for up to 48 hr. No adverse effects were observed in six turtles administered 7.5 mg/kg sid for 7 days. Using mammalian MIC data, the AUC0-24 /MIC ratios for a range of bacterial isolates suggest that this dose of pradofloxacin in turtles is unlikely to be effective against many bacterial pathogens.

Organ Histopathology and Hematological Changes Associated With Heat Exposure in Australian Desert Birds.

An inability of the body to appropriately respond to extreme temperatures will result in pathological changes to vital organs and adverse hematological changes. Mild heat exposure of a bird to a temperature above the zone of thermoneutrality can induce subclinical heat stress, which may be a precursor to illness. The ability to identify subtle changes that may be associated with subclinical heat stress can be important in early diagnosis and treatment of heat stress in birds. Pathological changes to internal body organs, post-heat exposure, were microscopically examined in 13 budgerigars (Melopsittacus undulatus), 15 zebra finches (Taeniopygia guttata), and 8 diamond doves (Geopelia cuneata) as model species for the bird orders Psittaciformes, Passeriformes, and Columbiformes, respectively. There was mild to moderate congestion of the lungs of 28/36 birds examined, including all of the budgerigars and diamond doves. In 8/15 zebra finches no significant lung congestion was noted. Interstitial and pulmonary hemorrhage was in observed in one diamond dove. The most common hepatic pathologic change identified was micro- and macro-vesicular hepatocellular vacuolation (4/15 zebra finches, 5/13 budgerigars, and 8/8 diamond doves). There was mild to moderate congestion in the kidneys of 1/15 zebra finch, 2/ 13 budgerigars, and 4/8 diamond doves, as well as in the gastrointestinal tract of 1/15 zebra finch and 7/8 budgerigars. Budgerigars showed a decrease in hematocrit and a significant change in the numbers of heterophils and lymphocytes following heat exposure. The basophil population of cells remained relatively stable in both budgerigars and diamond doves. These findings indicate avian species differences in body organ and hematological changes following exposure to similar elevations in environmental temperatures.

Intralesional methylprednisolone injection as an adjunct treatment for peri-cloacal pyogranuloma in an African penguin (Spheniscus demersus).

An African penguin (Spheniscus demersus) presented with a large peri-cloacal mass. The mass was diagnosed as a pyogranuloma histologically, with multifocal to coalescing inflammatory responses in the subcutis and keratinized simple stratified squamous epithelium overlying the surface. The patient was prescribed 125 mg/kg oral clavulanic acid/amoxycillin twice a day and 20 mg/kg oral terbinafine once a day for 14 days, but there was no change in the size of the mass 4 days after therapy, so a decision was made to administer 1 mg/kg of intralesional methylprednisolone. Fourteen days later, the mass resolved with no further recurrence. This case demonstrated that intralesional methylprednisolone used with antibiotic and antifungals was effective in resolving a peri-cloacal pyogranuloma and without any side effects.

The use of a 3D-printed prosthesis in a Great Hornbill (Buceros bicornis) with squamous cell carcinoma of the casque.

The advent of new technologies in medical imaging and 3D printing in recent years has made customization of surgical tools and implants more accessible, revolutionizing many surgical fields. In many human diseases, these implants have led to superior surgical outcomes and greatly improved patients' quality of life. Thus, it is of great interest to apply these technologies to the treatment of animal diseases. In this study, we report the use of computed tomography (CT) and 3D printing for the treatment of a Great Hornbill at Jurong Bird Park that was diagnosed with squamous cell carcinoma of the casque. A 3D printed prosthesis that perfectly fitted the subject was implanted to replace its resected casque. The subject exhibited natural eating behaviour with no post-operative complications. Using this case as an example, the positive outcomes suggest a great potential in applying these technologies to the treatment of other wildlife diseases.

Physiological, biochemical and histopathological changes associated with heatstroke in the galah (Eolophus roseicapilla) and rock dove (Columba livia).

The pathophysiology of heat illnesses in birds has not been well characterized. In this study, we describe the changes in heart rate, respiratory rate, blood biochemistry and histopathological findings in galahs and rock doves after heat exposure under standardized conditions designed to induce heatstroke. Birds in the heat-exposed group were exposed to environmental heat stress and compared to control birds. Both groups of birds were under general anaesthesia throughout the experiment and serial blood collections were performed for biochemical analyses, while organs were collected at the end of the experiment for histopathology. No electromyography traces consistent with the onset of heat cramps were observed in any of the birds. Biochemical changes suggestive of skeletal muscle and hepatocellular injury, including hyperkalaemia and increased serum muscle and hepatic enzyme activities, were often observed in heat-exposed galahs and rock doves at the onset of heatstroke. Microscopic analyses did not reveal any significant cardiac changes, although some lungs had signs of acute congestion. Some heat-exposed rock doves had microscopic changes indicative of necrosis in the pectoral muscle. There were significant hepatic changes in some heat-exposed galahs, but not in rock doves. This suggests that there may be species differences amongst birds in the organs most affected by heatstroke. The observed species differences in the physiological, biochemical and histopathological changes indicate that bird species should be studied separately for clinical syndromes such as heatstroke. RESEARCH HIGHLIGHTS Biochemical changes suggestive of skeletal muscle and hepatocellular injury in heat-exposed galahs and rock doves at the onset of heatstroke No electromyography traces consistent with the onset of heat cramps were observed Some heat-exposed rock doves had indications of necrosis in the pectoral muscle There were significant hepatic changes in some heat-exposed galahs.