FATAL GASTRIC DILATATION AND VOLVULUS IN THREE CAPTIVE JUVENILE LINNAEUS'S TWO-TOED SLOTHS (CHOLOEPUS DIDACTYLUS).

Linnaeus's two-toed sloth (Choloepus didactylus) is one of two extant neotropical species of the family Megalonychidae. Despite their being commonly kept under managed care, the digestive physiology of sloths remains poorly understood. Gastrointestinal disease has been reported as a primary or contributing cause of morbidity and mortality in captive two-toed and three-toed (Bradypus spp.) sloths. Gastric dilatation due to gas accumulation ("bloat") has been reported in sloths; however, a literature search failed to yield any published mention of gastric volvulus in any sloth species. Following an inquiry sent to the electronic mailing lists of the American Association of Zoo Veterinarians, the European Association of Zoo and Wildlife Veterinarians, and the LatinVets community, three cases of fatal gastric dilatation and volvulus (GDV) were identified in one male and two female Linnaeus's two-toed sloths from institutions in the United States, Canada, and Germany. All cases occurred in juvenile sloths <1 yr of age. Two animals were primarily hand reared, whereas one was reared primarily by its dam. Two animals were found dead with no overt premonitory signs, whereas one animal died following a 3-wk course of waxing and waning clinical signs consistent with gastric gas accumulation. In all cases, GDV was diagnosed on postmortem examination. Similar to other species, the condition is likely subsequent to a combination of host- and husbandry-related contributing factors. Further research into sloth husbandry is required in order to take an evidence-based approach to their management.

EVALUATION OF PLASMA CARDIAC TROPONIN I IN ASIAN ELEPHANTS (ELEPHAS MAXIMUS) USING TWO CLINICAL ANALYZERS.

Cardiac troponin I (cTnI) is specific to myocardial tissue, highly conserved across taxa, and a reliable indicator of myocardial disease in human and veterinary medicine. Biomarkers, like cTnI, may be useful for cardiac evaluation of elephants because the application of other modalities is complicated by the size of the animal. The goal of this study was to establish observed ranges for plasma cTnI in Asian elephants (Elephas maximus) measured by two point-of-care analyzers. Blood was collected from captive juvenile (≤15 yr; n = 9), adult (16-50 yr; n = 42), and geriatric (>50 yr; n = 16) elephants. Following centrifugation, heparinized plasma was stored at 5°C prior to and in between analyses on iSTAT (Abbott Point of Care Inc, Princeton, NJ 08540, USA) and HUBI-QUANpro (Humiasis Co, Ltd, Anyang-si 14042, South Korea) analyzers. With the exception of two results, plasma concentrations of cTnI were below the limit of quantification (LOQ < 0.05 ng/ml) for the HUBI-QUANpro (n = 64), which prohibited comparison between the two analyzers. Observed ranges were determined for plasma cTnI concentrations reported by the iSTAT for the entire population sampled (n = 58; mean 0.011 ng/ml; SD ± 0.013 ng/ml; range 0.00-0.07 ng/ml; 95% CI 0.008-0.015 ng/ml; median 0.01 ng/ml) and with outliers excluded (n = 50; mean 0.007 ng/ml; SD ± 0.007 ng/ml; range 0.00-0.02 ng/ml; 95% CI 0.005-0.009 ng/ml; median 0.01 ng/ml). No significant differences were observed between age classes (P = 0.70) or sexes (P = 0.34). Higher cTnI concentrations were significantly correlated with increasing age (Pearson's r = 0.426; P = 0.002). Future studies are warranted to investigate the diagnostic potential of plasma cTnI in Asian elephants.

POINT-OF-CARE AND STANDARD LABORATORY REFERENCE INTERVALS FOR COAGULATION VALUES IN ASIAN ELEPHANTS (ELEPHAS MAXIMUS): VARIATION BY AGE CLASS, SEX, AND TIME TO CENTRIFUGATION.

In Asian elephants (Elephas maximus), elephant endotheliotropic herpesvirus causes significant calf mortality. Coagulation testing may aid veterinarians in early identification and management of hemostatic disorders. This study sought to establish reference intervals for select coagulation and platelet values. Blood was collected from clinically healthy Asian elephants (n = 63) in juvenile (≤15 yr old, n = 9), adult (>15 to ≤50 yr old, n = 41), and geriatric (>50 yr old, n = 13) age classes at seven institutions in Kanchanaburi Province, Thailand. Activated clotting time (ACT) was immediately assessed with a handheld analyzer, whereas remaining blood was stored at 5°C in sodium citrate and potassium EDTA collection tubes and transported to a central laboratory. Coagulation values were assessed on an automated blood coagulation analyzer, and platelet values were assessed on a hematology analyzer. Reference intervals were established for ACT, prothrombin time, activated partial thromboplastin time, thrombin time, fibrinogen, platelet count, mean platelet volume, platelet distribution width, and plateletcrit according to the American Society for Veterinary Clinical Pathology guidelines. No significant differences were observed for any value when comparing sex and time to centrifugation. Plasma fibrinogen (P = 0.002) and platelets (P = 0.003) varied significantly by age class, with adults displaying the highest fibrinogen concentrations and geriatric individuals displaying the lowest platelet counts. The ACT kaolin cartridges resulted in high success rates (84.3% feasibility) compared with celite cartridges (4.8% feasibility). Further studies are warranted to stratify reference intervals in accordance with age class trends.

DETECTION OF MYCOPLASMA SP. IN INDOCHINESE BOX TURTLES (CUORA BOURRETI).

Mycoplasma species are important pathogens of captive and free-ranging chelonians. Bourret's box turtle (Cuora bourreti) is a critically endangered species of Indochinese box turtle in the family Geoemydidae. Four privately owned wild-caught Bourret's box turtles were presented for clinical evaluation for anorexia and lethargy following shipment from a reptile wholesaler 3 wk prior. Choanal-cloacal swabs of two of the turtles were positive for Mycoplasma sp. by polymerase chain reaction. Sequencing of the 16S rRNA gene and 16S-23S rRNA intergenic spacer was 99% homologous to an unclassified Mycoplasma sp. previously documented in free-ranging and captive North American species of the family Emydidae. The potential of Mycoplasma sp. to induce disease in Bourret's box turtles is unknown. Global trade in live reptiles is believed to have facilitated this potential expansion of host range.

Pneumonia in a Captive Central Bearded Dragon With Concurrent Detection of Helodermatid Adenovirus 2 and a Novel Mycoplasma Species.

A 4-year-old captive male central bearded dragon ( Pogona vitticeps) was presented for recurrent episodic dyspnea and anorexia with occasional expulsion of oral mucoid discharge. Despite empirical antimicrobial therapy and supportive care, the animal died and was submitted for autopsy. Defining histologic features included heterophilic and lymphocytic interstitial pneumonia, with occasional amphophilic intranuclear inclusions and prominent type II pneumocyte hyperplasia. Transmission electron microscopy revealed intranuclear 80-nm, nonenveloped, hexagonal viral particles within pneumocytes. Helodermatid adenovirus 2 (HeAdV2) was determined as the etiologic agent through pan-adenoviral consensus polymerase (PCR) chain reaction and sequencing. Nucleic acid from a novel Mycoplasma sp. (provisionally called Mycoplasma pogonae) was identified by pan-generic PCR targeting the mycoplasma 16S ribosomal RNA gene with sequencing and phylogenetic analysis. As bacteria morphologically consistent with Mycoplasma sp. were not observed by special stains and transmission electron microscopy, the detection of M. pogonae nucleic acid is of indeterminate significance; however, M. pogonae and HeAdV2 coinfection may have exacerbated disease.

COMPARISON OF ALLIGATOR SNAPPING TURTLE ( MACROCHELYS TEMMINCKII) PLASMA BIOCHEMICAL PROFILES FROM TWO CLINICAL ANALYZERS.

The interpretation of plasma biochemical profiles can be confounded by the methodologies by which samples are analyzed. The goal of this study was to compare agreement between two biochemical analyzers for plasma samples from alligator snapping turtles ( Macrochelys temminckii). Blood was obtained from the dorsal coccygeal vein of captive-reared, juvenile turtles ( n = 34), stored in lithium heparin tubes, and centrifuged to separate plasma from whole blood. Plasma samples were stored at 5°C prior to and in between analyses on VetScan (VetScan2, Abaxis, Union City, CA 94587, USA) and Olympus (Olympus AU640, Beckman Coulter, Brea, CA 92821, USA) analyzers within 2 hr of each other. Agreement between the VetScan and Olympus analyzers was investigated using Passing-Bablok regression analysis for aspartate aminotransferase, creatine kinase, glucose, calcium, phosphorus, total protein, albumin, globulin, potassium, and sodium. Agreement between the two analyzers was outside of acceptance limits and outside of clinical allowable error limits for all analytes as established by the American Society for Veterinary Clinical Pathology. The results of biochemical analyses of alligator snapping turtle plasma cannot be compared between VetScan and Olympus analyzers in a clinical setting. Comparison of biochemical analyses within analyzer units, however, may still be clinically useful. Future studies are warranted to investigate the precision of each analyzer for alligator snapping turtle plasma.

SELECTED OPHTHALMIC PARAMETERS AND POTENTIAL RISK FOR LIGHT-INDUCED CATARACTS IN TWO COLONIES OF CAPTIVE INDIAN FLYING FOXES ( PTEROPUS GIGANTEUS).

Indian flying foxes ( Pteropus giganteus) are adapted to visual foraging in dim light. Nine Indian flying foxes were taken from a captive colony of 25 animals and placed in quarantine, off exhibit, in preparation for shipment to another institution. The exhibit had indirect, natural sunlight and was large enough to allow for flight. The quarantine enclosure was subject to >12 hr/day artificial lighting and did not allow for flight or gliding. Diet was identical between groups. After 13 mo, ophthalmic examination was performed on each animal including evaluation of the anterior chamber, rebound tonometry in upright and hanging positions, measurement of palpebral fissure length, and vertical and horizontal corneal diameters. Bilateral cataracts were observed in 55% (5/9) of the quarantined animals but in none of the animals that remained on exhibit (0/16). Bats housed in the quarantine enclosure had a risk of having cataracts 18 times greater than did bats in the exhibit enclosure (relative risk [RR]: 18.70; 95% confidence interval [CI]: 1.15-303.77). There was no association between cataract presence and age (odds ratio [OR]: 0.99; 95% CI: 0.97-1.02; P = 0.7) or sex (OR: 1.24; 95% CI: 0.17-9.25), but lower body weight was associated with presence of cataracts (OR: 0.98; 95% CI: 0.96-0.99). Other ophthalmic parameters observed were similar to those previously reported for other captive Megachiroptera. This study suggests that chronic exposure to artificial lighting predisposes fruit bats to developing light-induced cataracts.

Diabetes Mellitus With Concurrent Cerebellar Degeneration and Necrosis in a Domestic Goose ( Anser anser domesticus).

A 5-year-old sexually intact male Toulouse goose ( Anser anser domesticus) was presented for ataxia, polyuria, and polydipsia. The goose was cachectic and exhibited head tremors. Results of plasma biochemical analysis and point-of-care glucometry revealed persistent hyperglycemia. Despite supportive care and oral glipizide, the goose died within 48 hours of presentation. Necropsy revealed severe pancreatic atrophy and fibrosis with regionally extensive cerebellar encephalomalacia and generalized Purkinje cell degeneration and necrosis. On a wet basis, hepatic zinc concentration was determined to be twice the reference interval by atomic absorption spectroscopy. Based on these findings, the pancreatic insufficiency with secondary diabetes mellitus was attributed to chronic zinc toxicosis. Despite birds' relative resistance to high blood glucose concentrations, prolonged hyperglycemia is suspected to have caused selective Purkinje cell degeneration and necrosis by glial activation, mitochondrial dysfunction, and glutamate toxicity, which resulted in the clinically observed motor deficits. This is consistent with experimental diabetic rat models. This case highlights the need for further investigation of the complex pathophysiology of diabetes mellitus in birds.

Cardiovascular tolerance of intravenous bupivacaine in broiler chickens (Gallus gallus domesticus) anesthetized with isoflurane.

OBJECTIVE: To determine the median effective dose (ED50) of intravenous (IV) bupivacaine associated with a 50% probability of causing clinically relevant cardiovascular effects [defined as 30% change in heart rate (HR) or mean arterial pressure (MAP)] in chickens anesthetized with isoflurane. STUDY DESIGN: Randomized up-and-down study. ANIMALS: A total of 14 Ross-708 broiler chickens (Gallus gallus domesticus) weighing 1.70-2.75 kg. METHODS: Anesthesia was induced and maintained with isoflurane. Monitoring included the electrocardiogram and invasive arterial pressures. Chickens were administered bupivacaine IV over 2 minutes using a dose based on the response of the previous animal. Dose was decreased when HR and/or MAP in the previous animal increased or decreased ≥30% after bupivacaine administration, or increased when HR or MAP changed <30%. The ED50 was defined as the dose resulting in ≥30% variation in HR or MAP in 50% of the population studied. RESULTS: The IV ED50 of bupivacaine was 1.94 mg kg-1 using Dixon's up-and-down method and 1.96 mg kg-1 by logistic regression. CONCLUSIONS AND CLINICAL RELEVANCE: These results suggest that 1.33 and 1.96 mg kg-1 of IV bupivacaine are associated with a respective 1 or 50% probability of a clinically significant change in MAP in isoflurane-anesthetized chickens. Identification of the cardiovascular changes associated with different doses of bupivacaine can be used as the basis for studies of therapeutic applications in the domestic chicken. Further studies are required to determine interspecies variation.

EFFECTS OF PLANT PROTEIN DIETS ON THE HEALTH OF FARMED AMERICAN ALLIGATORS (ALLIGATOR MISSISSIPPIENSIS).

The objective of this prospective, blinded study was to compare plasma biochemical values and gross and histologic evaluation of kidney and liver from American alligators ( Alligator mississippiensis ) fed extruded diets with protein derived from animal or plant sources. Alligators in two treatment groups were fed an extruded diet with protein derived primarily from plant products for 7 (n = 20) or 10 (n = 20) mo prior to harvest. A control group (n = 20) was fed a commercial diet with protein derived from animal products for the duration of the study. Plasma biochemistry panels were obtained and gross and histologic examination of kidney and liver tissues was conducted for each animal. No differences were found between alligators fed diets with animal or plant protein in terms of either biochemistry profiles or gross or histologic examination of kidney and liver. Plant-based diets, fed for up to 10 mo, do not appear to have any ill effects on the kidney or liver of American alligators.

Into the large ears: otitis externa associated with nematodes, mites, and bacteria in Asian elephants (Elephas maximus).

BACKGROUND: The Asian elephant (Elephas maximus), which is an endangered species, harbors several parasites. Among the ectoparasites that it harbors, ear mites of the genus Loxanoetus have the potential to cause external otitis, an inflammation that may also be associated with the presence of other microorganisms. We assessed the relationships between ear mites, nematodes, yeast, bacterial rods, and cocci sampled from the ears of captive Asian elephants in Thailand. In addition, we discuss the possibility that dust-bathing behavior may be triggered by ear mite infestation, and that this in turn may lead to contamination of the ears with soil microorganisms. METHODS: Legally owned captive Asian elephants (n = 64) were sampled. Ear swabs were individually collected from both ears and microscopically examined for the presence of mites, nematodes, yeast, bacterial rods, cocci, and host cells. Mites and nematodes were identified to species level using morphological and molecular methods. RESULTS: Loxanoetus lenae mites were present in 43.8% (n = 28/64) of the animals (19 animals with mites in one ear and nine animals with mites in both ears). Nematodes of the genus Panagrolaimus were detected in 23.4% (n = 15/64) of the animals (10 with nematodes in one ear and five with nematodes in both ears). In adult elephants (Fisher's exact test, P = 0.0278) and female elephants (Fisher's exact test, P = 0.0107), the presence of nematodes in both ears was significantly associated with the presence of mites. In addition, higher categorical burdens of nematodes were also significantly associated with the presence of mites (Fisher's exact test, P = 0.0234) and epithelial cells (Fisher's exact test, P = 0.0108), and marginally significantly associated with bacterial cocci (Fisher's exact test, P = 0.0499). CONCLUSIONS: The presence of L. lenae mites in the ear canals of the Asian elephants was significantly associated with the occurrence of other microorganisms, such as soil nematodes, bacteria and yeasts. The presence of mites in their ears may increase the dust-bathing behavior of elephants which, if confirmed, represents a further paradigmatic example of a parasitic infestation affecting animal behavior.

Sedation and Anesthesia of Amphibians.

Amphibians commonly are managed under human care for research, education, conservation, and companionship and frequently are in need of sedation, anesthesia, or end-of-life care involving euthanasia. Objective investigation of sedative and anesthetic protocols in these taxa still is in its infancy, but knowledge of current best practices is paramount to appropriate care. Tricaine methanesulfonate delivered via immersion (bath) is the most common anesthetic agent in amphibians, but several other effective techniques have been identified. This summary provides a comprehensive review of the current evidence-based literature regarding amphibian sedative, anesthetic, and euthanasia techniques.

Local and Regional Anesthesia in Zoological Companion Animal Practice.

Local anesthetics provide analgesia and can be incorporated into multimodal anesthetic protocols. They work by blocking the voltage-dependent sodium ion channels along neurons that mediate nociception. Systemically, these drugs can be cardiotoxic in a dose-dependent manner. Lidocaine and bupivacaine are the most commonly used local anesthetics and their use has been reported in all classes of vertebrates. Despite anecdotal reports to the contrary, zoologic companion animals are unlikely to be more susceptible to the cardiotoxic effects of local anesthetics than domestic small animals. Local anesthetics can be clinically useful for analgesia and anesthesia in zoologic companion animal practice.

Point-of-care ketone meters may be used to estimate serum ß-hydroxybutyrate concentrations in healthy African penguins (Spheniscus demersus).

OBJECTIVE: To evaluate the agreement between 3 point-of-care (POC) devices and a reference laboratory for measuring ß-hydroxybutyrate (ß-HB) concentration in African penguin (Spheniscus demersus) whole blood (WB) and plasma samples and the precision of each POC device for measuring ß-HB concentration in plasma samples. ANIMALS: 48 healthy African penguins. PROCEDURES: Blood was obtained from the right jugular vein of each penguin, and ß-HB concentration was measured on each POC device using fresh WB and heparinized plasma and at the reference laboratory using plasma. ß-HB concentration was measured in plasma on each POC device. RESULTS: All devices overestimated serum ß-HB concentrations on average by 0.46 mM relative to the reference laboratory. WB samples had less error than plasma for meters A and C. Meter A had the lowest total error observed (26.4%) and the lowest mean difference (0.19 mmol/L) relative to the reference laboratory. Controlling for other factors, the magnitude of disagreement was not affected by sex, age, packed cell volume, or serum total solids concentration. CLINICAL RELEVANCE: WB, not plasma, should be used for measurement of ß-HB concentration on the POC meters tested. Meter A showed good correlation with the reference laboratory for WB. The use of POC devices for the measurement of ß-HB concentration may be acceptable when laboratory analyzers are not available. Further research is needed for clinical application and the diagnostic value of POC meters compared with reference laboratories.

Hematologic and plasma biochemical prognostic indicators for stranded free-ranging phocids presented for rehabilitation.

This retrospective study used data obtained from medical records of 530 stranded free-ranging harbor (Phoca vitulina), grey (Halichoerus grypus), harp (Pagophilus groenlandicus), and hooded seals (Cystophora cristata) presented to the Marine Mammal Stranding Center in Brigantine, New Jersey from January 1998 through December 2016. The objective was to identify hematological and plasma biochemical parameters of seals at time of presentation that were associated with successful rehabilitation and with duration of hospitalization using univariate and multivariate logistic regressions. At presentation, animals that subsequently survived rehabilitation had greater alkaline phosphatase activity and absolute lymphocyte and total calcium concentrations and lower blood urea nitrogen, sodium, chloride, phosphorus, and total bilirubin concentrations and lower aspartate aminotransferase and alanine aminotransferase activities than animals that eventually died or were euthanized while under care. Results suggest that young, actively growing animals are more likely to survive rehabilitation and that bloodwork consistent with dehydration, systemic disease, and exhaustion are negative prognostic indicators. These results provide prognostic indicators that may aid clinical decision-making for seals presented for rehabilitation.

Pathology in Practice.

In collaboration with the American College of Veterinary Pathologists.

Verminous meningoencephalomyelitis in a red kangaroo associated with Angiostrongylus cantonensis infection.

Angiostrongylus cantonensis is a zoonotic parasitic helminth that normally resides in the pulmonary arteries and the right ventricle of rats (Rattus sp.), the definitive host, where it causes little disease. Humans, dogs, opossums, and various zoo animals are "accidental" hosts. Here we report verminous meningoencephalomyelitis caused by A. cantonensis in a 9-mo-old male red kangaroo (Macropus rufus). The kangaroo was first presented lethargic, recumbent, and hypothermic, with severe muscle wasting. Within 3 wk, he progressed to non-ambulatory paraparesis and died. Gross examination revealed multifocal areas of dark-brown discoloration, malacia, and cavitation in the brain and the spinal cord. Histologically, there were several sections of nematodes surrounded by extensive areas of rarefaction, hemorrhage, spongiosis, neuronal necrosis, and gliosis. Based on size, morphology, and organ location, the nematodes were identified as subadult males and females. Interestingly, an eosinophilic response was largely absent, and the inflammatory response was minimal. A. cantonensis infection had not been reported previously in a red kangaroo in Louisiana or Mississippi, to our knowledge. Our case reaffirms the widespread presence of the helminth in the southeastern United States and indicates that A. cantonensis should be considered as a differential in macropods with neurologic clinical signs in regions where A. cantonensis is now endemic.

Ticks infesting the endangered Italian hare (Lepus corsicanus) and their habitat in an ecological park in southern Italy.

The Italian hare (Lepus corsicanus) is an endangered species whose natural populations have decreased in recent years. This study's objective was to identify ticks infesting hares and their habitats in a wildlife reserve in southern Italy. In June 2009, ticks were collected by dragging in three transects set in a meadow habitat within an enclosure inhabited by hares and in three similar transects outside this enclosure. Fifty-five ticks were collected by dragging, being 54 inside and 1 outside the enclosure. Ticks were identified as Hyalomma marginatum (34 males, 17 females), Dermacentor marginatus (2 males, 1 female), and Rhipicephalus bursa (1 female). In September 2009, ticks were collected from 17 Italian hares and identified as Ixodes ricinus (2 larvae, 45 nymphs, 35 males, 37 females), Rhipicephalus turanicus (2 males, 1 nymph), and Hyalomma sp. (165 nymphs). PCR amplification and sequencing of a partial region of the 12S rDNA gene of Hyalomma nymphs allowed their identification as H. marginatum. This study suggests that host presence is a factor determining the level of environmental tick infestation as well as the free-living tick species in the study area and that Italian hares are hosts for I. ricinus and H. marginatum. Studies to assess whether these ticks could limit the survival and fitness of Italian hares and affect their conservation status are needed. Moreover, it is necessary to investigate whether these ticks are infected with pathogens of medical and veterinary concern.

Outcomes of 4819 cases of marine animals presented to a wildlife rehabilitation center in New Jersey, USA (1976-2016).

Understanding marine animal stranding patterns can aid rehabilitation efforts and evaluations of ecosystem health. The goal of this retrospective study was to identify factors associated with outcome of marine animals presented to a rehabilitation facility in Brigantine, New Jersey, USA. Records of 4819 phocids, cetaceans, and sea turtles were reviewed. Taxa, age, sex, season, and outcome (natural death, euthanasia, transfer to another facility, and successful release) were recorded for each case. Binary logistic regression was employed to identify predictors associated with release, and a multivariate logistic regression model was developed to evaluate whether the association between taxa and chance of release persisted after adjustment for the other variables. Phocids were most likely to strand during winter. Phocids and sea turtles that stranded alive were more likely to be released than to die under care or be euthanized. Taxa, age, and season were all significantly associated with the probability of release. These results provide a reference for phocid, cetacean, and sea turtle stranding and rehabilitation in part of the mid-Atlantic region. Critical evaluation of wildlife rehabilitation is indicated to audit the success of efforts and to assess threats to free-ranging populations.