Maxillary Ameloblastoma in an Asiatic Black Bear (Ursus thibetanus).

An approximately 30-year-old intact female Asiatic black bear (Ursus thibetanus) was presented for annual examination and a history of ptyalism. A large 9.5 cm × 5 cm × 5 cm, firm, round mass was identified attached to the hard palate on physical examination. A computed tomography scan was performed, and the heterogeneous, mineral-attenuating mass was seen arising from the right aspect of the palatine bone and extending rostrally to the level of the last maxillary molars, caudally into the oropharynx, and dorsally into the nasal choana. Surgical debulking was performed to remove the portion of the mass within the oral cavity. Histopathologic analysis was consistent with a keratinizing ameloblastoma. Nine months postoperatively, the patient was asymptomatic for the tumor. The patient was euthanized 23-months postoperatively, and severe diffuse pustular dermatitis, growth of the ameloblastoma on the hard palate, and various degenerative and aging changes were noted on necropsy at that time. This is the first report of an ameloblastoma in a member of the Ursidae family.

Estimation of activity coefficients for aqueous organic redox flow batteries: Theoretical basis and equations.

The field of aqueous organic redox flow batteries (AORFBs) has been developing fast in recent years, and many chemistries are starting to emerge as serious contenders for grid-scale storage. The industrial development of these systems would greatly benefit from accurate physics-based models, allowing to optimize battery operation and design. Many authors in the field of flow battery modeling have brought evidence that the dilute solution hypothesis (the assumption that aqueous electrolytes behave ideally) does not hold for these systems and that calculating cell voltage or chemical potentials through concentrations rather than activities, while serviceable, may become insufficient when greater accuracy is required. This article aims to provide the theoretical basis for calculating activity coefficients of aqueous organic electrolytes used in AORFBs to provide tools to predict the concentrated behavior of aqueous electrolytes, thereby improving the accuracy of physics-based models for flow batteries.

Evaluation of the role of the cyclooxygenase signaling pathway during inflammation in skin and muscle tissues of ball pythons (Python regius).

OBJECTIVE To determine degrees of production of cyclooxygenase (COX)-1 and -2 and other mediators of inflammation in noninflamed and inflamed skin and muscle tissues in ball pythons (Python regius). ANIMALS 6 healthy adult male ball pythons. PROCEDURES Biopsy specimens of noninflamed skin and muscle tissue were collected from anesthetized snakes on day 0. A 2-cm skin and muscle incision was then made 5 cm distal to the biopsy sites with a CO2 laser to induce inflammation. On day 7, biopsy specimens of skin and muscle tissues were collected from the incision sites. Inflamed and noninflamed tissue specimens were evaluated for production of COX-1, COX-2, phosphorylated protein kinase B (AKT), total AKT, nuclear factor κ-light-chain-enhancer of activated B cells, phosphorylated extracellular receptor kinases (ERKs) 1 and 2, and total ERK proteins by western blot analysis. Histologic evaluation was performed on H&E-stained tissue sections. RESULTS All biopsy specimens of inflamed skin and muscle tissues had higher histologic inflammation scores than did specimens of noninflamed tissue. Inflamed skin specimens had significantly greater production of COX-1 and phosphorylated ERK than did noninflamed skin specimens. Inflamed muscle specimens had significantly greater production of phosphorylated ERK and phosphorylated AKT, significantly lower production of COX-1, and no difference in production of COX-2, compared with production in noninflamed muscle specimens. CONCLUSIONS AND CLINICAL RELEVANCE Production of COX-1, but not COX-2, was significantly greater in inflamed versus noninflamed skin specimens from ball pythons. Additional research into the reptilian COX signaling pathway is warranted.

PROGRESSIVE SYRINGOHYDROMYELIA AND DEGENERATIVE AXONOPATHY IN A BOBCAT (LYNX RUFUS) FOLLOWING SURGICAL CORRECTION OF A CHIARI-LIKE MALFORMATION.

A 3-yr-old male captive bobcat (Lynx rufus) presented with chronic ataxia and right-sided head tilt. Magnetic resonance imaging (MRI) revealed cerebellar crowding and compression consistent with Chiari-like malformation. The clinical signs did not improve after surgical occipital craniectomy, and 2 mo postoperatively a second MRI showed hydromyelia and continued cerebellar compression. The bobcat was euthanized, and necropsy showed chronic focal cerebellar herniation and chronic multifocal atlanto-occipital joint osteophyte proliferation. Histology confirmed the presence of a thick fibrous membrane along the caudal aspect of the cerebellar vermis, suggestive of postoperative adhesions, and axonal degeneration of the cervical spinal cord, even in sections without a central canal lesion. These lesions appear to have been complications associated with surgical correction of the Chiari-like malformation.

Effect of laser treatment on first-intention incisional wound healing in ball pythons (Python regius).

OBJECTIVE: To evaluate effects of laser treatment on incisional wound healing in ball pythons (Python regius). ANIMALS: 6 healthy adult ball pythons. PROCEDURES: Snakes were sedated, a skin biopsy specimen was collected for histologic examination, and eight 2-cm skin incisions were made in each snake; each incision was closed with staples (day 0). Gross evaluation of all incision sites was performed daily for 30 days, and a wound score was assigned. Four incisions of each snake were treated (5 J/cm(2) and a wavelength of 980 nm on a continuous wave sequence) by use of a class 4 laser once daily for 7 consecutive days; the other 4 incisions were not treated. Two excisional skin biopsy specimens (1 control and 1 treatment) were collected from each snake on days 2, 7, 14, and 30 and evaluated microscopically. Scores were assigned for total inflammation, degree of fibrosis, and collagen maturity. Generalized linear models were used to investigate the effect of treatment on each variable. RESULTS: Wound scores for laser-treated incisions were significantly better than scores for control incisions on day 2 but not at other time points. There were no significant differences in necrosis, fibroplasia, inflammation, granuloma formation, or bacterial contamination between control and treatment groups. Collagen maturity was significantly better for the laser-treated incisions on day 14. CONCLUSIONS AND CLINICAL RELEVANCE: Laser treatment resulted in a significant increase in collagen maturity at day 14 but did not otherwise significantly improve healing of skin incisions.

Pharmacokinetics of cefovecin (Convenia) in white bamboo sharks (Chiloscyllium plagiosum) and Atlantic horseshoe crabs (Limulus polyphemus).

Cefovecin was administered to six healthy adult white bamboo sharks (Chiloscyllium plagiosum) and six healthy adult Atlantic horseshoe crabs (Limulus polyphemus) to determine its pharmacokinetics in these species. A single dose of cefovecin at 8 mg/kg was administered subcutaneously in the epaxial region of the bamboo sharks and in the proximal articulation of the lateral leg of the horseshoe crabs. Blood and hemolymph samples were collected at various time points from bamboo sharks and Atlantic horseshoe crabs. High performance liquid chromatography was performed to determine plasma levels of cefovecin. The terminal halflife of cefovecin in Atlantic horseshoe crabs was 37.70 +/- 9.04 hr and in white bamboo sharks was 2.02 +/- 4.62 hr. Cefovecin concentrations were detected for 4 days in white bamboo sharks and for 14 days in Atlantic horseshoe crabs. No adverse effects associated with cefovecin administration were seen in either species.

Development of a method for the determination of cefovecin in plasma by HPLC.

A simple high-performance liquid chromatography method for the determination of cefovecin in small volume plasma has been developed. Following solid-phase extraction using Oasis HLB cartridges, samples were separated by reverse-phase high-performance liquid chromatography on an XBridge C8 (3.5 µm) 4.6 × 250 mm column and quantified using ultraviolet detection at 280 nm. The mobile phase was a mixture of 10 mm ammonium acetate (pH 3.5) and acetonitrile (89:11), with a flow rate of 0.85 mL/min. The standard curve ranged from 0.1 to 200 µg/mL. Intra- and Inter-assay variability for cefovecin was <10%, and the average recovery was >90%. The lower limit of quantitation was 0.1 µg/mL. This method was successfully applied to the analysis of cefovecin samples at our institution. This is also the first fully validated method with an internal standard that does not use mass spectrometry.

Branchial Cyst With Carcinoma in an Umbrella Cockatoo (Cacatua alba).

A 16-year-old female umbrella cockatoo (Cacatua alba) was presented for a fluctuant, right-sided cervical mass that extended from the caudolateral edge of the right mandible to the coelomic inlet. Results of initial diagnostic tests were consistent with a cystic mass containing hemorrhage. Surgical exploration and removal of the mass was done, but because the hyoid apparatus was incorporated in the base of the cyst, complete surgical excision was not possible. Histopathologic results were consistent with a branchial cyst with carcinoma. Five months after surgery, the cockatoo exhibited intermittent periorbital swelling and epistaxis, and cytologic results of a fluid aspirate from the right infraorbital sinus were consistent with carcinoma. Results of magnetic resonance imaging revealed extensive abnormal T2 and short-tau inversion-recovery hyperintense tissue associated with the right side of the head and neck, infiltrating between muscle planes and extending into the right retro-orbital tissue and nasal cavity. At 7 months after surgery, the bird was severely dyspneic and was euthanatized. To our knowledge, this is the first report describing the diagnosis, management, and histologic characteristics associated with a branchial cyst with carcinoma in an animal.

Diagnosis and treatment of a dermal malignant melanoma in an African lion (Panthera leo).

A 13-yr-old intact male African lion (Panthera leo) presented with a 4-mo history of left maxillary lip swelling. On physical examination, a 10-cm-diameter, ulcerated, round, firm, and pigmented mass at the level of the left maxillary canine tooth was noticed. All other organ systems examined were within normal limits. Multiple biopsies of the mass were collected and fixed in 10% neutral buffered formalin. Histopathologic evaluation of the biopsies revealed a malignant dermal melanoma. Hematologic and plasma biochemical parameters were within normal reference ranges. Thoracic radiographs taken 3 days following initial presentation showed no evidence of metastasis of the tumor. Computed tomography of the skull and neck was performed to evaluate local tumor invasion and to plan for hypofractionated radiation therapy. Therapy included four weekly treatments of 8 gray external-beam hypofractionated radiation and four bimonthly immunotherapy treatments. Following this treatment regime, the tumor size was reduced by 50%, and surgical excision was performed. No major side effects associated with radiation or immunotherapy were seen. Six months after diagnosis, hematologic and plasma biochemical parameters were within normal limits, thoracic radiographs showed no evidence of metastasis, and the lion showed no clinical signs of disease. The lion will continue to receive immunotherapy every 6 mo for the rest of its life. To the authors' knowledge, this is the first report of a successful treatment of a malignant dermal melanoma with external-beam hypofractionated radiation, immunotherapy, and surgical excision in an African lion.

Diagnosis and treatment of a pharyngeal squamous cell carcinoma in a Madagascar ground boa (Boa madagascariensis).

A 15-yr-old female Madagascar ground boa (Boa madagascariensis) presented with a history of anorexia, wheezing, and occasional open-mouth breathing. On oral examination, a firm, caseous mass was noted in the right caudoventral pharyngeal region, which was confirmed as a carcinoma on incisional biopsy. Advanced imaging (computed tomography and magnetic resonance imaging) was performed to evaluate local tumor invasion and to plan for palliative radiation therapy. However, following the second treatment (10 Gy), the mass had increased in size, and the snake was euthanatized. Radiation-associated vasculitis was noted within the soft tissues surrounding the mass and within muscles and the lung, which was verified on histopathology. The squamous cell carcinoma of the snake in this report was resistant to palliative radiation therapy.

Comparison of first-intention healing of carbon dioxide laser, 4.0-MHz radiosurgery, and scalpel incisions in ball pythons (Python regius).

OBJECTIVE: To evaluate first-intention healing of CO(2) laser, 4.0-MHz radiowave radiosurgery (RWRS), and scalpel incisions in ball pythons (Python regius). ANIMALS: 6 healthy adult ball pythons. PROCEDURES: A skin biopsy sample was collected, and 2-cm skin incisions (4/modality) were made in each snake under anesthesia and closed with surgical staples on day 0. Incision sites were grossly evaluated and scored daily. One skin biopsy sample per incision type per snake was obtained on days 2, 7, 14, and 30. Necrotic and fibroplastic tissue was measured in histologic sections; samples were assessed and scored for total inflammation, histologic response (based on the measurement of necrotic and fibroplastic tissues and total inflammation score), and other variables. Frequency distributions of gross and histologic variables associated with wound healing were calculated. RESULTS: Gross wound scores were significantly greater (indicating greater separation of wound edges) for laser incisions than for RWRS and scalpel incisions at all evaluated time points. Necrosis was significantly greater in laser and RWRS incisions than in scalpel incision sites on days 2 and 14 and days 2 and 7, respectively; fibroplasia was significantly greater in laser than in scalpel incision sites on day 30. Histologic response scores were significantly lower for scalpel than for other incision modalities on days 2, 14, and 30. CONCLUSIONS AND CLINICAL RELEVANCE: In snakes, skin incisions made with a scalpel generally had less necrotic tissue than did CO(2) laser and RWRS incisions. Comparison of the 3 modalities on the basis of histologic response scores indicated that use of a scalpel was preferable, followed by RWRS and then laser.

Cefovecin (Convenia) for the treatment of septic peritonitis in a female lion (Panthera leo).

An 8-yr-old intact female African lion (Panthera leo) presented with a 3-day history of lethargy, anorexia, and vomiting. Hematologic and biochemical abnormalities included a leukocytosis, 41,700/microl (4,700-15,300) with a neutrophilia (37,530/microl; 2,000-9,200) and a left shift (1,250/microl bands; 0-300), and mild hypokalemia of 2.1 mEq/L (2.8-4.8). Abdominal radiographs revealed evidence of intestinal ileus, peritonitis, and the presence of effusion. An exploratory laparotomy was performed, and septic peritonitis due to a pyometra was diagnosed. The lion was treated with an ovariohysterectomy, abdominal lavage, fluid therapy, and a subcutaneous injection of cefovecin. The lion recovered, and clinical signs associated with septic peritonitis resolved within 36 hr. It was returned to conspecifics 3 wk later. Three months postoperatively, the lion showed no residual signs of septic peritonitis.

Selected cardiopulmonary values and baroreceptor reflex in conscious green iguanas (Iguana iguana).

OBJECTIVE: To determine selected cardiopulmonary values and baroreceptor response in conscious green iguanas (Iguana iguana) and to evaluate the use of blood gas analysis and pulse oximetry in this species. ANIMALS: 15 healthy juvenile green iguanas. PROCEDURES: Baseline cardiopulmonary values were determined in 15 conscious iguanas breathing room air. Effects of 100% O(2) inspiration were also measured (n = 6), and the baroreceptor reflex was characterized by exponential sigmoidal curve fitting analysis. RESULTS: Conscious iguanas had a mean ± SD resting heart rate of 52 ± 8 beats/min, respiratory rate of 28 ± 6 breaths/min, and systolic, mean, and diastolic arterial blood pressures of 69 ± 10 mm Hg, 62 ± 12 mm Hg, and 56 ± 13 mm Hg, respectively. Mean arterial pH at 37°C was 7.29 ± 0.11, PaO(2) was 81 ± 10 mm Hg, and PaCO(2) was 42 ± 9 mm Hg; corrected for a body temperature of 30°C, mean arterial pH at 37°C was 7.382 ±0.12, PaO(2) was 54 ± 15 mm Hg, and PaCO(2) was 32 ± 7 mm Hg. Inspiration of 100% O(2) did not change heart and respiratory rates but increased PaO(2) to 486 ± 105 mm Hg (corrected value, 437 ± 96 mm Hg). A baroreceptor reflex was evident, with mean heart rates ranging from 30 ± 3 beats/min to 63 ± 5 beats/min and mean arterial blood pressures ranging from 42 ± 3 mm Hg to 58 ± 3 mm Hg. CONCLUSIONS AND CLINICAL RELEVANCE: This study provided needed information on cardiopulmonary values in healthy green iguanas, the application and limitation of arterial and venous blood gas analysis, and the accuracy of pulse oximetry.

PCR prevalence of Ranavirus in free-ranging eastern box turtles (Terrapene carolina carolina) at rehabilitation centers in three southeastern US states.

Ranaviruses (genus Ranavirus) have been observed in disease epidemics and mass mortality events in free-ranging amphibian, turtle, and tortoise populations worldwide. Infection is highly fatal in turtles, and the potential impact on endangered populations could be devastating. Our objectives were to determine the prevalence of ranavirus DNA in blood and oral swabs, report associated clinical signs of infection, and determine spatial distribution of infected turtles. Blood and oral swabs were taken from 140 eastern box turtles (Terrapene carolina carolina) that were presented to the wildlife centers at the University of Tennessee (UT; n=39), Wildlife Center of Virginia (WCV; n=34), and North Carolina State University (NCSU; n=36), as well as a free-ranging nonrehabilitation population near Oak Ridge, Tennessee (OR; n=39) March-November 2007. Samples were evaluated for ranavirus infection using polymerase chain reaction (PCR) targeting a conserved portion of the major capsid protein. Two turtles, one from UT and one from NCSU, had evidence of ranavirus infection; sequences of PCR products were 100% homologous to Frog Virus 3. Prevalence of ranavirus DNA in blood was 3, 0, 3, and 0% for UT, WCV, NCSU, and OR, respectively. Prevalence in oral swab samples was 3, 0, and 0% for UT, WCV, and NCSU, respectively. Wildlife centers may be useful in detection of Ranavirus infection and may serve as a useful early monitoring point for regional disease outbreaks.

Respiratory medicine of reptiles.

Noninfectious and infectious causes have been implicated in the development of respiratory tract disease in reptiles. Treatment modalities in reptiles have to account for species differences in response to therapeutic agents as well as interpretation of diagnostic findings. Data on effective drugs and dosages for the treatment of respiratory diseases are often lacking in reptiles. Recently, advances have been made on the application of advanced imaging modalities, especially computed tomography for the diagnosis and treatment monitoring of reptiles. This article describes common infectious and noninfectious causes of respiratory disease in reptiles, including diagnostic and therapeutic regimen.

The effects of a probiotic on blood urea nitrogen and creatinine concentrations in large felids.

Chronic kidney disease is a common finding in older captive exotic felids. The purpose of this study was to evaluate the effectiveness of a probiotic to reduce blood urea nitrogen and creatinine in large felids. Fifteen adult, large felids (6 tigers [Panthera tigris], 5 lions [Panthera leo], 3 cougars [Puma concolor], and 1 leopard [Panthera pardus]) were administered a probiotic twice daily after a baseline complete blood cell count and plasma chemistry panel was obtained. Plasma chemistry values were rechecked at 2 mo (n = 14) and 6 mo (n = 9). There was no significant change in blood urea nitrogen over time; however, there was a significant change in creatinine over time (P = 0.04). Creatinine concentration decreased significantly between 2 and 6 mo (P = 0.02), and a decrease was seen between 0 and 6 mo, but this change was not significant (P = 0.05). There was no significant difference noted for creatinine concentration between 0 and 2 mo (P = 0.35). This probiotic may be helpful in large felids with elevated creatinine concentrations because of chronic kidney disease; however, further studies are warranted.

The effects of short- and long-term hypoxia on hemolymph gas values in the American horseshoe crab (Limulus polyphemus) using a point-of-care analyzer.

Hemolymph gas parameters were evaluated using a point-of-care analyzer in healthy American horseshoe crabs (Limulus polyphemus) at rest and after short- and long-term removal from water. Baseline vascular pH, partial pressure of oxygen (PO2), partial pressure of carbon dioxide, bicarbonate, base excess, total carbon dioxide, and lactate concentrations were determined from hemolymph samples collected from 10 horseshoe crabs (group 1) submerged in water and were compared with values after removal from water for 5 min, and after recovery in water for 10 min and for longer than 60 min (range, 61-221 min). Hemolymph gas parameters were also determined in 12 horseshoe crabs (group 2) after shipment out of water for 24 hr and were compared with values obtained from group 1 animals. Baseline hemolymph gas values of the American horseshoe crab are within range for other aquatic vertebrates. After removal from water for 5 min, all group 1 crabs developed severe hypoxia, with PO2 levels falling below the detectable limit of the analyzer. Group 2 crabs had pronounced respiratory acidosis, and their PO2 values were significantly below baseline values of group 1 animals.

Comparison of chemistry analytes between 2 portable, commercially available analyzers and a conventional laboratory analyzer in reptiles.

BACKGROUND: Advantages of handheld and small bench-top biochemical analyzers include requirements for smaller sample volume and practicality for use in the field or in practices, but little has been published on the performance of these instruments compared with standard reference methods in analysis of reptilian blood. OBJECTIVE: The aim of this study was to compare reptilian blood biochemical values obtained using the Abaxis VetScan Classic bench-top analyzer and a Heska i-STAT handheld analyzer with values obtained using a Roche Hitachi 911 chemical analyzer. METHODS: Reptiles, including 14 bearded dragons (Pogona vitticeps), 4 blue-tongued skinks (Tiliqua gigas), 8 Burmese star tortoises (Geochelone platynota), 10 Indian star tortoises (Geochelone elegans), 5 red-tailed boas (Boa constrictor), and 5 Northern pine snakes (Pituophis melanoleucus melanoleucus), were manually restrained, and a single blood sample was obtained and divided for analysis. Results for concentrations of albumin, bile acids, calcium, glucose, phosphates, potassium, sodium, total protein, and uric acid and activities of aspartate aminotransferase and creatine kinase obtained from the VetScan Classic and Hitachi 911 were compared. Results for concentrations of chloride, glucose, potassium, and sodium obtained from the i-STAT and Hitachi 911 were compared. RESULTS: Compared with results from the Hitachi 911, those from the VetScan Classic and i-STAT had variable correlations, and constant or proportional bias was found for many analytes. Bile acid data could not be evaluated because results for 44 of 45 samples fell below the lower linearity limit of the VetScan Classic. CONCLUSIONS: Although the 2 portable instruments might provide measurements with clinical utility, there were significant differences compared with the reference analyzer, and development of analyzer-specific reference intervals is recommended.

Pyometra in captive large felids: a review of eleven cases.

Eleven cases of pyometra were diagnosed in a captive exotic felid collection over 3 yr in seven African lions (Panthera leo), two tigers (P. tigris), one liger (lion-tiger crossbreed), and one leopard (P. pardus). Clinical signs included anorexia, lethargy, vulvar discharge, and vomiting. Diagnosis was based on clinical signs, complete blood cell counts, plasma biochemistry and electrolyte values, radiographs, and abdominal ultrasonography. The most common findings on complete blood count and biochemistry profiles were leukocytosis (>15,000/microL) and hyperproteinemia (>8.2 g/dL) due to increased globulins. Abdominal radiographic findings were largely nonspecific, but ultrasonography routinely showed a distended, fluid-filled uterus. Each case was treated with ovariohysterectomy and systemic antibiotic therapy. Lions were shown to be at an increased risk for developing pyometra compared with other species. Pyometra should be considered as a differential diagnosis in anorexic or lethargic intact female large felids, and ovariohysterectomy may be warranted in nonbreeding female lions.

Diagnosis and surgical treatment of a Chiari I-like malformation in an African lion (Panthera leo).

A 13-mo-old intact male African lion (Panthera leo) presented with a 3-mo history of lethargy, ventral flexion of the neck, abnormal vocalization, and ataxia. Hemogram and serum biochemistries were within normal limits except for the presence of hypokalemia (2.7 mEq/L) and hypochloridemia (108 mEq/L). When no improvement was noted with oral potassium gluconate supplementation, a computed tomography scan of the brain and skull was performed, and no abnormalities were noted. However, magnetic resonance imaging detected occipital bone thickening, crowding of the caudal cranial fossa with cerebellar compression and herniation, and cervical syringohydromyelia, which was consistent with a Chiari I-like malformation. Foramen magnum decompression was performed to relieve the compression of the cerebellum. The animal recovered well with subsequent resolution of clinical signs. Hypovitaminosis A has been proposed previously as the underlying etiology for this malformation in lions with similar clinical presentations. This lion's serum and liver vitamin A concentrations were low (100 ng/ml and 25.31 microg/g, respectively) compared to concentrations reported for domestic carnivores and support hypovitaminosis A as the underlying cause of this animal's Chiari I-like malformation.