THE MANAGEMENT OF LYMPHOPROLIFERATIVE NEOPLASIA IN FOUR NORTHERN SEA OTTERS (ENHYDRA LUTRIS KENYONI).

Lymphoproliferative neoplasia has been reported in both free-ranging sea otters and those in managed care, but little information is available on the management of this neoplastic disease in this species. This case series describes clinical lymphoma in four northern sea otters (Enhydra lutris kenyoni) in managed care. Two otters presented with Stage 5 lymphoma with evidence of hematologic spread resulting in leukemia. Two additional otters presented with Stage 3 disease. Immunophenotypes in these cases included disseminated large B-cell lymphoma and lymphoblastic lymphoma of potential T-cell origin. Cases were managed with multiagent chemotherapy protocols including prednisone, L-asparaginase, cyclophosphamide, vincristine, cytosine arabinoside, lomustine, and doxorubicin. Unique approaches included the use of a vascular access port in one case and development of an autologous vaccine in another. Survival time ranged from 81 to 409 days. Diagnosis, staging, and treatment with multiagent protocols is recommended for the management of lymphoma in sea otters.

THE PHARMACOKINETICS AND PHARMACODYNAMICS OF ORAL PONAZURIL IN THE TREATMENT OF SYSTEMIC ISOSPOROSIS IN PASSERINE BIRDS.

Systemic isosporosis, previously atoxoplasmosis, is a significant cause of mortality in juvenile passerine birds. Recommended treatment regimens are empiric and vary in efficacy. The goal of this study was to determine the pharmacokinetics and pharmacodynamics of ponazuril for treatment of systemic isosporosis. Ponazuril, diluted with water to create an oral suspension (50 mg/ml), was administered (100 mg/kg) to 72 European starlings (Sturnus vulgaris) by a single dose via direct oral gavage (n = 24), a single dose injected into superworm larvae (Zophobas morio; n = 24), or a daily dose mixed with commercial dog food to top-dress feed for 5 d (n = 24). Peak plasma concentrations were 5.84, 2.46, and 9.13 µg/ml for the direct gavage, injected larvae, and top-dressed feed groups, respectively. With repeated dosing, mean plasma concentrations from the top-dressed feed group were maintained between 8.12 to 13.11 µg/ml. Results suggested ponazuril at a dosage of 100 mg/kg administered via direct gavage or top-dressed feed, but not via injected larvae, would exceed the concentrations needed to inhibit merogony of other apicomplexan parasites in cell culture (5 µg/ml). To assess the pharmacodynamics of this dose, seven passerine birds, red-vented bulbuls (Pycnonotus cafer; n = 2), blue-grey tanager (Thraupis episcopus; n = 1), and red-capped cardinals (Paroaria gularis; n = 4), were identified as shedders of systemic Isospora spp. via fecal qPCR. Birds were then treated with ponazuril (100 mg/kg) daily on top-dressed feed for 14 d. Fecal shedding was assessed via qPCR for 6 wk from the initiation of treatment. Treatment was associated with reduction in proportions of fecal shedding during the treatment period and the week following treatment, but shedding resumed in all birds by the end of sampling. Results support that treatment of breeding birds with 100 mg/kg ponazuril could reduce the shedding of active oocysts and decrease risk of clinical infection in susceptible juveniles.

THE EFFECTS OF PROCEDURE DURATION AND ATIPAMEZOLE ADMINISTRATION ON HYPERKALEMIA IN TIGERS (PANTHERA TIGRIS) AND LIONS (PANTHERA LEO) ANESTHETIZED WITH α-2 AGONISTS.

A retrospective analysis of 40 extended (>2 hr) anesthetic events in eight lions (Panthera leo) and 32 tigers (Panthera tigris) was performed using a hierarchical linear growth curve model to assess the effects of anesthetic time, α-2 adrenoreceptor agonist dosages, administration of atipamezole, and biochemical parameters on rising plasma K+ concentrations. Hyperkalemia was first noted at a mean time of 187 min (range: 131-226 min), with time under anesthesia as a statistically significant predictor of K+ concentration (P < 0.0001). A significant two-way interaction between time and atipamezole administration (P = 0.0082) for rising K+ concentrations was demonstrated, indicating that administration of atipamezole can mitigate the rise in K+ concentrations. Administration of atipamezole beyond 150 min of anesthetic time was less effective in reducing K+ concentrations than if administered earlier. Electrocardiographic abnormalities were noted in eight animals, including three hyperkalemic individuals. Lions developed significantly greater plasma K+ concentrations than tigers (P = 0.0009) during anesthesia. No biochemical parameter was identified as a significant indicator of which individuals will develop hyperkalemia. Clinicians anesthetizing any large nondomestic felid should monitor electrolytes regularly during anesthetic events; consider early, partial- to full-dose reversal of α-2 agonists; and be prepared to correct potentially life-threatening electrocardiographic abnormalities resulting from hyperkalemia.

REVIEW OF ANESTHETIC PROTOCOLS IN ANDEAN BEARS (TREMARCTOS ORNATUS), SLOTH BEARS (MELURSUS URSINUS), AND GIANT PANDAS (AILUROPODA MELANOLEUCA) AT THE SMITHSONIAN INSTITUTION'S NATIONAL ZOOLOGICAL PARK, 1995-2016.

A review of anesthetic procedures used in Andean bears (Tremarctos ornatus), sloth bears (Melursus ursinus), and giant pandas (Ailuropoda melanoleuca) housed at the Smithsonian Institution's National Zoological Park (NZP) from 1995 to 2016 was performed. A total of 146 anesthetic procedures (55 procedures on 12 Andean bears, 38 procedures on nine sloth bears, and 53 procedures on five giant pandas) occurred at NZP during this time frame. Induction protocols involved some combination of ketamine (K; n = 121), tiletamine-zolazepam (TZ; n = 91), medetomidine (M; n = 67), xylazine (X; n = 42), midazolam (Mid; n = 9), and butorphanol (B; n = 1). The most commonly used protocols were TZKM for both Andean bears (n = 29) and sloth bears (n = 12), and KX in giant pandas (n = 17). Supplemental injections of K, TZ, Mid, or M were required to complete inductions in 66 cases (45%). Anesthetic maintenance was most often completed with isoflurane, ketamine, or propofol. The most commonly reported complications included perianesthetic emesis (n = 47), ptyalism (n = 16), and seizure-like activity (n = 11). The most frequent physiologic findings included low pulse oximetry values (n = 95), bradycardia (n = 95), hypothermia (n = 74), and hypertension (n = 55). Dose ranges, induction, and recovery times, supplementation and complication rates, and physiologic values are reported for each protocol by species.

Pathology of the Bearded Dragon (Pogona vitticeps): a Retrospective Analysis of 36 Cases.

The bearded dragon (Pogona vitticeps) is a common species in the pet reptile trade and in zoological collections. Despite this, only a few reviews detailing common causes of mortality have been published. The goal of this retrospective study was to compile information related to the presence and prevalence of various diseases in bearded dragons in several private and one zoological collection. Findings from 36 animals, necropsied over a 20-year period were categorized on the basis of the cause of death or euthanasia and the organ system affected. Multiple contributors to death were identified in a subset of animals (n = 12; 33.33%) and were counted in more than one category. The most common contributors to death by category were inflammatory (infectious or non-infectious) diseases (n = 25; 69.44%), followed by chronic/degenerative diseases (n = 17; 47.22%). Diseases or conditions that were systemic, or affected the hepatobiliary system, were the most commonly implicated in death. The most frequent histological findings included hepatic fatty change, renal tubular epithelial pigmentation and the presence of faveolar hyaline-like material. Although Chi square testing did not reveal an association between these common findings and comorbidities, a statistically significant association was found between chronic/degenerative causes of death and renal tubular epithelial pigment. Chi square testing of categorical variables, including contributors to death, primary organ(s) affected, sex, age class and institution, identified statistically significant associations between males and chronic/degenerative disease (P = 0.043) and inflammatory contributors to death and private collection animals (P = 0.039). Death due to inflammatory contributors was significantly higher in the 1-5-year-old and >5-year-old age classes (P = 0.02).

Single-dose pharmacokinetics of orally administered terbinafine in bearded dragons (Pogona vitticeps) and the antifungal susceptibility patterns of Nannizziopsis guarroi.

OBJECTIVE: To identify the antifungal susceptibility of Nanniziopsis guarroi isolates and to evaluate the single-dose pharmacokinetics of orally administered terbinafine in bearded dragons. ANIMALS: 8 healthy adult bearded dragons. PROCEDURES: 4 isolates of N guarroi were tested for antifungal susceptibility. A compounded oral solution of terbinafine (25 mg/mL [20 mg/kg]) was given before blood (0.2 mL) was drawn from the ventral tail vein at 0, 4, 8, 12, 24, 48, 72, and 96 hours after administration. Plasma terbinafine concentrations were measured with high-performance liquid chromatography. RESULTS: The antifungal minimum inhibitory concentrations against N guarroi isolates ranged from 4,000 to > 64,000 ng/mL for fluconazole, 125 to 2,000 ng/mL for itraconazole, 125 to 2,000 ng/mL for ketoconazole, 125 to 1,000 ng/mL for posaconazole, 60 to 250 ng/mL for voriconazole, and 15 to 30 ng/mL for terbinafine. The mean ± SD peak plasma terbinafine concentration in bearded dragons was 435 ± 338 ng/mL at 13 ± 4.66 hours after administration. Plasma concentrations remained > 30 ng/mL for > 24 hours in all bearded dragons and for > 48 hours in 6 of 8 bearded dragons. Mean ± SD terminal half-life following oral administration was 21.2 ± 12.40 hours. CLINICAL RELEVANCE: Antifungal susceptibility data are available for use in clinical decision making. Results indicated that administration of terbinafine (20 mg/kg, PO, q 24 to 48 h) in bearded dragons may be appropriate for the treatment of dermatomycoses caused by N guarroi. Clinical studies are needed to determine the efficacy of such treatment.

Hematology of Free-ranging and Managed Texas Horned Lizards ( Phrynosoma cornutum).

The Texas horned lizard ( Phrynosoma cornutum) is a threatened species in Texas, US (federal category C2). Causes for population declines in this species are likely multiple. Disease and health assessments using traditional methods, including hematology, have been minimally studied in Phrynosoma spp. Apparently healthy, free-ranging Texas horned lizard from four locations in Texas ( n=53) and captive Texas horned lizards maintained at the Fort Worth Zoo ( n=16) were sampled to establish hematologic reference intervals. Within the populations studied, total leukocyte, heterophil, and eosinophil counts were higher in managed compared to free-ranging lizards. Leukocyte and heterophil counts of all lizards were lower during the ovipositional months of June and July.