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Frogs are popular exotic pets and research subjects. Manual restraint is routinely used for basic procedures in frogs, including examination and sample collection, but there is little information on its physiologic effects in amphibians. Previous literature suggested that amphibians lack emotional responses and, therefore, consciousness, based upon an inability to elicit stress tachycardia with gentle handling. To determine if manual restraint results in a stress tachycardia in frogs, 10 poison dart frogs (Dendrobates tinctorius) and 8 leopard frogs (Lithobates pipiens) were manually restrained and heart rate (HR) recorded at both the pectoral girdle and pelvic patch using a Doppler flow probe. Frogs were randomly placed in one of two (opaque versus translucent) types of plastic containers for 22 min and HR measured every 2 min through the bottom of the container using the frogs' pelvic patch area. Frogs were then removed from the container, manually restrained again, and HR recorded. Heart rate decreased significantly after the frogs were placed in the containers following manual restraint, and increased significantly for the second restraint period. There were no significant differences in measured HR between anatomic sites (pelvic vs. pectoral) or container types. Contrary to previous descriptions, these results demonstrated that, similar to other mammal and reptile species, frogs demonstrated stress tachycardia during manual restraint, and, therefore, clinicians and researchers should be mindful of induced stress when restraining amphibians. [ABSTRACT FROM AUTHOR]

Blue poison dart frogs (Dendrobates tinctorius azureus) are commonly found in zoological institutions and are becoming popular in the pet trade. Sedation or light anesthesia is required for safe and effective handling of this species. In this study, the effect of subcutaneous administration of alfaxalone at two different doses (20 and 30 mg/kg) was evaluated in juvenile blue poison dart frogs (N = 10) in a prospective, randomized, blinded, crossover study. Heart rate, pulmonic respiratory rate, various reflexes, and behavioral parameters were monitored after drug administration. Both protocols resulted in rapid induction of sedation (median [range]) with loss of righting reflex: 20 mg/kg, 10 (10–20 min) and 30 mg/ kg, 10 (10–10 min). The time (mean ± SD) to return to spontaneous movement (20 mg/kg, 39.6 ± 7.6 min and 30 mg/kg, 54.5 ± 9.9 min; P < 0.01) and full recovery (20 mg/kg, 42.6 ± 8 min and 30 mg/kg, 61.6 ± 9.1 min; P < 0.01) after alfaxalone administration were significantly longer in the 30-mg/kg group. The frogs in both groups continued to remain responsive to tactile stimulation and retained palpebral reflexes. Alfaxalone induced cardiopulmonary depression and periods of apnea at both doses. The subcutaneous administration of 20 and 30 mg/kg alfaxalone resulted in clinically effective sedation in blue poison dart frogs. Sedation levels achieved in this prospective study would be adequate for a variety of noninvasive clinical procedures. [ABSTRACT FROM AUTHOR]

We reviewed necropsy records of 124 Whooping Cranes (Grus americana) recovered following reintroduction of 268 individuals from 2001 to 2016 in the eastern US. Causes of death were determined in 62% (77/124) of cases facilitated by active monitoring that limited decomposition and scavenging artifact. The greatest proportions of mortality were caused by predation (0.468; 95% confidence interval 0.356–0.580; 36/77), collision with power lines or vehicles (0.260; 0.162–0.358; 20/77), and gunshot (0.169; 0.085–0.253; 13/77). Six deaths were attributed to infection (0.078; 0.018–0.138; 6/77), including bacterial and fungal etiologies. Lead analysis of 50 liver samples yielded two results with elevated concentrations (3.65 and 10.97 ppm wet weight), and 10 bone samples from partial carcasses lacking suitable liver tissue resulted in one elevated result (48.82 ppm dry weight). These data indicate that underlying subclinical or clinical lead toxicosis may be a factor in up to 5% of deaths attributed to predation or impact trauma. Brain cholinesterase activity testing indicated no exposure to organophosphate or carbamate pesticides (mean±SD=17.32±2.90 µmol/min/g, 31/71). The causes of death and potential underlying factors summarized in this study constitute the first definitive mortality survey of migratory Whooping Cranes based on a high carcass recovery rate. Causes of death by infectious etiologies remained comparatively rare in this study, and occurred as single cases with no evidence of sustained transmission among reintroduced Whooping Cranes. [ABSTRACT FROM AUTHOR]

CASE DESCRIPTION: A 7-year-old female blue crane (Anthropoides paradiseus) was initially evaluated after it had suddenly developed signs of respiratory distress following aspiration of a rock. Emergency tracheotomy had been performed, and the rock had been removed from the proximal cervical portion of the trachea. Fifty-one days later, the clinical signs had returned and the crane was reevaluated. CLINICAL FINDINGS: On reevaluation, no obvious external abnormalities were appreciated at the previous surgical site and no discharge was observed from the glottis. Computed tomography and tracheoscopy revealed marked tracheal stenosis and architectural collapse of the trachea at the previous surgery site. TREATMENT AND OUTCOME: Tracheal resection and anastomosis was performed to remove the stenotic tracheal segment. Histologic examination of the resected tracheal segment revealed pyogranulomas with intralesional coccobacilli, fungal hyphae consistent with Aspergillus spp, possible parasitic ova, and features suggestive of mild to moderate heterophilic and lymphoplasmacytic tracheitis. The crane was treated with piroxicam, ceftiofur crystalline free acid, terbinafine, and itraconazole. At a follow-up examination 12 weeks later, no abnormalities were appreciated, and the surgical site had completely healed. CLINICAL RELEVANCE: To the authors' knowledge, this is the first reported case of successful tracheal resection and anastomosis in a bird of the order Gruiformes. The surgical approach used for the blue crane may be useful for removal of tracheal foreign bodies in this and other long-necked avian species. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To evaluate SC administration of alfaxalone-midazolam and dexmedetomidine-midazolam for sedation of ball pythons (Python regius). ANIMALS: 12 healthy juvenile ball pythons. PROCEDURES: In a randomized crossover study, each snake was administered a combination of alfaxalone (5 mg/kg [2.3 mg/lb]) and midazolam (0.5 mg/kg [0.23 mg/lb]) and a combination of dexmedetomidine (0.05 mg/kg [0.023 mg/lb]) and midazolam (0.5 mg/kg), SC, with a washout period of at least 7 days between protocols. Respiratory and heart rates and various reflexes and behaviors were assessed and compared between protocols. Forty-five minutes after protocol administration, sedation was reversed by SC administration of flumazenil (0.05 mg/kg) alone or in combination with atipamezole (0.5 mg/kg; dexmedetomidine-midazolam protocol only). Because of difficulties with visual assessment of respiratory effort after sedative administration, the experiment was repeated for a subset of 3 ball pythons, with plethysmography used to assess respiration. RESULTS: Both protocols induced a similar level of moderate sedation with no adverse effects aside from transient apnea. Cardiopulmonary depression was more profound, but time to recovery after reversal was significantly shorter, for the dexmedetomidine-midazolam protocol than for the alfaxalone-midazolam protocol. Plethysmographic findings were consistent with visual observations and suggested that snakes compensated for a decrease in respiratory rate by increasing tidal volume amplitude. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that both protocols induced clinically relevant sedation in ball pythons and should be useful for minor procedures such as venipuncture and diagnostic imaging. However, caution should be used when sedating snakes with compromised cardiopulmonary function. [ABSTRACT FROM AUTHOR]

Blue poison dart frogs (Dendrobates tinctorius azureus) are commonly maintained in zoological institutions and are becoming popular in the pet trade industry. Sedation or light anesthesia is required for safe and effective handling of this species. In this study, the sedative effects of subcutaneously administered alfaxalone–midazolam–dexmedetomidine (AMD) (20, 40, 5 mg/kg, respectively) and ketamine–midazolam–dexmedetomidine (KMD) (100, 40, 5 mg/kg, respectively) were compared in a prospective, randomized, blinded, crossover study in juvenile blue poison dart frogs (n = 10). Both protocols were partially reversed 45 min after administration of either protocol with subcutaneously administered flumazenil (0.05 mg/kg) and atipamezole (50 mg/kg). Heart rate, pulmonic respiratory rate, various reflexes, and behavioral parameters were monitored after drug administration. Both protocols resulted in rapid loss of righting reflex [median (range): AMD, 5 min (5–5 min); KMD, 5 min (5–10 min)]. Time to complete recovery was similar with both protocols (mean ± SD: AMD, 97.5 ± 11.4 min; KMD, 96.5 ± 25.4 min). The AMD protocol resulted in pulmonic respiratory depression, whereas no significant difference in heart rate was found between the two protocols. All frogs were observed eating within 24 hr of chemical restraint. Gastric prolapses occurred in four frogs (AMD 3, KMD 1) that were easily reduced with a cotton-tip application. No other adverse reactions were observed. The results of this study provide two different subcutaneous chemical restraint protocols in juvenile blue poison dart frogs. [ABSTRACT FROM AUTHOR]

CASE DESCRIPTION A 20-year-old female south-central black rhinoceros (Diceros bicornis minor) was evaluated because of an acute onset of CNS deficits. CLINICAL FINDINGS The rhinoceros had no history of illness. Clinical signs included acute lethargy, ataxia, and decreased appetite. Hematologic abnormalities included leukocytosis with neutrophilia and a profound left shift. Results of serum biochemical analysis revealed hypophosphatemia but no other abnormalities. Results of a quantitative PCR assay for West Nile virus and an assay for anti–Neosporum caninum antibodies in serum were negative; the patient was seropositive for multiple Leptospira serovars. TREATMENT AND OUTCOME Antimicrobials and anti-inflammatory agents were administered, but the condition of the rhinoceros worsened overnight; despite treatment with additional anti-inflammatory and antimicrobial agents, IV fluids, and thiamine, it became obtunded and died of respiratory arrest ≤ 24 hours later. Necropsy revealed severe, diffuse, suppurative, and histiocytic meningo-encephalomyelitis involving the cerebrum, cerebellum, and spinal cord. Amebic trophozoites were observed on histologic examination of affected tissue. Infection with Naegleria fowleri was confirmed by results of immuno-histochemical analysis and a multiplex real-time PCR assay. CLINICAL RELEVANCE Findings suggested that south-central black rhinoceros are susceptible to the free-living ameba N fowleri. Ameba-induced meningoencephalomyelitis should be considered as a differential diagnosis for rhinoceros that have an acute onset of neurologic signs. Diagnosis of N fowleri infection in an animal has a profound public health impact because of potential human exposure from the environment and the high fatality rate in people with N fowleri infection. [ABSTRACT FROM AUTHOR]

Historically, wetland toxin exposure studies have relied on single time point samples from stationary sampling devices. Development of passive sampling devices (PSDs) that can be attached to individual animals within wetland habitats has greatly improved in recent years, presenting an innovative sampling technology that can potentially yield individual-specific, quantifiable data about chemical exposure. In this study, silicone based PSDs were attached to the ventral skin of 20 northern leopard frogs ( Lithobates pipiens) with polypropylene sutures after radiotransmitters had been surgically implanted into the coleomic cavity. After a short recovery period, frogs were released back into the wetland habitat where they were acquired. The animals were located daily using radiotelemetry to assess how long PSDs would remain attached in the frogs' natural habitat. After one week, PSDs remained on 18 of the original 20 frogs. At two weeks, 17 frogs were recovered and no PSDs remained attached. Although valuable data can be obtained over a short time period, more research will be necessary to demonstrate the effectiveness of externally attaching silicone PSDs to northern leopard frogs for time periods longer than 1-2 weeks. [ABSTRACT FROM AUTHOR]

Objective To determine if topical ophthalmic diclofenac sodium 0.1% solution alters renal parameters in the domestic chicken, and to determine if the drug is detectable in plasma after topical ophthalmic administration. Animals Thirty healthy domestic chickens. Procedures Over 7 days, six birds were treated unilaterally with one drop of artificial tear solution (group 1), 12 birds were treated unilaterally (group 2) and 12 bilaterally (group 3) with diclofenac sodium 0.1% ophthalmic solution. Treatments were provided every 12 h in all groups. Pre- and post-treatment plasma samples from all birds were evaluated for changes in albumin, total protein, and uric acid. Post-treatment samples of all birds, collected 15 min post-administration, were analyzed by high-performance liquid chromatography with mass spectrometry for diclofenac sodium detection. A randomly selected renal sample from each group was submitted for histopathologic review. Results Changes in pre- and post-treatment plasma albumin were significant ( P < 0.05) in groups 2 and 3, but not for group 1. Pre- and post-treatment changes in total protein and uric acid were not significant for any group. Diclofenac sodium was not detectable (limit of detection = 0.10 ng/mL) in plasma samples from birds in group 1. Post-treatment concentration of diclofenac in group 3 was statistically greater than group 2 ( P = 0.0008). Histopathologic changes did not identify diclofenac-induced acute renal tubular necrosis. Conclusions Ophthalmic diclofenac sodium 0.1% administered topically every 12 h in one or both eyes for 7 days is detectable in systemic circulation in the domestic chicken, but does not cause overt significant changes in plasma uric acid or total protein. [ABSTRACT FROM AUTHOR]

A juvenile, male crested pekin duck ( Anas platyrhynchos f dom) was presented for neurologic signs suggestive of cerebellar disease. Physical examination revealed microphthalmia, erratic head movements, and ataxia. Computed tomography scan of the head and neck regions revealed 2 full-thickness skull-bone defects within the caudal portion of the cranium. The cerebellum appeared to be ventrally compressed by a homogeneous, triangular, fluid-attenuating region (0-10 Hounsfield units). A craniectomy was performed, and a presumed peripheral cerebral cyst was removed with suction and gentle dissection. No postoperative complications occurred, and the patient showed clinical improvement for 5 months after surgery. However, after 5 months, the owners elected euthanasia because of poor prognosis after finding the duck minimally responsive in a water enclosure. At necropsy, a thin-walled, epithelial structure was present in meninges and was adhered to the skull at the presumed surgical site. [ABSTRACT FROM AUTHOR]