Tail base aneurysm in an inland bearded dragon (Pogona vitticeps)

In bearded dragons, aneurysms are most commonly observed on the head and neck and in the cranial coelom. A nine-year-old male bearded dragon (Pogona vitticeps) was presented for a ventral tail base swelling. Aspiration yielded frank blood, and Doppler ultrasonography confirmed an aneurysm by demonstrating pulsatile jets into the lumen. Three months later, the animal presented for acute regurgitation and tenesmus. Coelomic ultrasound showed a distended stomach and pyloroduodenal intussusception. An exploratory coeliotomy revealed a tortuous and distended ventral abdominal vein and mesenteric vasculature. The colon and cecum were markedly distended, and intracoelomic blood clots were discovered. Euthanasia was performed. Necropsy revealed a tail base aneurysm, presumably arterial. The walls of the aneurysm exhibited osseous metaplasia and smooth muscle replacement by fibrous connective tissue with no infectious organisms. This case report provides information on a differential diagnosis for tail base swellings in bearded dragons.     

Granulomatous osteomyelitis associated with atypical mycobacteriosis in a bearded dragon (Pogona vitticeps).

The zoonotic potential of Mycobacterium spp has been well documented and has been implicated in cutaneous and subcutaneous nodular disease in humans. Treatment of the infected reptiles is often not recommended, because of the zoonotic potential. Moreover, the often-advanced nature of the disease when diagnosed, the lengthy and expensive treatment regimens, and lack of a reported successful treatment regimen for reptiles usually warrant euthanasia in these patients. Strict attention must be paid to cage hygiene and sanitation to minimize exposure and eliminate the organisms.     

Chemotherapeutic treatment for leukemia in a bearded dragon (Pogona vitticeps)

A 4.5-yr-old, captive-bred, male bearded dragon (Pogona vitticeps) presented for lethargy, anorexia, and increased mucoid salivation with upper respiratory clicks. Diagnostics were declined and the bearded dragon was prescribed ceftazidime 20 mg/kg i.m. q 72 hr. The patient presented again 1 wk later with a marked monocytosis, heterophilia, and lymphocytosis, and a clinical diagnosis of chronic monocytic leukemia was made. Chemotherapy with cytosine arabinoside (100 mg/m2 over 48 hr i.v.) was initiated. Forty-four hours into the treatment the dragon became acutely unresponsive and died within 1 hr. Adverse effects as a result of i.v. cytosine arabinoside therapy were not identified despite previous reports suggestive that the drug induces renal failure.     

Diagnosis and treatment of a periocular myxosarcoma in a bearded dragon (Pogona vitticeps)

A 5-year-old male Australian bearded dragon (Pogona vitticeps) was presented with a 2-month history of a periocular mass. The clinical evaluation included a physical examination, hematology, biochemistry, and radiographs. The mass was treated surgically and diagnosed as myxosarcoma. Strontium-90 plesiotherapy was attempted, but the mass recurred 5 mo later.     

Dermatomycosis in a pet inland bearded dragon (Pogona vitticeps) caused by a Chrysosporium species related to Nannizziopsis vriesii

A Chrysosporium sp. related to Nannizziopsis vriesii was isolated in pure culture from squames and biopsies of facial lesions in a pet inland bearded dragon ( Pogona vitticeps ) in Spain. The presence in histological sections of morphologically consistent fungal elements strongly incriminates this fungus as the aetiological agent of infection. Lesions regressed following treatment with oral ketoconazole and topical chlorhexidine and terbinafine until the lizard was lost to follow up 1 month later. The ITS-5.8S rRNA gene of the isolate was sequenced and a search on the GenBank database revealed a high match with the sequences of two Chrysosporium sp. strains recently isolated from green iguanas ( Iguana iguana ) with dermatomycosis, also in Spain. Phylogenetic analysis of the sequences revealed that all these strains are related to N. vriesii . This is the first report of dermatomycoses caused by a Chrysosporium species related to N. vriesii in a bearded dragon outside North America.     

Evaluation of neuraxial anesthesia in bearded dragons (Pogona vitticeps)

Objective

To assess the feasibility, success rate, onset, duration and extent of motor/sensory block following intrathecal injection of lidocaine in bearded dragons (Pogona vitticeps).

Devriesea agamarum causes dermatitis in bearded dragons (Pogona vitticeps)

Devriesea agamarum is frequently isolated from dermatitis in lizards, notably from cheilitis in spiny tailed lizards (genus Uromastyx). It was the aim of the present study to assess the role of this bacterium as a causative agent of dermatitis by fulfilling Koch's postulates. First, its association with diseased lizards was demonstrated. The bacterium was isolated from several, mainly desert dwelling squamate species showing symptoms of dermatitis and/or septicaemia. The affected lizards mainly belonged to the family of the Agamidae (genera Pogona, Uromastyx, Agama) and in one case to the Iguanidae (genus Crotaphytus). Secondly, the occurrence of D. agamarum in 66 clinically healthy bearded dragons, 21 clinically healthy Uromastyx species and 40 squamate eggshells was studied. The bacterium was isolated from the oral cavity of 10 bearded dragons but from none of the healthy Uromastyx species. Hence D. agamarum was found to be part of the oral microbiota in Pogona vitticeps. Finally, bearded dragons (P. vitticeps) were experimentally inoculated with D. agamarum by direct application of a bacterial suspension on intact and abraded skin. At the scarified skin of all inoculated lizards, dermatitis was induced from which D. agamarum was re-isolated. In conclusion, D. agamarum is a facultative pathogenic bacterium, able to cause dermatitis in agamid lizards when the integrity of the skin is breached.     

Perception of artificial conspecifics by bearded dragons (Pogona vitticeps)

Artificial animals are increasingly used as conspecific stimuli in animal behavior research. However, researchers often have an incomplete understanding of how the species under study perceives conspecifics, and, hence, which features are needed for a stimulus to be perceived appropriately. To investigate the features that bearded dragons (Pogona vitticeps) attend to, we measured their lateralized eye use when assessing a successive range of stimuli. These ranged through several stages of realism in artificial conspecifics, to see how features such as color, the presence of eyes, body shape and motion influence behavior. We found differences in lateralized eye use depending on the sex of the observing bearded dragon and the artificial conspecific, as well as the artificial conspecific's behavior. Therefore, this approach can inform the design of robotic animals that elicit biologically‐meaningful responses in live animals.     

Evaluation of neuraxial administration of bupivacaine in bearded dragons (Pogona vitticeps)

ObjectiveTo assess the success rate, onset, duration and extent of motor/sensory block following neuraxial injection of two dosages of bupivacaine in bearded dragons (Pogona vitticeps).Study designProspective, randomized, blinded, crossover experimental study.AnimalsA total of 10 adult bearded dragons (0.3 ± 0.1 kg).MethodsAfter sedation with alfaxalone (15 mg kg^–1 subcutaneously), neuraxial injections were performed with 1 or 2 mg kg^–1 bupivacaine hydrochloride (0.5%, treatments BUP-1 and BUP-2, respectively) in a randomized treatment sequence with a 7 day washout period. If the initial bupivacaine injection was not successful within 10 minutes, a second injection was performed at the same dose. Mechanical stimulation of limbs, 25%, 50%, 75% of the trunk’s length and cloacal tone were assessed.ResultsSuccess rate following the first neuraxial injection was 95%, which increased to 100% after the second injection. Motor/sensory block were noted by 5 minutes after the injection of bupivacaine at either dose. BUP-2 was associated with more cranial spread. The median (range) duration of cloacal tone loss was longer following treatment BUP-2 [120 (75–225) minutes] than followed treatment BUP-1 [83 (25–135) minutes; p = 0.03]. Duration of pelvic limb motor block was comparable between both doses, lasting a median of 68 minutes in both treatments (p = 0.94). There was a transient, not clinically relevant increase from baseline in heart rate in treatment BUP-1 only. No significant difference from baseline in respiratory rate was noted in either treatment; however, two animals in treatment BUP-2 became apneic (10–20 minutes).Conclusions and clinical relevanceBupivacaine (1 mg kg^–1) is recommended for neuraxial anesthesia in bearded dragons. In treatment BUP-2, extensive cranial spread resulted in apnea and motor block of the thoracic limb in several animals; therefore this dose is not recommended.     

Myelogenous leukemia in a bearded dragon (Acanthodraco vitticeps).

A 3-yr-old bearded dragon (Acanthodraco vitticeps) presented with lethargy, a swollen right elbow joint, inability to move its rear limbs normally, and marked leukocytosis. The majority of leukocytes were an abnormal mononuclear lymphoid-type cell with a high nuclear to cytoplasmic ratio, a slightly blue cytoplasm, nuclei with coarsely granular chromatin, and some nuclear clefts. Acute leukemia of lymphoid or myeloid origin was tentatively diagnosed. The abnormal mononuclear leukocyte cell population stained positively for the myeloid cytochemical stains: peroxidase, chloroacetate esterase, and L1-calprotectin. The abnormal cell population of the peripheral blood did not stain with the lymphoid cytochemical stains: alpha-naphthyl butyrate esterase, CD3, and CD79a.