26 research outputs found
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Differential Disease Susceptibilities in Experimentally Reptarenavirus-Infected Boa Constrictors and Ball Pythons.
Inclusion body disease (IBD) is an infectious disease originally described in captive snakes. It has traditionally been diagnosed by the presence of large eosinophilic cytoplasmic inclusions and is associated with neurological, gastrointestinal, and lymphoproliferative disorders. Previously, we identified and established a culture system for a novel lineage of arenaviruses isolated from boa constrictors diagnosed with IBD. Although ample circumstantial evidence suggested that these viruses, now known as reptarenaviruses, cause IBD, there has been no formal demonstration of disease causality since their discovery. We therefore conducted a long-term challenge experiment to test the hypothesis that reptarenaviruses cause IBD. We infected boa constrictors and ball pythons by cardiac injection of purified virus. We monitored the progression of viral growth in tissues, blood, and environmental samples. Infection produced dramatically different disease outcomes in snakes of the two species. Ball pythons infected with Golden Gate virus (GoGV) and with another reptarenavirus displayed severe neurological signs within 2 months, and viral replication was detected only in central nervous system tissues. In contrast, GoGV-infected boa constrictors remained free of clinical signs for 2 years, despite high viral loads and the accumulation of large intracellular inclusions in multiple tissues, including the brain. Inflammation was associated with infection in ball pythons but not in boa constrictors. Thus, reptarenavirus infection produces inclusions and inclusion body disease, although inclusions per se are neither necessarily associated with nor required for disease. Although the natural distribution of reptarenaviruses has yet to be described, the different outcomes of infection may reflect differences in geographical origin.IMPORTANCE New DNA sequencing technologies have made it easier than ever to identify the sequences of microorganisms in diseased tissues, i.e., to identify organisms that appear to cause disease, but to be certain that a candidate pathogen actually causes disease, it is necessary to provide additional evidence of causality. We have done this to demonstrate that reptarenaviruses cause inclusion body disease (IBD), a serious transmissible disease of snakes. We infected boa constrictors and ball pythons with purified reptarenavirus. Ball pythons fell ill within 2 months of infection and displayed signs of neurological disease typical of IBD. In contrast, boa constrictors remained healthy over 2 years, despite high levels of virus throughout their bodies. This difference matches previous reports that pythons are more susceptible to IBD than boas and could reflect the possibility that boas are natural hosts of these viruses in the wild
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Post-traumatic ocular lymphoma in three rabbits (Oryctolagus cuniculus)
This report describes post-traumatic ocular lymphoma in 3 companion rabbits; 2 rabbits with unilateral disease and 1 with bilateral disease. Historical findings suggestive of a traumatic event included either external unilateral ocular trauma or bilateral phacoemulsification. Severe corneal changes, presence of an anterior chamber mass(es), low intraocular pressures, and ocular discomfort were noted on ophthalmic examinations. All eyes were treated for variable courses with standard ophthalmic topical medications (antibiotic, anti-inflammatories, and steroid) and systemic anti-inflammatories. Based upon progression of disease, all affected eyes were ultimately enucleated; lenticular capsular rupture and a round cell neoplasm effacing normal structures with variable mitotic indices were noted on histopathology. Neoplastic lymphocytes strongly expressed CD79a via immunohistochemistry and lacked expression for CD3, indicating B lymphocyte lineage and not of T cell lineage. A single animal had evidence of local metastasis to a regional lymph node. Post-traumatic sarcomas have been reported in this species previously, however, these cases are the first reports of this novel round cell variant, named post-traumatic ocular lymphoma due to the B cell lineage confirmed through immunohistochemistry. Clinicians should be aware of this clinical presentation and the possibility of metastasis when evaluating ocular pathology in this species. Copyright 2018 Elsevier Inc. All rights reserved
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Neurological examination in healthy adult inland bearded dragons (Pogona vitticeps).
ObjectiveTo evaluate neurological tests and expected results in inland bearded dragons (Pogona vitticeps) and generate recommendations for bearded dragon-specific neurological examination.Animals26 healthy adult inland bearded dragons.ProceduresA complete neurological examination utilizing tests described in both mammals and reptiles was performed on each lizard, and test feasibility and outcome were recorded.ResultsTests with poor feasibility included oculocardiac reflex (successfully completed in 62% [16/26] of animals) and voluntary ambulation and swallowing by use of a food item (0% [0/26] of animals). Tests with outcomes considered abnormal in mammals but attributable to normal bearded dragon behavior included head position (head tilt present in 12% [3/26]) and head movement (head bob present in 4% [1/26]). Many tests had absent or inconsistent outcomes, including menace response (present in 19% [5/26]), proprioceptive positioning (present in 4% [1/26] in the thoracic limbs and 0% [0/26] in the pelvic limbs), vent reflex (present in 27% [7/26]), and myotatic reflexes (biceps present in 8% [2/26]; patellar, gastrocnemius, and triceps present in 0% [0/26]). Extensor postural thrust was absent in all successfully tested animals, but a novel reflex termed the caudal thoracic extensor reflex was noted instead in all observed animals (100% [21/21]).Clinical relevanceTests with poor feasibility or inconsistent outcomes should have low priority or be excluded from neurological examinations of inland bearded dragons. Normal behaviors should be considered for head position and movement. A bearded dragon-specific neurological examination protocol derived from these findings is described and recommended in order to decrease stress and improve neurolocalization
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Skin diseases in companion guinea pigs (Cavia porcellus): a retrospective study of 293 cases seen at the Veterinary Medical Teaching Hospital, University of California at Davis (1990-2015).
BackgroundGuinea pigs (Cavia porcellus) are popular companion animals with reported skin diseases, but most reports are accessed from textbooks or review articles.Hypothesis/objectivesTo document skin diseases and their prevalence in companion guinea pigs in northern California, USA, and to investigate predilections for the most common conditions over a 25 year period.AnimalsTwo hundred and ninety three guinea pigs from the hospital population met inclusion criteria.MethodsA retrospective study was performed by searching computerized medical records seen at the Veterinary Medical Teaching Hospital (VMTH), School of Veterinary Medicine, University of California from 1 January 1990 to 31 July 2015 using key words relevant to dermatology.ResultsOf the 580 guinea pigs seen at the VMTH, 50% (293) had skin disease. Of the 293 cases, 154 (52%) presented for nondermatological reasons. Guinea pigs with skin disease were significantly older than those without skin disease (P = 0.0002); females with skin disease were more likely to have cystic ovaries (P = 0.0203), although these were not always associated with alopecia. Pododermatitis and infestation with Trixacarus caviae or lice were the most common skin diseases. Ivermectin or selamectin was used for ectoparasite treatment. Abscesses unassociated with pododermatitis were the most common nodules. Benign follicular tumours were the most common neoplasm. Despite the frequent mention of dermatophytosis in the veterinary literature, only two cases of Trichophyton mentagrophytes were diagnosed.Conclusions and clinical importanceCutaneous conditions in companion guinea pigs in the USA are common. Clinicians should include a dermatological examination when examining these rodents regardless of the reason for presentation
Pharmacokinetics after oral and intravenous administration of a single dose of tramadol hydrochloride to Hispaniolan Amazon parrots ( Amazona ventralis
Comparison of hematologic values in blood samples with lithium heparin or dipotassium ethylenediaminetetraacetic acid anticoagulants in Hispaniolan Amazon parrots (Amazona ventralis)
Blood samples were collected from 20 Hispaniolan Amazon parrots (Amazona ventralis) and were divided into tubes that contained dipotassium ethylenediaminetetraacetic acid (K2EDTA) and lithium heparin. Complete blood cell counts were determined in each sample within 2 hours of collection. The level of agreement in results was moderate for plasma protein, packed cell volume (PCV), and leukocyte, monocyte, and lymphocyte counts between the anticoagulants. Plasma protein and PCV values were significantly lower in samples with lithium heparin than in those with K2EDTA, whereas lymphocyte numbers were significantly higher in lithium heparin samples than in K2EDTA samples. The level of agreement was good for the other cell types (heterophils, eosinophils, and basophils) when comparing the different anticoagulants. The poor level of agreement between anticoagulants with the increase in thrombocyte clumping in lithium heparin samples indicates that the use of lithium heparin as anticoagulant may affect thrombocyte count. No negative effects on morphology and staining of blood cells were apparent in smears from heparin samples compared with K2EDTA samples. Within the different values compared, the limits of agreement are small enough to be confident that lithium heparin can be used for routine CBC counts in a clinical setting. The use of the same anticoagulant should be recommended to follow trends within the same patient, especially when considering plasma protein concentration, PCV, and lymphocyte count
Transmission of Lawsonia intracellularis to weanling foals using feces from experimentally infected rabbits
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Peripheral Nerve Sheath Tumor in the Pelvic Limb of a Domestic Rabbit (Oryctolagus cuniculus)
A 3-year-old, 4.0 kg, female, spayed Silver Marten cross rabbit (Oryctolagus cuniculus) was presented for evaluation of a suspected recurring spindle cell sarcoma following primary excision by the referring veterinarian. Physical examination revealed a large subcutaneous mass on the left metatarsus and a fine needle aspirate revealed suspected neoplastic spindle cells. Hematologic evaluation was unremarkable and a computed tomography scan revealed invasion of the mass into skeletal muscles but showed no evidence of metastatic disease. An amputation was performed, after which the patient recovered uneventfully. However, the rabbit was found suddenly dead at time of discharge from unknown cause. Gross, histologic, and immunohistochemical evaluation was performed, which diagnosed a peripheral nerve sheath tumor. To the authors’ knowledge, this is the first detailed case report of a lagomorph peripheral nerve sheath tumor specifically confirmed with immunohistochemistry. Wide surgical excision is considered the treatment of choice and may be combined with radiation therapy. Further research is required to determine risk factors, the role of adjunctive therapy, as well as long-term prognoses for peripheral nerve sheath tumors in rabbits