Four cases of iridociliary tumors in domestic rabbits (Oryctolagus Cuniculus).

Spontaneously occurring ocular neoplasia is rarely reported in rabbits. This case series presents four cases of rabbits diagnosed with iridociliary tumors, which have not been previously reported in this species. Major pathological findings include epithelial tumors affecting the anterior uvea with variable pigmentation and basement membrane formation. Follow-up information was only available for two cases, but neither showed evidence of metastasis, suggesting that the prognosis for these tumors in rabbits, as in other species, may be very good.

Bayesian Decision Analysis: An Underutilized Tool in Veterinary Medicine.

Bayesian inference and decision analysis can be used to identify the most probable differential diagnosis and use those probabilities to identify the best choice of diagnostic or treatment among several alternatives. In this retrospective case analysis, we surveyed three experts on the prior probability of several differential diagnoses, given the signalment and history of a ferret presenting for lethargy and anorexia, and the conditional probability of different clinical findings (physical, bloodwork, imaging, etc.), given a diagnosis. Using these data and utility estimates provided by other clinicians, we constructed a decision tree to retrospectively identify the optimal treatment choice between exploratory laparotomy and medical management. We identified medical management as the optimal choice, in contrast to the original clinical team which performed an exploratory laparotomy. We discuss the potential cognitive biases of the original clinical team. We also discuss the strengths, e.g., shared decision making, and limitations of a Bayesian decision analysis in the veterinary clinic. Bayesian decision analysis can be a useful tool for retrospective case analysis and prospective decision making, especially for deciding on invasive interventions or end-of-life care. The dissimilarity of expert-derived probability estimates makes Bayesian decision analysis somewhat challenging to apply, particularly in wide-ranging specialties like zoological medicine.

Respiratory Disorders in Ferrets.

Ferrets are susceptible to many disorders affecting the respiratory tract including both primary diseases and diseases of other body systems secondarily affecting the respiratory tract. Some primary respiratory diseases are shared with other mammal species including humans; potentially zoonotic diseases include important pathogens such as influenza and SARS-CoV-2. Other diseases include infections (bacterial, parasitic, and fungal) and neoplasia. A thorough workup is important to identify exact causes in order to formulate a treatment plan. Infectious diseases include bacterial, fungal, parasitic, and viral.

End-of-Life Decisions: Palliative Care, Hospice, and Euthanasia for Exotic Animals.

A great deal of attention has been directed toward developing better options for palliative care and hospice, and improving euthanasia techniques in all species. Euthanasia of exotic pets is technically more difficult because of anatomic differences and small patient size. Traditional intravenous euthanasia techniques in conscious patients are stressful and should generally be avoided in exotic pets; simple intramuscular administration of high dosages of anesthetics followed by delivery of euthanasia solutions is preferred. Options for mammals, birds, and reptiles are presented.

Disease Overview of the Urinary Tract in Exotic Companion Mammals and Tips on Clinical Management.

Diseases of the urinary tract are reviewed, covering infectious (bacterial, viral, parasitic), degenerative, congenital, metabolic, nutritional, neoplastic, obstructive, and toxic causes. Some clinical presentations and diagnostic procedures are described for ferrets, rabbits, guinea pigs, hamsters, mice, rats, chinchillas, hedgehogs, and sugar gliders, as well as therapies.

Malignant melanoma in a zebra finch (Taeniopygia guttata): cytologic, histologic, and ultrastructural characteristics.

An approximately 3-year-old adult male zebra finch (Taeniopygia guttata) was diagnosed with malignant melanoma. The large darkly pigmented tumor was located in the coelom, extended from the apex of the heart to the cloaca, and was adherent to the intestines and the ventriculus. Dark small masses (likely metastases) were observed in the lungs. Cytologically, the neoplasm consisted mainly of round to oval cells with brown or pale blue to blue-brown pigment. Lesser numbers of cells were stellate to dendritic with abundant amounts of brown pigment granules or were markedly pleomorphic with variable amounts of pigment. Histologically, the tumor consisted of dense sheets and aggregates of infiltrative melanocytes that were negative for S-100 and Melan A. A few cells were consistent with "signet-ring" melanocytes. Melanocytes examined by electron microscopy contained typical structures, mainly premelanosomes and melanosomes, of this cell type. However, melanocytes with marked pleomorphism also contained intracytoplasmic aggregates of filaments, consistent with previously reported ultrastructural findings in signet-ring or rhabdoid melanoma of nonavian species.

Mycobacteriosis in companion psittacine birds: a review.

Mycobacteriosis has long been recognized as a disease of companion psittacine birds. In this review, the signalment, clinical signs of disease, and diagnosis of mycobacteriosis in psittacine birds are presented. Although treatment of birds with mycobacteriosis is controversial, therapeutic protocols for use in psittacine birds have been developed based on protocols used in humans. Results of recent studies indicate that mycobacteriosis in psittacine birds is unlikely to represent a significant health risk for humans. However, the potential for zoonotic disease must be considered, especially if persons who are immunocompromised are in contact with an infected bird.

Reproductive Disorders of Marsupials.

Marsupial reproduction differs significantly in anatomy and physiology from that of placental mammals. The gastrointestinal and urogenital tracts empty into a cloaca. Reproductive parameters include gestation and pouch time, as the fetus develops outside of the uterus. Captive marsupials discussed include sugar gliders), short-tailed opossums, Virginia opossums, and Tammar and Bennett's wallabies. Common disease conditions include joey eviction, pouch infections, mastitis, metritis, prostatitis, penile necrosis, and neoplasia. Common surgeries include penile amputation, castration, and ovario-vaginal-hysterectomy or ovario-hysterectomy. Therapeutics used for these conditions are presented.

Common procedures in other avian species.

Although psittacine species represent the majority of avian patients seen in most exotic animal practices, nonpsittacine species such as passerines and galliformes may be presented as pets, as members of zoo collections, or as injured or ill wildlife. Many features of handling, restraint, sample collection, medicine, and surgery are similar in psittacine and nonpsittacine species. In many cases, the equipment required will be similar as well, with a few modifications.

Anatomy and Disorders of the Oral Cavity of Miscellaneous Exotic Companion Mammals.

Unusual mammalian species such as the hedgehog, sugar glider, and miniature pig are encountered with increasing frequency in exotic companion medicine. Disease of the oral cavity can occur in any species; although occasionally encountered in exotic mammalian species, it is rarely described in the literature. Anatomy and dentition vary significantly; diagnosis and treatment are often extrapolated from that known in other species. The best-documented disease of the oral cavity in this group of species is oral neoplasia in the hedgehog.

Diagnostic imaging of the respiratory system in exotic companion mammals.

The level of care for smaller companion mammals has increased significantly during the past few years. Today, exotic companion mammals are acknowledged as a specific area of zoologic medicine. Owner demands for a higher level of care is increasing dramatically. Because most of these patients are small (less than 2 kg), this represents a great challenge, in particular for the field of diagnostic imaging. This article reviews the 5 main diagnostic imaging modalities currently available for investigation of the respiratory system of exotic companion mammals: radiography, ultrasonography, endoscopy, computed tomography, and magnetic resonance.

Care of the geriatric rabbit.

The average life span reported in laboratory and lay literature for the domestic rabbit is 5 to 10 years. The author and other veterinarians are now regularly seeing rabbits living to 9 or 10 years, the oldest reported in the author's practice being 14 years. Rabbits are herbivorous prey species with continually growing (elodont) teeth. This feature allows the geriatric rabbit to possess teeth that are essentially "new", a distinct advantage over geriatric carnivores. Expanded longevity, while generally desirable, necessarily accompanies an increase in geriatric disorders. This article examines the spectrum of disease that can affect the geriatric rabbit as well as crucial factors concerning the clinical management of the animal up to the end of its life. An improved understanding of geriatric disorders in pet rabbits allows early recognition and the opportunity to improve quality of life.

Bacterial and parasitic diseases of rabbits.

Bacterial disease is common in pet rabbits; parasitic disease occurs as well but at a much lower frequency. Of these, bacterial diseases of the respiratory tract and dental structures are seen most commonly in practice. Successful treatment depends on positive diagnosis of the disease process and causative agent. This article focuses on the more common bacterial and parasitic diseases encountered in clinical practice.

Emergency and critical care procedures in sugar gliders (Petaurus breviceps), African hedgehogs (Atelerix albiventris), and prairie dogs (Cynomys spp).

Less common exotic pet mammals are gaining in popularity. The Australian Sugar Glider, African Hedgehog, and prairie dog are seen regularly in exotic animal practices. They are subject to the same types of medical emergencies as more traditional pets, with the unfortunate addition of all too common underlying nutritional and husbandry-related disorders. Emergency stabilization and critical care are important first steps before collection of diagnostic test samples and administration of definitive medical care.

Equipment for Exotic Mammal and Reptile Diagnostics and Surgery.

The practice of veterinary medicine is facilitated by appropriate equipment, and exotic pet medicine is no exception. Exotic practitioners use standard or modified veterinary and human equipment, and now even enjoy the benefit of specialized products manufactured specifically for exotic pet practice.