Lateral ear canal resection and bulla osteotomy with marsupialization to treat otitis media in rabbits: forty-eight procedures.

OBJECTIVE: Describe lateral ear canal resection and bulla osteotomy with marsupialization (LECARBOM) in rabbits with otitis media (OM), and report outcomes, complications, bacteria cultured from middle ears, and their antimicrobial susceptibility testing (AST) results. STUDY DESIGN: Retrospective clinical case series; single referral hospital. ANIMALS: Forty-two rabbits with naturally occurring OM. METHODS: Medical records (2011-2021) of rabbits with CT-confirmed OM undergoing surgery were reviewed for outcomes, complications, bacteria cultured from middle ears, and AST. RESULTS: Surgery was performed on 48 ears, and outcomes determined 21 days postoperatively. All rabbits survived the procedure. Otitis externa resolved in all lop-eared rabbits. Of 29 ears with OM-associated head tilt, eight (28%) resolved, nine (31%) improved, seven (24%) remained unchanged and five (17%) worsened. Outcome was not associated with head tilt duration nor OM severity. Postoperative complications occurred in 12 (25%) cases, seven of which had wound margin dehiscence that healed by 21 days. The most frequent bacteria isolated were Pasteurella multocida (16%), Bordetella bronchiseptica (14%) and Staphylococcus aureus (14%). Bacteria were sensitive to azithromycin, marbofloxacin or enrofloxacin and resistant to penicillin. CONCLUSION: LECARBOM is a well-tolerated surgical procedure to treat OM. It also improved or stabilized 83% of cases with head tilt and resolved all cases with otitis externa. CLINICAL SIGNIFICANCE: LECARBOM with administration of an AST-sensitive antibiotic, or azithromycin when no AST is performed, should be effective in rabbits with OM. Postsurgically, it resolves or alleviates most secondary conditions such as otitis externa, head tilt and facial nerve paralysis.

CLOUDED LEOPARD (NEOFELIS NEBULOSA) MORBIDITY AND MORTALITY IN CAPTIVE-BRED POPULATIONS: A COMPREHENSIVE RETROSPECTIVE STUDY OF MEDICAL DATA FROM 271 INDIVIDUALS IN EUROPEAN, ASIAN, AND AUSTRALIAN ZOOS.

The clouded leopard (Neofelis nebulosa) is classified as vulnerable on the International Union for the Conservation of Nature Red List of Threatened Species. However, diseases affecting this species across zoo populations are not well documented. The primary objective of this retrospective study was to identify common and significant causes of morbidity and mortality in captive-bred clouded leopards from European, Asian, and Australian institutions. Medical records from 44 zoological parks that held 271 clouded leopards from 1934 to 2017 were reviewed. Major causes of mortality in the dead leopards (n = 141) were respiratory disease (17%), maternal neglect and starvation (12%), generalized infectious disease (10%), digestive disease (10%), and trauma (10%). Six animals lived more than 20 yr and two were older than 22 yr. Diseases were recorded 344 times (average of two per leopard) in 166 living leopards. The body systems most frequently affected by disease in these 166 individuals were, in order of frequency, integumentary (prevalence = 21%), digestive (21%), respiratory (16%), musculoskeletal (12%), and urinary (10%) systems. Neoplasia (7%) was less frequent, followed by cardiovascular (5%), genital (3%), and viral (3%) disorders. Extensive, self-induced alopecia on the tail and dorsum was the most frequently reported dermatological disease, which is proposed to be called the "clouded leopard alopecia syndrome." The most common neoplasm was pheochromocytoma (1%), followed by squamous cell carcinoma of the paw pads, pleural mesothelioma and multicentric lymphomas (<1% each). Dilated cardiomyopathy (2%) was the most common cardiovascular disease. Bronchopneumonia (7%), enteritis (4%), and nephritis (4%) were the most frequently reported respiratory, digestive, and renal diseases, respectively. Diagnosed disease incidence was significantly higher in Europe. This paper reports the results of a comprehensive study of the causes of morbidity and mortality in European, Asian, and Australian clouded leopard zoo populations.

Keratomycosis in a pet rabbit (Oryctolagus cuniculus) treated with topical 1% terbinafine ointment.

This report describes the clinical presentation, diagnosis, and medical management of a 2-year-old spayed female dwarf rabbit (Oryctolagus cuniculus) suffering from an ulcerative keratitis and a stromal abscess with a rapid evolution. The diagnosis of fungal keratitis was based on fungal culture identifying the pathogen as Aspergillus fumigatus. Treatment by topical terbinafine was efficacious in resolving the keratomycosis within 8 weeks. To our knowledge, this is the first reported case of spontaneous keratomycosis in a rabbit and the first description of successful therapy by terbinafine.

Traumatic elbow luxation in a free-ranging hedgehog (Erinaceus europaeus): surgical management using circumferential suture prostheses.

A free-ranging adult female hedgehog (Erinaceus europaeus) was presented injured, presumably from vehicular trauma. Clinical and radiographic examination under general anesthesia revealed a lateral elbow luxation. Closed reduction was unsuccessful, so a surgical approach with circumferential suture prostheses was used to stabilize the elbow. Neither perioperative nor postoperative complications were recorded. The hedgehog regained good range of motion of the elbow and was fully able to run and to roll into a ball.

Coccygeal chordoma in a degu: case report and review of the literature.

An 8-y-old, intact female degu ( Octodon degus) was presented with a slow-growing mass on the tail tip. The mass was completely removed by partial caudectomy. Histologically, the last coccygeal vertebra was replaced by a lobulated neoplasm composed of large clear polygonal cells embedded in a myxoid alcian blue-positive matrix with highly vacuolated cytoplasm (physaliferous cells) and intracytoplasmic periodic acid-Schiff-positive granules. The neoplasm exhibited the morphologic features of a "classic" chordoma of humans, which is 1 of 3 distinct chordoma subtypes. Immunohistochemistry revealed dual expression of cytokeratin AE1/AE3 and vimentin, consistent with a diagnosis of chordoma. Chordomas are uncommon slow-growing neoplasms in humans and animals, arising from notochordal remnants. Depending on their subtype and location, they can have a high local recurrence rate and metastatic risk. Chordoma should be included in the differential diagnosis of a soft tissue mass on the tail of a degu, similar to the clinical situation in ferrets.

A canine adenovirus type 2 vaccine vector confers protection against foot-and-mouth disease in guinea pigs.

Vaccination is a key element in the control of foot-and-mouth disease (FMD). The majority of the antigenic sites that induce protective immune responses are localized on the FMD virus (FMDV) capsid that is formed by four virus-encoded structural proteins, VP1 to VP4. In the present study, recombinant canine adenovirus type 2 (CAV2)-based FMD vaccines, Cav-P1/3C R° and Cav-VP1 R°, respectively expressing the structural P1 precursor protein along with the non-structural 3C protein or expressing the structural VP1 protein of the FMDV strain O/FRA/1/2001, were evaluated as novel vaccines against FMD. A strong humoral immune response was elicited in guinea pigs (GP) following immunization with Cav-P1/3C R°, while administration of Cav-VP1 R° did not induce a satisfying antibody response in GP or mice. GP were then used as an experimental model for the determination of the protection afforded by the Cav-P1/3C R° vaccine against challenge with the FMDV strain O1 Manisa/Turkey/1969. The Cav-P1/3C R° vaccine protected GP from generalized FMD to a similar extent as a high potency double-oil emulsion O1 Manisa vaccine. The results of the present study show that CAV2-based vector vaccines can express immunogenic FMDV antigens and offer protection against generalized FMD in GP. This suggest that Cav-P1/3C R° FMDV vaccine may protect natural host species from FMD. In combination with an appropriate diagnostic test, the Cav-P1/3C R° FMDV vaccine may also serve as a marker vaccine to differentiate vaccinated from infected animals.

Assessment and Care of the Critically Ill Rabbit.

Rabbits have the ability to hide their signs and often present in a state of decompensatory shock. Handling can increase susceptibility to stress-induced cardiomyopathy and specific hemodynamic changes. Careful monitoring with a specific reference range is important to detect early decompensation, change the therapeutic plan in a timely manner, and assess prognostic indicators. Fluid requirements are higher in rabbits than in other small domestic mammals and can be corrected both enterally and parenterally. Critical care in rabbits can be extrapolated to many hindgut fermenters, but a specific reference range and dosage regimen need to be determined.

Surgical management of multiple metatarsal fractures in a chinchilla (Chinchilla lanigera).

CASE DESCRIPTION A 3-month-old sexually intact female chinchilla (Chinchilla lanigera) was examined for sudden onset of non-weight-bearing lameness of the right hind limb. CLINICAL FINDINGS On physical examination, the right pes was swollen. An open wound on the medial aspect of the metatarsal region exposed the second metatarsal bone, and the pes was displaced laterally. Radiographs of the right pes revealed oblique displaced fractures of the 4 metatarsal bones. TREATMENT AND OUTCOME Surgical treatment was elected, and enrofloxacin was administered prior to surgery. The protruding fragment of the second metatarsal bone was excised, and the third and fourth metatarsal bones were repaired with intramedullary pins and external skeletal fixation. The chinchilla was bearing weight on the affected limb 9 days after surgery with only mild lameness. The implants were removed 35 days after surgery when radiographs showed bony union of the third and fourth metatarsal bones and continued reduction of the fractures of the second and fifth metatarsal bones. Fifty-six days after surgery, the chinchilla was bearing full weight on the limb, and radiographs showed bony union of the third, fourth, and fifth metatarsal bones. CLINICAL RELEVANCE Findings suggested that intramedullary pinning combined with an epoxy resin external fixator may be an effective technique for metatarsal fracture repair in chinchillas. This method allowed physiologic positioning of the limb and functional hind limb use during fracture healing. Prospective studies of fracture healing in exotic small mammals are indicated.

Flexible Gastrointestinal Endoscopy in Ferrets (Mustela putorius furo).

Gastrointestinal disease is a common complaint in ferrets (Mustela putorius furo). Their relatively simple and short gastrointestinal tract makes them good candidates for flexible endoscopy. However, apart from a few references in biomedical research articles, there is little information on the use of flexible endoscopy in ferrets. This review describes patient preparation, equipment, and select gastrointestinal endoscopy techniques in ferrets, including esophagoscopy, gastroscopy, duodenoscopy, percutaneous endoscopic gastrostomy, jejunoileoscopy, colonoscopy, and biopsy.

Intramuscular administration of alfaxalone for sedation in rabbits.

Alfaxalone is a neuroactive steroid derivative of pregnanedione that was recently reintroduced to the market for use as an induction agent in small animal anaesthesia. The aim of this study was to determine an intramuscular alfaxalone dose for safe immobilisation. Ten healthy New Zealand white rabbits were used to evaluate a single intramuscular injection of alfaxalone. The design of the study was a three-way, complete block, cross-over trial to compare the effect of alfaxalone at three doses (4, 6 and 8 mg). The mean duration of the effect for the 4, 6 and 8 mg/kg doses was, respectively, 36.9 (95% CI (31.6 to 42.3)), 51.8 (46.4 to 57.2) and 58.4 (52.8 to 63.9) minutes. The loss of the righting reflex was achieved after 3.1 (2.5 to 3.8), 2.4 (1.7 to 3.1) and 2.3 (1.6 to 2.9) minutes, respectively. The mean duration of the effect for the 6 and 8 mg doses was significantly higher than for the 4 mg dose (with estimated differences of 14.8 95% CI (8.8 to 20.8) minutes and 21.4 (15.3 to 27.6) minutes, respectively). No significant dose effect was observed before the loss of the righting reflex (P=0.14). Ear pinching and limb withdrawal were elicited in all groups at every dose. Doses of 4 or 6 mg/kg could be recommended; higher doses do not provide clinical benefits and can be associated with anaesthetic complication.

Comparative Analysis of Methods to Induce Myocardial Infarction in a Closed-Chest Rabbit Model.

OBJECTIVE: To develop a rabbit model of closed-chest catheter-induced myocardial infarction. Background. Limitations of rodent and large animal models justify the search for clinically relevant alternatives. METHODS: Microcatheterization of the heart was performed in 47 anesthetized 3-4 kg New Zealand rabbits to test five techniques of myocardial ischemia: free coils (n = 4), interlocking coils (n = 4), thrombogenic gelatin sponge (n = 4), balloon occlusion (n = 4), and alcohol injection (n = 8). In order to limit ventricular fibrillation, an antiarrhythmic protocol was implemented, with beta-blockers/amiodarone before and xylocaine infusion during the procedure. Clinical, angiographic, and echographic data were gathered. End points included demonstration of vessel occlusion (TIMI flow grades 0 and 1 on the angiogram), impairment of left ventricular function at 2 weeks after procedure (by echocardiography), and pathologically confirmed myocardial infarction. RESULTS: The best arterial access was determined to be through the right carotid artery. The internal mammary guiding catheter 4-Fr was selected as the optimal device for selective intracoronary injection. Free coils deployed prematurely and tended to prolapse into the aorta. Interlocking coils did not deploy completely and failed to provide reliable results. Gelatin sponge was difficult to handle, adhered to the catheter, and could not be clearly visualized by fluoroscopy. Balloon occlusion yielded inconsistent results. Alcohol injection was the most efficient and reproducible method for inducing myocardial infarction (4 out of 6 animals), the extent of which could be fine-tuned by using a coaxial balloon catheter as a microcatheter (0.52 mm) to achieve a superselective injection of 0.2 mL of alcohol. This approach resulted in a 20% decrease in LVEF and infarcted myocardium was confirmed histologically. CONCLUSIONS: By following a stepwise approach, a minimally invasive, effective, and reproducible rabbit model of catheter-induced myocardial infarction has been developed which addresses the limitations of rodent experiments while avoiding the logistical and cost issues associated with large animal models.

Gastrointestinal Disease in Exotic Small Mammals.

Exotic small mammal medicine is a relatively new specialty area within veterinary medicine. Ferrets, rabbits, and rodents have long been used as animal models in human medical research investigations, resulting in a body of basic anatomic and physiologic information that can be used by veterinarians treating these species. Unfortunately, there is a paucity of veterinary articles that describe clinical presentation, diagnosis, and treatment options of gastrointestinal (GI) disease as it affects exotic small mammals. Although there is little reference material relating to exotic small mammal GI disease, patients are commonly presented to veterinary hospitals with digestive tract disorders. This article provides the latest information available for GI disease in ferrets (Helicobacter mustelae gastritis, inflammatory bowel disease [IBD], GI lymphoma, systemic coronavirus, coccidiosis, and liver disease), rabbits (GI motility disorders, liver lobe torsion, astrovirus, and coccidiosis), guinea pigs (gastric dilatation volvulus [GDV]), rats (Taenia taeniaeformis), and hamsters (Clostridium difficile). Both noninfectious diseases and emerging infectious diseases are reviewed as well as the most up-to-date diagnostics and treatment options.

Evaluation of heart murmurs in chinchillas (Chinchilla lanigera): 59 cases (1996-2009).

OBJECTIVE: To determine the prevalence of heart murmurs in chinchillas (Chinchilla lanigera) and determine whether heart murmurs were associated with cardiac disease. DESIGN: Retrospective multi-institutional case series. ANIMALS: 260 chinchillas. PROCEDURES: Medical records of all chinchilla patients evaluated at the Tufts University Foster Hospital for Small Animals between 2001 and 2009, the University of California-Davis William R. Pritchard Veterinary Medical Teaching Hospital between 1996 and 2009, and the University of Wisconsin Veterinary Medical Teaching Hospital between 1998 and 2009 were reviewed. RESULTS: Prevalence of heart murmurs was 23% (59/260). Of 15 chinchillas with heart murmurs that underwent echocardiography, 8 had echocardiographic abnormalities, including dynamic right ventricular outflow tract obstruction, mitral regurgitation, hypertrophy of the left ventricle, tricuspid regurgitation, and hypovolemia. Echocardiographic abnormalities were approximately 29 times as likely (OR, 28.7) to be present in chinchillas with a murmur of grade 3 or higher than in chinchillas without a murmur. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that heart murmurs are common in chinchillas and that chinchillas with heart murmurs often have echocardiographic abnormalities, with valvular disease being the most common. On the basis of these results, we believe that echocardiography should be recommended for chinchillas with heart murmurs, especially older chinchillas with murmurs of grade 3 or higher. Further prospective studies are needed to accurately evaluate the prevalence of cardiac disease in chinchillas with heart murmurs.

Zoonoses of ferrets, hedgehogs, and sugar gliders.

With urbanization, people live in close proximity to their pets. People often share their living quarters and furniture, and this proximity carries a new potential for pathogen transmission. In addition to the change in lifestyle with our pets, new exotic pets are being introduced to the pet industry regularly. Often, we are unfamiliar with specific clinical signs of diseases in these new exotic pets or the routes of transmission of pathogens for the particular species. This article reviews zoonoses that occur naturally in ferrets, hedgehogs, and sugar gliders, discussing the occurrence and clinical symptoms of these diseases in humans.