Encephalitozoon cuniculi in pet rabbits

The results of a serological test for Encephalitozoon cuniculi in 125 pet rabbits are reviewed, together with follow-up studies of clinical cases. Blood samples were taken from 38 asymptomatic rabbits and 87 rabbits showing neurological, renal or ocular signs suggestive of encephalitozoonosis. In the asymptomatic group, six of 26 (23 per cent) apparently healthy rabbits, sampled as part of a health screen, were seropositive; of the remaining 12 asymptomatic rabbits, sampled because they lived with seropositive companions, eight (66 per cent) were seropositive. Fifty-eight of the rabbits with clinical disease showed neurological signs, including head tilt, seizures, ataxia and swaying; three of them also showed renal signs and two showed ocular signs, and these five rabbits were all seropositive. Head tilt was the most common neurological sign in 21 of 23 (91 per cent) of the seropositive cases. All nine rabbits with ocular lesions were seropositive. In follow-up studies of clinical cases, the rabbits showed variable responses to treatment with albendazole, fenbendazole, antibiotics or corticosteroids, and some cases recovered without treatment.     

Hepatic coccidiosis in two pet rabbits

Hepatic coccidiosis is a frequent disease in rabbits. However, limited information is available pertaining to hematology, biochemistry, and ultrasonography of the liver in naturally infected rabbits. Two young emaciated rabbits presented with diarrhea. Microscopic fecal examination identified ellipsoidal oocysts. Eosinophilia, thrombocytopenia, elevated alkaline phosphatase, alanine aminotransferase, globulin, and gamma-glutamyl transferase, and decreased serum albumin, amylase, blood urea nitrogen, and creatinine were detected. Ultrasonography showed mild ascites, an enlarged liver with heterogeneous parenchyma, dilated hepatic blood vessels, and dilated bile ducts. Despite treatment with trimethoprim-sulfamethoxazole and toltrazuril both rabbits died. Necropsy revealed ascites and an enlarged liver with multiple yellowish nodules. Histologically, distended bile ducts almost completely replaced the hepatic parenchyma, and numerous coccidial gametocytes and oocytes were observed. Microscopic fecal examination, hematology, biochemistry, and ultrasonography of the liver can contribute to diagnose of hepatic coccidiosis.     

Cryptosporidium infection in juvenile pet rabbits

Cryptosporidium infection was confirmed by fecal examination for the first time in pet rabbits in a wholesale store located in Kanagawa Prefecture, Japan. Fecal samples were obtained postmortem from juvenile rabbits (n=66), which had died after developing diarrhea. Feces from healthy rabbits (n=30) were also collected and examined as controls. Two types of Cryptosporidium oocysts distinctive in size and shape were found (Type A and B). Types A and B oocysts were detected from 16.7% and 13.6% of the diarrheic, and 3.3% and 0% of the normal feces, respectively. Since Cryptosporidium oocysts were detected at a higher rate in the diarrheic rabbits than in the healthy rabbits, special caution should be taken when handling a pet rabbit presenting with diarrhea.     

Sedation and anesthesia of pet rabbits

Pet rabbits frequently become stressed when handled and may require sedation or chemical immobilization for procedures such as blood collection, IV catheter placement, radiography, deep ear cleaning, and dentistry. Common surgical procedures requiring general anesthesia include spay, castration, gastrotomy, cystotomy, and orthopedic procedures. Rabbits may be difficult to safely sedate or anesthetize. Individual rabbits may have varying sensitivity to the depressant effects of anesthetics. The apparent sensitivity of the rabbit's respiratory center to anesthetic drugs and the narrow range between anesthetic and toxic doses in this species add to the unpredictable character of rabbit anesthesia. Furthermore, mortality following anesthesia and surgery in sick rabbits is common. Strategically, safe anesthesia of rabbits must include the planning of procedures so that anesthetic time is minimized. Clinicians must be on guard for individual variation in response to drugs. Minimizing the use of cardiovascular depressant agents, use of agents with a high therapeutic index, and careful titration of doses to effect, along with thorough cardiorespiratory monitoring, will permit attainment of appropriate anesthetic depth with the widest margin of safety. This article presents several injectable and inhalant anesthetic protocols that may assist in effective management of many types of rabbit patient.     

Rabies virus infection in a pet guinea pig and seven pet rabbits

Raccoon-variant rabies was confirmed in 7 pet rabbits and 1 pet guinea pig in New York State, and postexposure treatment was required in several adults and children. To prevent rabies virus infection, domestic rabbits and pet rodents should be protected from contact with wild animals, including double-cage housing when housed outside. Pet rabbits or rodents with any possible contact with a wild animal, particularly if the rabbit or rodent had wounds of unknown origin, should be quarantined for 6 months for observation, to prevent escape, and to avoid contact with humans, who will require treatment if the rabbit or rodent develops rabies. Bites and scratches to humans from rodents and lagomorphs should be evaluated for potential rabies exposure on an individual basis, with consideration of whether the animal was caged outside or permitted outdoors unsupervised.     

Congestive heart failure in two pet rabbits

This case report describes congestive heart failure with pleural effusion in two middle-aged, pet house rabbits. Both had a history of acute onset dyspnoea, weakness and weight loss. Bi-atrial enlargement was seen on echocardiography in both rabbits. One rabbit had atrial fibrillation and ventricular premature complexes identified on electrocardiography. There was a radiographically evident pleural effusion in both rabbits and thoracocentesis was undertaken in one rabbit. These findings were confirmed on post-mortem examination. The aetiology for the underlying heart disease was not found, but the potential types of cardiomyopathies are discussed.     

Coxofemoral luxation in pet rabbits: nine cases

Of the pet rabbits presented at one private practice between August 2011 and August 2016 (n=1369), 5·6% presented with a traumatic orthopaedic injury. Of these, 7·8% (n=6) presented with traumatic coxofemoral luxation, the most frequently observed type of luxation. Three cases of non‐traumatic coxofemoral luxation in pet rabbits are also discussed. Eight rabbits presented with craniodorsal luxation and one with caudoventral luxation. Five rabbits were initially treated using closed reduction and an Ehmer sling under sedation. Two rabbits responded satisfactorily to closed reduction; their bandages remained in place for 10 and 14 days, and movement was cage‐limited for 1 month after bandage placement. The bandage did not prevent re‐luxation in three cases. Therefore, two rabbits received iliofemoral nylon sutures, and three rabbits received a femoral neck and head ostectomy. One rabbit was treated directly using open reduction and an iliofemoral nylon suture due to fractures in the same limb. One rabbit was presented in shock, coxofemoral luxation was noticed as an incidental finding and euthanasia was elected by the owner. In conclusion, of the three rabbits treated via femoral neck and head ostectomy one rabbit had an unsatisfactory outcome and two rabbits have non‐assessable outcomes. The three rabbits treated with iliofemoral sutures showed satisfactory long‐term outcomes and the two rabbits treated with closed reduction and an Ehmer sling showed satisfactory medium and long‐term outcomes.     

The species-specific feeding of rabbits in pet husbandry

To meet nutrient demands as well as the species specific requirements of an animal it is absolutely necessary to know its nutrition physiology (KAMPHUES et al. 1999). Characteristics of the nutrition physiology of rabbits include the anatomy of the intestinal tract (i.e. the teeth, the size of gut as well as the small intestine and colon), the special ingesting behaviour (selection, intensity of gnawing and chewing) and digestive processes within the intestinal tract (digestion by own as well as by microbial enzymes, processes of separation (producing soft faeces) and the excretion of digested or undigested nutrients (excretion via faeces or kidneys, quality of faeces). In feeding pet rabbits it has to be recommended, that these species do not need concentrates, but ingredients with higher crude fiber contents due to their origin and their intestinal tract. Therefore these herbivorous species should be fed with hay, straw or vegetables and not with concentrates exclusively. If these components are not offered (an usual feeding practice in rabbits kept as companion animals), other products rich in crude fibre have to be fed. The offer of a pressed diet in cube form with long fibrous ingredients would be a possibility to upgrade a ration poor in crude fibre. To meet the gnawing requirement of the rabbits this cubes should be pressed intensively. Furthermore it is advisable to exchange ingredients of the mixed feed with a high energy content (i.e. sunflower seeds, nuts) for ingredients of lower energy density (i.e. oat hulls, pelleted ground hay). Finally calcium oversupply has to be avoided because higher calcium intake may result in urolithiasis (calcium stones/concrements).     

Clinical symptoms and diagnosis of encephalitozoonosis in pet rabbits

Infections with Encephalitozoon cuniculi in rabbits are observed at increasing frequency and are known as opportunistic infections in immunocompromised humans. 191 pet rabbits with suspected encephalitozoonosis, presented at the Animal Hospital of the Veterinary University of Vienna (Austria), were included in this study. Rabbits were serologically examined for antibodies against E. cuniculi (144 positive out of 184 rabbits with suspected encephalitozoonosis compared to 14 positive out of 40 clinically healthy rabbits tested as part of a standard health check) and Toxoplasma gondii (8 positive out of 157). Of the 144 seropositive rabbits with clinical signs, 75% showed neurological symptoms, 14.6% demonstrated phacoclastic uveitis and 3.5% suffered from renal failure. 6.9% of the animals had combined symptoms. Vestibular disease dominated within the rabbits that showed neurological symptoms. Polymerase chain reaction (PCR) could not detect parasite DNA in urine or cerebrospinal fluid (CSF), but did so in 4 out of 5 samples of liquefied lens material in cases with phacoclastic uveitis due to lens capsule rupture. Additionally further diagnostic procedures, such as inspection of the external ear canal (N=69), radiography of the tympanic bullae (N=65) were performed to rule out differential diagnosis. 54.2% of the patients exhibiting neurological symptoms recovered within a few days, while 87.5% of the rabbits suffering from renal failure died or had to be euthanized.     

Appropriate handling of pet rabbits: a literature review

Many rabbits show fear behaviours when lifted off the ground. Estimates from owner surveys suggest that around 60% of pet rabbits struggle when lifted and fear‐related aggression is common. This article integrates information from both laboratory and pet rabbit studies to formulate a list of recommendations for appropriate handling of rabbits. Reduction of the frequency of the stressor can be achieved by educating owners on alternative management practices to reduce the need to carry their rabbits. However, in some situations, it is unavoidable that a rabbit is lifted. Amelioration of the stress in these instances can be achieved by a 2 pronged strategy. First, the population of rabbits can be made more resilient to infrequent stressors by selectively breeding for confident rabbits and by better socialisation of unweaned kits, and, where possible, training of individual animals to permit handling. Secondly, any unavoidable lifting can be made less stressful by educating veterinary staff in appropriate methods of holding rabbits during both consultations and inpatient care. Better understanding of appropriate interactions with rabbits will improve welfare.     

Clinical value of blood glucose measurement in pet rabbits

Blood glucose was measured with a portable glucose meter in 907 rabbits, including 238 clinically healthy ones. Blood glucose concentrations ranged from 1.2 to 30.1 mmol/l. Diabetes mellitus was not encountered. No significant effect of sex or sedation was found. Hypoglycaemia was seen in 16 rabbits including one with an insulinoma. There was a significant relationship between blood glucose, food intake, signs of stress and severity of clinical disease. Rabbits showing signs of stress had higher blood glucose than rabbits with no signs and rabbits that were totally anorexic had higher blood glucose values than those that were eating normally or those with reduced food intake. Severe hyperglycaemia (>20 mmol/l) was associated with conditions with a poor prognosis. Rabbits with confirmed intestinal obstruction had a mean blood glucose of 24.7 mmol/l (n=18). This was significantly higher than the rabbits with confirmed gut stasis, which had a mean value of 8.5 mmol/l (n=51). The conclusion of the study was that blood glucose is a measurable parameter that can be used to assess the severity of a rabbit's condition and help to differentiate between gut stasis and intestinal obstruction in rabbits that are anorexic.     

Cutaneous neoplasms in pet rabbits: a retrospective study

Over a 16-year period, 190 tumors and tumorlike lesions from 179 pet rabbits were submitted for histopathologic examination. A total of 23 different tumor types and 1 tumorlike lesion were diagnosed. The most common diagnoses were trichoblastoma, collagenous hamartoma, and Shope fibroma. Viral-induced tumors were Shope fibroma (19) and Shope papilloma (2). Common nonviral epithelial tumors included trichoblastoma (59), squamous cell carcinoma (5), squamous papilloma (4), trichoepithelioma (3), and apocrine carcinoma (3). Common mesenchymal tumors were lipoma (10), liposarcoma (3), myxosarcoma (9), malignant peripheral nerve sheath tumor (8), fibrosarcoma (7), and leiomyosarcoma (4). Malignant melanoma was diagnosed in 8 rabbits. Collagenous hamartomas were diagnosed in 26 rabbits. Mesenchymal proliferations occurred significantly more often in male rabbits than in females. Collagenous hamartomas and myxosarcomas occurred exclusively in male animals, and 3 rabbits had multiple collagenous hamartomas. Immunohistochemistry was applied in cases in which a definite diagnosis could not be reached on hematoxylin and eosin slides. Follow-up information was received in 19 cases. Carcinomas recurred (2 of 3) or metastasized (1 of 3), whereas sarcomas frequently recurred (7 of 12). One malignant melanoma (1 of 3) and one poorly differentiated round cell neoplasm recurred (1 of 1). This is the first comprehensive retrospective analysis on skin neoplasia in pet rabbits.