The Rat Thoracic Ultrasound protocol: scanning technique and normal findings.

Respiratory diseases (especially pneumonia) are very common disorders in pet rats. The suspected diagnosis is mostly based on the clinical signs, thoracic auscultation, and thoracic radiography. However, auscultation is insensitive in determining the severity of the disease, and radiographs are often unremarkable. Non-cardiac thoracic ultrasonography is increasingly used in veterinary medicine; however, it has not been described in detail in rats. Thoracic ultrasonic examination was conducted on 400 client-owned conscious pet rats. The rats were examined in the period from June 2023 to August 2023 in two veterinary clinics. Due to the small size of the animal, different anatomical considerations, and different evaluation protocols, as well as to meet the optimal outcome of detailed thoracic ultrasound, a standard methodological protocol was developed, and the name RATTUS (Rat Thoracic Ultrasound) was proposed. Typical signs of normal RATTUS were described (bat sign, lung sliding, A-lines, abdominal curtain sign, ski jump sign, lung pulse, seashore sign in M-mode, and bamboo sign). The new evaluation of lung inflation symmetry by substernal access was also described. The methodical approach presented and the normal findings description are proposed to be used for a standard/routine thoracic ultrasound examination in pet rats.

Radical debridement guided by advanced imaging and frequent monitoring is an effective approach for the treatment of odontogenic abscesses and jaw osteomyelitis in rabbits: a review of 200 cases (2018-2023).

OBJECTIVE: To report the prevalence and document the treatment and outcome of odontogenic abscesses and associated jaw osteomyelitis in pet rabbits. ANIMALS: 200 client-owned rabbits. METHODS: Pet rabbits surgically treated using extraoral teeth extraction with marsupialization for abscesses of dental origin and jaw osteomyelitis were included in the study (February 2018 to February 2023). A case must have had pre- and postoperative computed tomographic study and a follow-up period of at least 4 months. RESULTS: In total, 113 male and 87 female rabbits were treated surgically. The mean age at the time of the diagnosis at the authors' clinic was 3 years and 11 months. Male rabbits suffered from odontogenic abscesses significantly more often than females. The mean surgical time varied from 25 to 95 minutes, based on the severity of the pathology and location. The wound healed completely in an average of 39.7 days (range, 14 to 145 days; 95% CI, 36.9 to 42.5 days). Major complications detected in 18.5% (37/200) cases were associated with prolonged healing time mostly due to the formation of a bone sequestrum and gingival suture failure. The disease-free time following abscess resolution was on average 29 months (range, 4 to 60 months). The recurrence of the odontogenic infection was 8% (16/200 cases). CLINICAL RELEVANCE: The radical surgical technique with the extraction of all the infected teeth with the removal of all affected tissue and osteomyelitic bone and regular follow-up wound management is an effective method for the treatment of odontogenic abscesses with jaw osteomyelitis.

Changes in rabbit lymphocyte subpopulations and activation following long-term administration of meloxicam.

Meloxicam is a commonly used analgesic in rabbits. However, its possible impact on lymphocyte subpopulations remained unknown. The aim of the study was to investigate a possible effect of long-term administration of meloxicam on rabbit lymphocyte subpopulations. The study included 8 rabbits given meloxicam orally once daily (1 mg/kg BW) for 14 days and 8 rabbits as a control group. Peripheral blood samples were collected on day 0 (before the first dose of meloxicam), day 3, 7 and 14. Samples were evaluated with a haematology analyser and a flow cytometer. A significant decrease in T: B cell ratio was found in all samples taken during meloxicam administration compared to day 0, as well as in comparison with the control group (P < 0.01). A significant increase (P < 0.05) in proportion of CD5 +CD8 + lymphocytes occurred by day 3. Subsequently, although the values slightly decreased, they still remained elevated throughout all the experiment compared to the values from day 0 (P < 0.05). A slight decrease in T and B cell activation (CD5 +CD25 + and IgM+CD25 +) noticed by day 3, declined during the next days of administration and became more and more significant (finally, P = 0.0078). Since a high significant decrease (P < 0.01) in both T and B cell activation as well as a significant increase (P < 0.05) in CD5 +CD8 + T cells proportion were observed after meloxicam administration, a predicted effect of long-term administration of meloxicam on rabbit lymphocytes was confirmed.

Cardiology in Rodents, Rabbits, and Small Exotic Mammals-Diagnostic Workup.

The incidence of cardiac diseases in pet rabbits and rodents increased over the past decade as these species live longer and diagnostics methods are more precise to diagnose heart diseases even in small-sized animals. The article summarizes diagnostics of cardiac diseases in selected exotic companion mammals, particularly in rabbits, guinea pigs, chinchillas, and rats. The emphasis of the paper is given on clinical examination, thoracic radiography, electrocardiography, and echocardiography.

Electrolyte, Oestradiol and Progesterone Concentrations in Ovarian Cyst Fluid in Guinea Pigs (Cavia porcellus).

Despite their high prevalence, the aetiopathogenesis of ovarian cysts in guinea pigs (Cavia porcellus) is unknown. We examined tissue samples of cystic ovaries from 20 guinea pigs by histopathology and immunohistochemistry for CD10 antigen, and determined the concentrations of Na+, K+, Cl-, oestradiol and progesterone in the cyst fluid. Cystic rete ovarii were found in all 20 guinea pigs but no follicular cysts. Concentrations of Na+ (142.2 ± 5.04 mmol/l), K+ (5.6 ± 0.76 mmol/l) and Cl- (116.1 ± 5.25 mmol/l) corresponded to extracellular, rather than intracellular, fluid indicating that rete ovarii cysts in guinea pigs are transudative in nature. A positive correlation was found between Na+ and Cl- concentrations (r = 0.7713, P <0.0001). The mean concentrations of oestradiol (61.9 ± 17.44 pg/ml) and progesterone (2.7 ± 5.42 ng/ml) in the cyst fluid were higher than expected because the rete epithelium is not known to have steroidogenic activity. A negative correlation was found between oestradiol and progesterone concentrations in cyst fluid (r = -0.4296, P = 0.0178). Possible pathogenetic mechanisms of cystic rete ovarii in guinea pigs are discussed.

Use of Micro-CT Imaging to Assess Ventral Mandibular Cortical Thickness and Volume in an Experimental Rodent Model With Chronic High-Phosphorus Intake.

Adverse effects of high dietary phosphorus on bone health have been observed in both animal and human studies. The aim of the investigation was to examine chronic effects of high phosphorus diet on the apical mandibular cortical thickness and volume in a hystricomorph rodent (Octodon degus) using microcomputed tomography. Male degus were randomly divided into two groups fed by different mineral contents from the age of 12 weeks till the age of 17 months. The micro-CT scanning and wall thickness analysis were applied on the region of the mandible exactly under the apices of the 4th premolar tooth, first molar tooth, and second molar tooth in two animals from each group. General overview and mapping of the ventral mandibular bone thickness revealed pronounced bony mandibular protrusions in all the animals fed a high-phosphorus diet with obvious bone thinning apically to the 4th premolar and first and second molar tooth apices. Mandibular bone volume and thickness located apically to the premolar and molars were statistically significantly smaller/thinner in the group fed by a high phosphorus diet. The thinnest bone measured 0.004 mm, where the mandibular 4th premolar tooth almost perforated the mandibular cortex. Similar studies of metabolic bone disease and its influence on alveolar bone were also published in rats and mice. The influence of different environmental, infectious, or metabolic factors on the growing tooth, alveolar bone formation, and bone pathologies must be done experimentally on growing animals. In contrast, degus have continuously growing dentition, and the effect of any of the above listed factors can be studied in this animal model at any age and for longer time periods.

Case Report: Spontaneous Appendicitis With Suspected Involvement of Klebsiella variicola in Two Pet Rabbits.

Although laboratory rabbits are commonly used as models of appendicitis in man, spontaneous appendicitis was only described ante-mortem in one pet rabbit with an acute abdomen. The aim of this article is to describe two spontaneous cases of appendicitis in pet rabbits, to describe therapeutic appendectomy, and to discuss the microbial flora of the inflamed appendix. A 5-month-old intact female and a 16-month-old, neutered male were presented to the veterinary clinic with restlessness, anorexia, and reduced faecal output. The main clinical findings were restlessness, severe discomfort on abdominal palpation, a mid-abdominal palpable tubulous mass and an elevated rectal temperature. Blood analyses showed lymphocytosis, monocytosis, and hyperglycaemia. Radiography was inconclusive. Abdominal ultrasound revealed a presence of a tubular structure with wall thicknesses of 4.2 and 3.7 mm in the two rabbits, respectively. The tubular structure had a rounded, closed end, and a multilayered wall, suggestive of appendicitis. Due to metabolic acidosis and poor prognosis, the first rabbit was euthanized. In the 16-month-old rabbit, appendectomy was performed. Recovery was uneventful, and 4 h after surgery, the rabbit started to become normally active. Postoperative care consisted of fluid therapy, multimodal analgesia, supportive care and prokinetics. Follow-up examinations at 10 days, 1 month, and at 11 months after the surgery did not show any abnormal clinical or laboratory findings. Histopathological examination of appendices from both rabbits showed gangrenous appendicitis. Aerobic cultivation showed the presence of pure culture of Klebsiella variicola sensitive to enrofloxacin, marbofloxacin, tetracycline, cefuroxime, trimethoprim sulphonamide, neomycin, and gentamicin. Restlessness associated with anorexia, abdominal pain, palpable abdominal mass, hyperglycaemia, lymphocytosis, and elevated rectal temperature may be indicative of inflammation within the gastrointestinal tract. Abdominal ultrasound is recommended in rabbits with showing these clinical signs because radiography can be inconclusive. Appendicitis is a life-threatening condition, which should be included into the list of differential diagnoses; for the rabbit, an acute abdomen and gastrointestinal stasis syndrome and must be treated immediately. K. variicola may be associated with appendicitis in rabbits as a causative agent or in association with appendix intraluminal dysmicrobia.

Urolithiasis in a captive Siberian chipmunk (Eutamias sibiricus).

This clinical case describes struvite urolithiasis in a pet chipmunk. Physical examination revealed the presence of two ovoid palpable masses in the caudal part of the abdomen, which were later confirmed by radiography as urinary bladder stone. The animal underwent ventral midline laparotomy and uroliths were successfully removed. Uroliths analysis revealed the presence of struvite and bacteriology showed the presence of Proteus mirabilis. Little is known about aetiology and incidence of urolithiasis in chipmunks. Client education about husbandry, dietary needs, and animal behaviour is necessary, especially when dealing with less commonly kept exotic companion mammals. This is the first report of struvite urolithiasis in a pet chipmunk.

Penicillin Treatment Failure in Rabbit Syphilis Due to the Persistence of Treponemes (Treponema paraluisleporidarum Ecovar Cuniculus) in the Focus of Infection.

Rabbit venereal spirochetosis, a disease caused by Treponema paraluisleporidarum ecovar Cuniculus (TPeC), affects both wild and pet rabbits, and is transmitted sexually and via direct contact among animals. Treatment of syphilis in pet rabbits requires administration of antibiotics, including penicillin G, chloramphenicol, or fluoroquinolones. The aim of this work was to elucidate the cause of penicillin treatment failure in rabbit syphilis in a pet rabbit treated in Brno, Czech Republic, and to assess the phylogenetic relatedness of the agent to previously characterized pathogenic treponemes. Following amputation of the infected digits, the second round of penicillin treatment using the same dosage and application route resulted in the disappearance of clinical symptoms within a period of two weeks. The bacterium was successfully isolated from the claws, propagated in three experimental rabbits, and the resulting TPeC strain was designated as Cz-2020. Analysis of four genetic loci revealed that the Cz-2020 strain was similar but also clearly distinct from the only TPeC strain, which had been characterized in detail to date, i.e., the Cuniculi A strain, which was isolated in North America. The strain Cz-2020 represents the first available viable TPeC strain of European origin. DNA sequences encoding five penicillin-binding proteins of the strain Cz-2020 were compared to those of Cuniculi A, which is known to be sensitive to penicillin. The sequences differed in six nucleotides resulting in single amino acid changes in Penicillin-binding protein 1, 2, and 3. Since the second round of treatment was successful, we conclude that the penicillin treatment failure in the first round resulted from the presence of infection foci in claws where treponemes persisted.

Respiratory Diseases in Guinea Pigs, Chinchillas and Degus.

The diagnosis and treatment of respiratory disease in pet guinea pigs, chinchillas, and degus still face profoundly serious challenges owing to their relatively small size, conspicuous clinical signs, difficulty for sampling, and insufficient scientific evidence to correlate signs and particular pathologies. This article is intended to summarize the available information on the relevant anatomy, physiology, and respiratory pathology in these species.

Respiratory Disorders in Rabbits.

Respiratory disorders are very common in rabbits. Rabbits are obligate nasal breathers, so "simple" rhinitis can cause severe respiratory distress and patient collapse. Causes of dyspnea could be of primary origin or secondary, whereby diseases primarily affecting other organs can result in respiratory embarrassment even if the respiratory system is healthy (eg, anemia, cardiac disease). Diagnosis is based on radiography, ultrasonography, endoscopy, computed tomography, and/or pathogen isolation. Once the diagnosis has been completed, treatment options should be discussed with the owner. The article describes the anatomy of the respiratory tract, diagnostics, and therapy for selected respiratory disorders in rabbits.

Mast cells and Kurloff cells - Their detection throughout the oestrous cycle in normal guinea pig ovaries and in guinea pigs with cystic rete ovarii.

Mast cells (MCs) and Kurloff cells (KCs) were detected in guinea pig ovaries in the follicular and luteal phases of the oestrous cycle. The samples of ovaries were fixed in Mota's basic lead acetate. Toluidine blue was used for detection of MCs and periodic acid-Schiff for detection of KCs. The percentage of KCs in a differential leukocyte count was determined in blood smears stained according to the Pappenheim method. Non-pregnant females with normal ovaries and with cystic rete ovarii were included in the study and the numbers of MCs and KCs were compared in these two groups and in follicular and luteal phases of the oestrous cycle. MCs' distribution in ovaries was different in the guinea pig in comparison to previously studied species: MCs were found exclusively in the superficial layers of cortical stroma and no significant difference was found between the number of MCs in the follicular and luteal phases, neither in normal ovaries, nor in ovaries with cystic rete ovarii. Significantly lower numbers of MCs were found in ovaries with cystic rete ovarii (P < 0.01) in contrast to normal ovaries. A significantly higher percentage of KCs in the peripheral blood was found in the follicular phase (P < 0.05), whereas no significant difference was found in relation to the presence of cystic rete ovarii. Interestingly, no KCs were found in the samples of ovaries (either in the follicular or luteal phase, and with or without cysts). Thus, the expected role of KCs in ovarian physiology or in the aetiology of the cystic rete ovarii can be excluded.

A case of a complete atrioventricular canal defect in a ferret.

BACKGROUND: Atrioventricular canal defect is a rare congenital disorder of the heart and describes the presence of an atrial septal defect, a variable presentation of ventricular septal alterations including ventricular septal defect malformations in the mitral and tricuspid valves. The defect has been described in human beings, dogs, cats, pigs, and horses. CASE PRESENTATION: This paper describes the case of a complete atrioventricular canal defect in a four-year-old intact male pet ferret (Mustela putorius furo), which was presented due to posterior weakness, ataxia, and decreased appetite. A loud systolic murmur, dyspnea, and hind limb paraparesis were detected during the clinical examination. Thoracic radiographs showed generalized cardiomegaly and lung edema. ECG showed sinus rhythm with prolonged P waves and QRS complexes. Echocardiography showed a large atrial septal defect, atrioventricular dysplasia, and a ventricular septal defect. Palliative treatment with oxygen, furosemide, spironolactone, enalapril, diltiazem, and supportive care was chosen as the therapy of choice. The ferret recovered gradually during hospitalization. A follow-up examination at three and six months showed stabilization of cardiac function. CONCLUSIONS: To the authors knowledge, this is the first time an atrioventricular canal defect has been described in a pet ferret.

Bilayer mucoadhesive buccal films with prolonged release of ciclopirox olamine for the treatment of oral candidiasis: In vitro development, ex vivo permeation testing, pharmacokinetic and efficacy study in rabbits.

The incidence of fungal infections has increased in recent decades not only in patients with predisposing and risk factors, but it has also spread up due to the widespread use of broad-spectrum antibiotics, immunosuppressants and corticosteroids. A limited number of drugs are currently used to treat oral candidiasis (OC). There is an emerging need to look for new antifungals, to rework or to explore the already known molecules. Ciclopirox olamine (CPX), a broad-spectrum antifungal agent, is currently used for topical dermatologic treatment. In this study, bilayer mucoadhesive buccal films (MBFs) containing poly(ethylene oxide) (PEO) and Eudragit® NM 30D (EU) with the prolonged release of ciclopirox olamine, were developed for the treatment of oral candidiasis. During ex vivo testing it was found that CPX does not pass through the porcine buccal tissue but it accumulates in it, which may be beneficial for the treatment of candidiasis in the oral cavity. In a pharmacokinetic study, the drug release from mucoadhesive films was prolonged with the maximum plasma concentration at 3.4 (1.4; 5.5) h. All rabbits with stomatitis showed progressive healing after the treatment with CPX bilayer mucoadhesive buccal films without organ pathologies.

Immunohistochemical Detection of Encephalitozoon cuniculi in Ocular Structures of Immunocompetent Rabbits.

Encephalitozoonosis is a common infectious disease widely spread among rabbits. Its causative agent, Encephalitozoon cuniculi, is considered as a zoonotic and emerging pathogen capable of infecting both immunocompetent and immunocompromised hosts, including humans. In rabbits, clinical signs include neurological, kidney and ocular disease. The aim of this study was to detect E. cuniculi in ocular structures in immunocompetent rabbits after experimental oral infection using immunohistochemistry. In infected animals, E. cuniculi spores were present in periocular connective tissue, sclera, cornea, choroidea, iris, retina and lens, as a round to ovoid organism reacting with a specific anti-E. cuniculi monoclonal antibody as early as 2 weeks after infection. There were no signs of inflammatory lesions in any of the ocular tissues examined at 2, 4, 6 and 8 weeks after infection. In the present study, E. cuniculi was also detected in the lenses of adult rabbits, which indicates that ways of lens infection other than intrauterine and haematogenic are possible.

Diagnostic imaging modalities and surgical anatomy of the temporomandibular joint in rabbits.

The temporomandibular joint (TMJ) is a condylar synovial joint that, together with the masticatory muscles, controls mandibular movement during mastication. The rabbit is often used as a model species for studying the mechanisms of TMJ diseases, and in regenerative research. However, there are significant differences between rabbit and human TMJs that should be taken into account before using this model for experimental research. Here, we use several analytical approaches (radiography, computed tomography and magnetic resonance imaging) to enable a detailed description and analysis of the rabbit TMJ morphology. Moreover, possible surgical approaches have been introduced with a focus on available access into the rabbit TMJ cavity, which relate our findings to clinical usage.

Evidence-Based Advances in Rodent Medicine.

The number of exotic companion pet rodents seen in veterinary practices is growing very rapidly. According to the American Veterinary Medical Association's surveys, more than 2,093,000 pet rodents were kept in US households in 2007 and in 2012 it was more than 2,349,000 animals. This article summarizes the most important evidence-based knowledge in exotic pet rodents (diagnostics of the hyperadrenocorticism in guinea pigs, pituitary tumors in rats, urolithiasis in guinea pigs, use of itopride as prokinetics, use of deslorelin acetate in rodents, cause of dental disease, and prevention of mammary gland tumors in rats).

Reproductive Medicine in Ferrets.

In the United States, desexing is performed routinely in ferrets at the age of 6 weeks, therefore reproductive tract diseases are not so common. However, in Europe most ferrets are desexed when they are several months old, or they are kept as intact animals. For this reason, diseases of the reproductive organs and a prolonged estrus are far more frequent in Europe than in the United States. This article summarizes and reviews the anatomy, reproductive physiology, management of reproduction (including surgical and hormonal contraception) and reproductive tract diseases in male and female ferrets.