Effects of intravenous administration of lidocaine and buprenorphine on gastrointestinal tract motility and signs of pain in New Zealand White rabbits after ovariohysterectomy.

OBJECTIVE To compare analgesic and gastrointestinal effects of lidocaine and buprenorphine administered to rabbits undergoing ovariohysterectomy. ANIMALS Fourteen 12-month-old female New Zealand White rabbits. PROCEDURES Rabbits were assigned to 2 treatment groups (7 rabbits/group). One group received buprenorphine (0.06 mg/kg, IV, q 8 h for 2 days), and the other received lidocaine (continuous rate infusion [CRI] at 100 µg/kg/min for 2 days). Variables, including food and water consumption, fecal output, glucose and cortisol concentrations, and behaviors while in exercise pens, were recorded. RESULTS Rabbits receiving a lidocaine CRI had significantly higher gastrointestinal motility, food intake, and fecal output and significantly lower glucose concentrations, compared with results for rabbits receiving buprenorphine. Rabbits receiving lidocaine also had a higher number of normal behaviors (eg, sprawling, traveling, and frolicking) after surgery, compared with behaviors such as crouching and sitting that were seen more commonly in rabbits receiving buprenorphine. Both groups had significant weight loss after surgery. Pain scores did not differ significantly between treatment groups. Significant decreases in heart rate and respiratory rate were observed on the day of surgery, compared with values before and after surgery. Rabbits in the lidocaine group had significantly overall lower heart rates than did rabbits in the buprenorphine group. CONCLUSIONS AND CLINICAL RELEVANCE A CRI of lidocaine to rabbits provided better postoperative outcomes with respect to fecal output, food intake, and glucose concentrations. Thus, lidocaine appeared to be a suitable alternative to buprenorphine for alleviating postoperative pain with minimal risk of anorexia and gastrointestinal ileus.

BAYLISASCARIS PROCYONIS LARVA MIGRANS IN TWO CAPTIVE NORTH AMERICAN BEAVERS (CASTOR CANADENSIS).

Baylisascaris procyonis larva migrans was diagnosed in two North American beavers ( Castor canadensis ) belonging to a zoological park in Clarke County, Georgia. Both beavers presented with neurological signs. One beaver died naturally and despite attempted treatment, the other beaver was euthanatized because of severe clinical signs and poor prognosis. Histologic evaluation of the beavers revealed evidence of parasitic migration characterized by several lesions, including eosinophilic granulomas in various organs, as well as necrotizing eosinophilic and lymphoplasmacytic to granulomatous polioencephalitis, leukoencephalitis and cervical leukomyelitis. This represents the first confirmed case of B. procyonis larva migrans in beaver and the first non-raccoon ( Procyon lotor ) host in the southeastern United States. This report highlights the need for clinicians and diagnosticians to consider baylisascariasis in animals with compatible clinical signs. Preventative measures should be considered for captive animals, because early diagnosis of B. procyonis is challenging, and treatment is often unrewarding.

Endocrine tumours in the guinea pig.

Functional endocrine tumours have long been thought to be rare in guinea pigs, although conditions such as hyperthyroidism and hyperadrenocorticism have been documented with increasing frequency so the prevalence of hormonal disorders may have been underestimated. Both the clinical signs and diagnosis of hyperthyroidism in guinea pigs appear to be very similar to those described in feline hyperthyroidism, and methimazole has been proven to be a practical therapy option. Hyperadrenocorticism has been confirmed in several guinea pigs with an adrenocorticotropic hormone stimulation test using saliva as a non-invasive sample matrix; trilostane has been successfully used to treat a guinea pig with hyperadrenocorticism. Insulinomas have only rarely been documented in guinea pigs and one animal was effectively treated with diazoxide.

Use of a Nitinol Wire Stent for Management of Severe Tracheal Stenosis in an Eclectus Parrot (Eclectus roratus).

A 25-year-old, female eclectus parrot (Eclectus roratus) presented for dyspnea 3 weeks after anesthesia and surgery for egg yolk coelomitis. Radiography, computed tomography, and tracheoscopy revealed multiple tracheal strictures spanning a length of 2.6 cm in the mid to distal trachea. Histopathologic examination revealed mild fibrosis, inflammation, and hyperplasia consistent with acquired tracheal strictures. Tracheal resection was not considered possible because of the length of the affected trachea. The strictures were resected endoscopically, and repeated balloon dilation under fluoroscopic guidance over the course of 10 months resulted in immediate but unsustained improvement. Computed tomography was used to measure the stenotic area. A 4 × 36-mm, custom-made, nitinol wire stent was inserted into the trachea under fluoroscopic guidance. After stent placement, intermittent episodes of mild to moderate dyspnea continued, and these responded to nebulization with a combination of saline, acetylcysteine, and dexamethasone. Multiple attempts to wean the patient off nebulization therapy and to switch to a corticosteroid-free combination were unsuccessful. The parrot eventually developed complications, was euthanatized, and necropsy was performed. Histologically, the tracheal mucosa had widespread erosion to ulceration, with accumulation of intraluminal exudate and bacteria, severe degeneration of skeletal muscle and tracheal rings, prominent fibrosis, and mild to moderate, submucosal inflammation. Clinicopathologic findings in this case suggested tracheomalacia, which has not been previously described in birds. Custom-made tracheal stents can be used for severe tracheal stenosis in birds when tracheal resection and anastomosis is not possible. Complications of tracheal stent placement in birds may include tracheitis and tracheomalacia. To our knowledge, this is the first report of tracheal stent placement in an avian species.

Diagnostic quality of percutaneous fine-needle aspirates and laparoscopic biopsy specimens of the liver in rabbits (Oryctolagus cuniculus).

OBJECTIVE: To evaluate diagnostic quality of liver percutaneous ultrasound-guided fine-needle aspirates and laparoscopic biopsy specimens of rabbits (Oryctolagus cuniculus). DESIGN: Prospective descriptive study. ANIMALS: 7 healthy adult rabbits. PROCEDURES: 3 to 5 liver fine-needle aspirates were obtained with a 22-gauge needle under ultrasound guidance in anesthetized rabbits. Liver biopsy specimens were also obtained with 1.7-mm (n = 2) or 3.0-mm (1) biopsy forceps by direct laparoscopic observation. Fine-needle aspirates were cytologically evaluated on a scale from 0 (suboptimal specimen) to 3 (optimal specimen) for cellularity, cell distribution, cell preservation, cell morphology, and blood contamination. Biopsy specimens were histologically evaluated on a scale from 0 (optimal specimen) to 5 (suboptimal specimen) for artifactual changes; numbers of portal triads and central veins were quantified. RESULTS: Aspirates were moderately to highly cellular (mean, 2.54) with good cell distribution (mean, 2.56), good cell preservation (mean, 2.20), and moderate blood contamination (mean, 1.04). The 1.7-mm biopsy specimens had a mean score of 1.3 for artifactual changes and contained a mean of 0.6 portal triads and 1.6 central veins/biopsy specimen. The 3.0-mm liver biopsy specimens had a mean score of 2.7 for artifactual changes, with a mean of 4.0 portal triads and 4.14 central veins/biopsy specimen. All but one 3.0-mm liver biopsy specimen had ≥ 1 portal triad suitable for histologic evaluation, and all had ≥ 1 central vein; in contrast, only half of the 1.7-mm liver biopsy specimens had a discernible portal triad or central vein. CONCLUSIONS AND CLINICAL RELEVANCE: For histologic evaluation, advantages of obtaining 3.0-mm liver biopsy specimens, compared with 1.7-mm liver biopsy specimens or fine-needle aspirates, should be considered in rabbits with suspected liver disease.

Antemortem Diagnosis and Successful Treatment of Pulmonary Candidiasis in a Sun Conure (Aratinga solstitialis).

An adult male sun conure (Aratinga solstitialis) was evaluated because of lethargy, ruffled feathers, and decreased appetite. Physical examination revealed hypothermia, dehydration, dyspnea, and crop distention. Results of a complete blood cell count revealed a marked inflammatory leukogram, and cytologic examination of a crop swab sample identified gram-negative bacilli and occasional yeast organisms. Radiographs demonstrated an opaque, ill-defined, soft tissue structure in the caudal coelom just cranial to the renogonadal silhouette, loss of serosal detail, and splenomegaly. Endoscopic examination revealed a pale, granuloma-like structure within the caudal aspect of the left lung, splenomegaly, and an enlarged proventriculus. Intraoperative cytologic examination of a biopsy sample of the lesion demonstrated yeast organisms, and a subsequent culture of the biopsy sample revealed Candida albicans . The bird was treated intraoperatively with intralesional amphotericin B. Postoperative treatment consisted of meloxicam, trimethoprim sulfa, amphotericin B by nebulization, and systemic itraconazole and fluconazole. The bird made a complete recovery, was discontinued from all medications, and has remained asymptomatic for 6 months. Although rare, pulmonary candidiasis should be on the list of differential diagnoses for any respiratory infection in birds. Endoscopic biopsy, cytology, and fungal culture were valuable in making the diagnosis.

Diagnosis and treatment of proventricular nematodiasis in an umbrella cockatoo (Cacatua alba).

CASE DESCRIPTION: A 16-year-old female umbrella cockatoo (Cacatua alba) was referred to the University of Georgia College of Veterinary Medicine for evaluation of a 3-year seasonal history of lethargy and weight fluctuation. CLINICAL FINDINGS: Abnormalities detected via clinicopathologic analyses included mild leukocytosis, heterophilia, and lymphopenia consistent with a stress leukogram. Previous fecal examinations failed to diagnose enteric parasite infestation. Results of a fecal flotation test with Sheather sugar solution revealed spirurid eggs (Spiruroidea). Coelomic radiography revealed a widened cardiohepatic waist with increased soft tissue opacity at the level of the hepatic silhouette. The caudal thoracic and abdominal air sacs bilaterally appeared compressed against the coleomic wall. The proventriculus was increased in diameter, with a proventriculus-to-keel ratio of 1.0. Coelomic ultrasonography and positive-contrast upper gastrointestinal radiography revealed severe thickening and irregularity of the proventricular wall. The animal was anesthetized for an endoscopic examination of the upper gastrointestinal tract. Intralesional nematodes were identified on histologic examination of biopsy specimens from the proventriculus. TREATMENT AND OUTCOME: Effective fenbendazole treatment (15 mg/kg [6.8 mg/lb], PO, alternating between 5 days of treatment and 5 days of no treatment, which continued for 4 periods) was confirmed by repeated endoscopy and fecal examinations. The bird remained free of clinical signs 27 months after diagnosis and treatment. CLINICAL RELEVANCE: Antemortem diagnosis of proventricular nematodiasis has not been reported in psittacines. Spirurid nematode eggs are shed intermittently, which may lead to false-negative results on a single routine fecal examination. In this patient, radiography, endoscopy, and histologic evaluation facilitated antemortem diagnosis. This is the first report of successful treatment of this condition in psittacines.

Productive thyroid follicular carcinoma in a wild barred owl (Strix varia).

An adult male barred owl (Strix varia) was found unable to fly on a pasture during the day. On presentation, several lacerations were noted on the left wing. The animal was anesthetized for radiographic examination, which revealed mild swelling and irregularity of the soft tissues of the left wing. Over the plane of the syrinx and great vessels, ill-defined soft tissue opacity was present. The anesthetic recovery was unsuccessful, and the patient died. On gross necropsy, a 1 cm in diameter, round, soft, red-tan nodule, with scattered light tan to white foci was noticed between the right subclavian artery and the syrinx. The histopathology of this structure was characteristic of a thyroid follicular carcinoma. Neoplastic cells were immunoreactive to thyroglobulin and pancytokeratin proteins. A blood sample, taken antemortem, was analyzed for total and free thyroxine. Due to the lack of reference intervals for the current species, 4 blood samples from other barred owls were taken, 2 of which were clinically normal and 2 with an unhealthy status. The thyroid values were higher than the controls (total thyroxine by radioimmunoassay [µg/dl] 1.1 vs. <0.2, <0.2, 0.6, <0.2; free thyroxine by equilibrium dialysis [ng/dl] >10 vs. <0.3, <0.3, 2.1, <0.3). Although the other 4 birds are not intended to serve as a reference interval because of the low number and unhealthy status, findings are indicative of a productive thyroid follicular carcinoma.

Extralabel use of cabergoline in the treatment of a pituitary adenoma in a rat.

CASE DESCRIPTION: A 0.65-kg (1.43-lb) 24-month-old sexually intact male albino pet rat was examined because of a 3-week history of hypodipsia, apparent blindness, and sudden change in behavior. CLINICAL FINDINGS: The rat was able to move around its cage but appeared unaware of its surroundings, was visually unresponsive, and seemed unusually aggressive. The rat's hind limbs appeared mildly paretic, and it had sporadic difficulty placing its hind limbs on a flat surface. Given the rat's age, history, and physical examination findings, the primary differential diagnosis was a pituitary tumor. Magnetic resonance imaging (MRI) of the rat's brain was performed and revealed a large pituitary mass, which was indicative of a tumor. TREATMENT AND OUTCOME: Cabergoline (0.6 mg/kg [0.27 mg/lb], PO, q 72 h) was administered. On follow-up MRI 2 months later, the pituitary mass had substantially decreased in size. For 6 months following the second MRI study, the rat continued to receive the same dosage of cabergoline and had no clinical signs of disease or unusual behavior. However, at 8.5 months after the start of the treatment, the rat was in poor condition and had clinical signs similar to those initially. A third MRI study was performed and revealed substantial regrowth of the mass. The rat was euthanized and a necropsy was performed; a histopathologic diagnosis of pituitary adenoma was made. CLINICAL RELEVANCE: Pituitary adenomas have long been recognized as a common finding in geriatric rats (> 18 months old). Affected rats may respond favorably to oral administration of cabergoline.

The use of BoneWelding® technology in spinal surgery: an experimental study in sheep.

The innovative BoneWelding(®) technology, where ultrasound energy bonds bioresorbable implants to bone, was tested for its feasibility in spine surgery and its local thermal effects. The three tested concepts consisted of implementation of a resorbable plating system, two converging polymer pins and suture anchors to the cervical vertebral bodies. Bioresorbable polylactide implants (PLDLLA 70/30) were inserted ventrally into the third and fourth vertebral body of seven sheep, of which six were sacrificed at 2 months and one sheep immediately after temperature measurements during implant insertion. Polymer screws were used as controls. Qualitative, semi-quantitative histological, and quantitative histomorphometrical evaluation showed excellent anchorage of the implants, new mineralized bone at the implant-bone interface, no inflammatory cell reaction or thermal damage to the adjacent bone in response to the novel insertion technology. The application of two converging pins, parallel inserted polymer pins, or fusion of the implant to the polymer plates did not affect the overall excellent tissue tolerance of the technology. Temperature increase during insertion was noticed but never exceeded 47°C for less than 1 s. The BoneWelding(®) technology was proven to be safe and easy to apply.

Disseminated, histologically confirmed Cryptococcus spp infection in a domestic ferret.

CASE DESCRIPTION: A 4-year-old castrated male domestic ferret from central Massachusetts was evaluated for weight loss over a 1.5-month period and for 2 days of retching, diarrhea, and signs of lethargy. It had been housed indoors, with 2 other ferrets, 2 cats, and humans that lacked signs or symptoms of disease. CLINICAL FINDINGS: Physical examination revealed a thin body condition, tachypnea, an increase in respiratory effort, and retching. Splenomegaly was detected during abdominal palpation. Clinicopathologic analysis revealed lymphopenia, lactic acidosis, hypoglycemia, hypocalcemia, hypoalbuminemia, and hyperglobulinemia. A pulmonary bronchointerstitial pattern was evident on radiographs, and abdominal ultrasonography revealed a suspected pancreatic mass and mesenteric lymphadenopathy. TREATMENT AND OUTCOME: After 2 weeks of medical treatment and once clinical signs resolved, an exploratory laparotomy was performed and a lymph node biopsy specimen was collected. Histologic evaluation of the specimen revealed Cryptococcus-like organisms. Antifungal treatment was initiated with itraconazole (PO) and amphotericin B (IV). The ferret died after 2 days of treatment. A full necropsy was performed, revealing multicentric cryptococcosis affecting the lungs, brain, spleen, and multiple lymph nodes. Paraffin-embedded, formalin-fixed lung tissue was submitted for DNA extraction, and the organism was identified as Cryptococcus neoformans var grubii. CLINICAL RELEVANCE: To the authors' knowledge, this is the first report of disseminated cryptococcosis in a North American ferret. This case is unique in that the ferret lived indoors, in a geographic region in which reports of cryptococcosis are rare. The genotyping technique used to identify the Cryptococcus strain can aid in better understanding the epidemiology of cryptococcosis.