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Abstract

Objective—To test the hypothesis that differences in anesthetic uptake and elimination in iguanas would counter the pharmacokinetic effects of blood:gas solubility and thus serve to minimize kinetic differences among inhaled agents.

Animals—6 green iguanas (Iguana iguana).

Procedures—Iguanas were anesthetized with isoflurane, sevoflurane, or desflurane in a Latin-square design. Intervals from initial administration of an anesthetic agent to specific induction events and from cessation of administration of an anesthetic agent to specific recovery events were recorded. End-expired gas concentrations were measured during anesthetic washout.

Results—Significant differences were not detected for any induction or recovery events for any inhalation agent in iguanas. Washout curves best fit a 2-compartment model, but slopes for both compartments did not differ significantly among the 3 anesthetics.

Conclusions and Clinical Relevance—Differences in blood:gas solubility for isoflurane, sevoflurane, and desflurane did not significantly influence differences in pharmacokinetics for the inhalation agents in iguanas.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To optimize the use of CT-guided modeling for the calculation of body surface area (BSA) in domestic rabbits (Oryctolagus cuniculus).

Animals—12 domestic rabbits.

Procedures—Adult rabbits (body weight, 1 to > 4 kg) that were client-owned animals undergoing CT for disease diagnosis or deceased laboratory animals donated from other research projects were scanned with a CT scanner. Images were transferred to a radiation therapy planning software program. Image slices were captured as contiguous slices at 100 kVp and 100 mA and processed to 0.1-cm-thick sections. The length of each contoured slice was summed to calculate a final BSA measurement. Nonlinear regression analysis was then used to derive an equation for the calculation of BSA in rabbits.

Results—The constant calculated by use of this method was 9.9 (range, 9.59 to 10). The R 2 for the goodness of fit was 0.9332. The equation that best described BSA as a function of body weight for domestic rabbits with this method was as follows: BSA = (9.9 × [body weight {in grams}]2/3)/10,000.

Conclusions and Clinical Relevance—The BSA calculated via the CT-guided method yielded results similar to those obtained with equations for other similarly sized mammals and verified the use of such equations for rabbits. Additionally, this technique can be used for species that lack equations for the accurate calculation of BSA.

Full access
in American Journal of Veterinary Research

Abstract

CASE DESCRIPTION

An 8-year-old sexually intact female eclectus parrot (Eclectus roratus) with a 4-day history of hyporexia and lethargy and a 1-day history of tenesmus was examined.

CLINICAL FINDINGS

Severe leukocytosis characterized by severe heterophilia and moderate monocytosis was present. Marked dilation of the proventriculus and ventriculus and ascites were identified by means of radiography, coelomic ultrasonography, and contrast-enhanced CT, with no clinically relevant motility noted on ultrasonography. Results of coelomic fluid analysis were consistent with pyogranulomatous effusion. Endoscopy of the upper gastrointestinal tract following proventricular and ventricular lavage showed a thick caseous plaque occupying 30% of the caudal proventricular mucosa. Abundant yeast organisms were evident during cytologic examination of a proventricular and ventricular wash sample, and fecal culture yielded Candida glabrata.

TREATMENT AND OUTCOME

The bird was treated with SC fluids, assisted feedings, nystatin, fluconazole, amoxicillin–clavulanic acid, enrofloxacin, gastroprotectants, maropitant, and analgesics and slowly improved during hospitalization. A marked decrease in proventricular dilation was evident on serial radiographs obtained over a 12-month period. One year after diagnosis, the bird was presented with a 1-week history of hyporexia and lethargy, and fecal culture grew C glabrata. Antifungal treatment was resumed for 3 months. The bird had no clinical signs of infection 16 months after this recurrence, and subsequent fecal cultures were negative for fungal growth.

CLINICAL RELEVANCE

Findings illustrate the importance of upper gastrointestinal endoscopy in diagnosing proventricular and ventricular dilation in birds and emphasize the need for long-term antifungal treatment and monitoring in birds with fungal infections.

Full access
in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE To describe the prevalence, histologic characteristics, concomitant abnormalities, and outcomes for various types of mammary gland tumors in companion rats (Rattus norvegicus).

DESIGN Retrospective case series.

ANIMALS 100 client-owned rats.

PROCEDURES Medical records of companion rats that had an SC mass and were examined at a veterinary teaching hospital between 1990 and 2015 were reviewed. Information regarding the signalment, age at mass detection, reproductive sterilization status, histologic diagnosis of the SC mass, location of the initial and all subsequent SC masses, treatments administered, and clinical outcomes was extracted from each record and summarized.

RESULTS 105 SC masses were initially detected in 100 rats. The most prevalent SC mass identified was mammary gland fibroadenoma (56/105 [53%]), followed by mammary gland carcinoma (13/105 [12%]). Overall, 26 of 105 (25%) masses were malignant. Sexually intact males were more likely to have nonmammary SC tumors than sexually intact females. In rats receiving no adjunctive treatment after excision of a mammary gland fibroadenoma (n = 16), a second fibroadenoma was detected 1 to 8 months after initial excision, at a median of 4.5 months after surgery. A concomitant pituitary gland tumor was identified in most rats with mammary gland fibroadenoma (21/28 [75%]) and other types of mammary gland tumors (10/17 [59%]). Fourteen of 35 (40%) rats with mammary gland fibroadenoma had concomitant reproductive tract abnormalities.

CONCLUSION AND CLINICAL RELEVANCE Results suggested that, like other species, companion rats with SC masses should undergo a thorough diagnostic workup that includes histologic examination of the excised mass.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To calculate the prevalence of urolithiasis in client-owned chelonians examined at a veterinary teaching hospital and to describe the clinical signs, diagnosis, and treatment of urolithiasis in chelonians.

Design—Retrospective case series.

Animals—40 client-owned turtles and tortoises with urolithiasis.

Procedures—The medical record database of a veterinary teaching hospital was searched from 1987 through 2012 for records of client-owned chelonians with urolithiasis. The prevalence of urolithiasis was calculated for client-owned chelonians examined at the hospital. Signalment and physical examination, hematologic, biochemical, urinalysis, diagnostic imaging, treatment, and necropsy results were described.

Results—The mean prevalence of urolithiasis in client-owned chelonians for the study period was 5.1 cases/100 client-owned chelonians examined. Thirty-one of the 40 chelonians were desert tortoises. Only 5 of 40 chelonians had physical examination abnormalities associated with the urogenital tract. Surgery was performed on 17 chelonians; 5 developed postoperative complications, and 4 of those died. Necropsy was performed on 18 chelonians, and urolithiasis contributed to the decision to euthanize or was the cause of death for 9. Uroliths from 13 chelonians were analyzed, and all were composed of 100% urate.

Conclusions and Clinical Relevance—Results indicated chelonians with urolithiasis have various clinical signs and physical examination findings that may or may not be associated with the urinary tract. Hematologic, biochemical, and urinalysis findings were nonspecific for diagnosis of urolithiasis. Many chelonians died or were euthanized as a consequence of urolithiasis, which suggested the disease should be identified early and appropriately treated.

Full access
in Journal of the American Veterinary Medical Association

Abstract

CASE DESCRIPTION

A 4-year-old spayed female mixed-breed rabbit was evaluated because of a 3-year history of sneezing and nasal discharge that were refractory to medical management.

CLINICAL FINDINGS

Signs of chronic left-sided rhinitis and sinusitis were observed on physical examination and confirmed by CT evaluation. Lysis of the rostral aspect of the left maxillary bone and destruction of nasal turbinates were evident on CT images.

TREATMENT AND OUTCOME

Pararhinotomy of the left maxillary sinus through the facies cribrosa was performed. Purulent material was removed from the maxillary sinus recesses, a middle meatal antrostomy was completed to allow permanent drainage into the left middle nasal meatus, and the tissues were closed routinely. Microbial culture of a sample from the maxillary sinus recesses revealed Bordetella bronchiseptica, undetermined fastidious nonenteric bacteria, and Streptococcus viridans. Medical management was continued, and nasal discharge resolved but sneezing persisted. Increased sneezing and bilateral nasal discharge developed 1.5 years later; CT examination revealed right-sided rhinitis, and culture of a nasal swab sample revealed Bordetella spp, Staphylococcus spp, and Micrococcus spp. Right-sided pararhinotomy and middle meatal antrostomy were performed, and medical management continued. A subsequent recurrence was managed without additional surgery; 4 years after the initial surgery, the rabbit was still receiving medical treatment, with mild intermittent nasal discharge and sneezing reported.

CLINICAL RELEVANCE

This report describes a surgical approach for treatment of chronic rhinitis in companion rabbits with maxillary sinus involvement that included creation of a permanent drainage pathway from the maxillary sinus to the middle nasal meatus.

Full access
in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE To determine the clinical features, treatment, and outcomes of treatment for oral and cutaneous squamous cell carcinoma (SCC) in avian species.

DESIGN Retrospective case series with nested cohort study.

ANIMALS 87 client-owned birds of various species with histologically confirmed SCC of the skin or oral cavity.

PROCEDURES Clinicians entered case information through an online survey tool. Data were collected regarding patient signalment, concurrent conditions, treatments, adverse effects, and clinical outcomes. Relationships were examined between complete excision and partial or complete response. Survival analysis was performed to compare outcomes among groupings of therapeutic approaches.

RESULTS Only 7 of 64 (11%) birds for which full outcome data were available had complete remission of SCC; 53 (83%) had progressive disease, were euthanized, or died of the disease. The unadjusted OR for partial or complete response following complete tumor excision (vs other treatment approaches) was 6.9 (95% confidence interval [CI], 1.8 to 25.8). Risk of death was 62% lower (hazard ratio, 0.38; 95% CI, 0.19 to 0.77) for birds that underwent complete excision versus conservative treatment. Median survival time from initial evaluation for birds receiving complete excision was 628 days (95% CI, 210 to 1,008 days), compared with 171 days (95% CI, 89 to 286 days) for birds receiving monitoring with or without conservative treatment. Birds receiving any other additional treatment had a median survival time of 357 days (95% CI, 143 to 562 days).

CONCLUSIONS AND CLINICAL RELEVANCE For birds with SCC, complete excision was the only treatment approach significantly associated with complete or partial response and increased survival time.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine dispersion uniformity and stability of meloxicam and carprofen in extemporaneous preparations stored for 28 days.

Design—Prospective study.

Sample Population—Meloxicam and carprofen (commercial formulations) were compounded (day 0) with deionized water (DW), 1% methylcellulose gel (MCG), MCG and simple syrup (SS; 1:1 mixture), or a suspending and flavoring vehicle combination (SFVC; 1:1 mixture) to nominal drug concentrations of 0.25, 0.5, or 1.0 mg/mL and 1.25, 2.5, or 5.0 mg/mL, respectively.

Procedures—Preparations were stored at approximately 4°C (39.2°F) or 22°C (71.6°F). For each preparation, drug concentrations were determined and drug stability was evaluated at intervals during storage; on days 0 and 28, pH values were measured and bacterial cultures were initiated.

Results—In meloxicam-DW, meloxicam-MCG (0.25 mg/mL), and meloxicam-MCG (0.5 mg/mL) preparations, drug distribution was uniform (coefficient of variation < 10%); > 90% of the original drug concentration was maintained for 28 days. Despite uniform drug distribution of the carprofen-SFVC preparations, most retained ≥ 90% of the original drug concentration for only 21 days. Use of the MCG-SS combination resulted in foamy preparations of unacceptable variability. After 28 days, pH decreased slightly in meloxicam-DW and meloxicam-MCG preparations (0.17 ± 0.04 and 0.21 ± 0.04, respectively). Carprofen-SFVC (2.5 mg/mL) and carprofen-MCG-SS (5.0 mg/mL) preparations stored at 22°C for 28 days yielded bacterial growth.

Conclusions and Clinical Relevance—DW, MCG, and the SFVC can be used successfully for extemporaneous preparation of meloxicam and carprofen for administration to small exotic animals. Refrigeration is recommended for preparations of meloxicam-DW and carprofen-SFVC.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Case Description—An 8-month-old spayed female domestic ferret (Mustela putorius furo) was referred for examination to determine the cause of lethargy and severe anemia.

Clinical Findings—Initial examination revealed that the ferret was lethargic but with appropriate mentation. The only other abnormal findings were severe pallor of the mucous membranes, nasal planum, and skin and a PCV of 8%. Pure red cell aplasia (PRCA) was diagnosed on the basis of cytologic evaluation of a bone marrow biopsy specimen.

Treatment and Outcome—Medical treatment included blood transfusions, IM administration of iron dextran, oral administration of antimicrobials and gastrointestinal tract protectants, and SC administration of erythropoietin. Once PRCA was diagnosed, the ferret was orally administered prednisone, cyclosporine, and azathioprine. Nine months after onset of treatment, the PRCA was in remission and the ferret was doing well. Immunosuppressive treatment was discontinued at 14 months after onset of treatment, and 36 months after initial examination, the ferret appeared to be healthy.

Clinical Relevance—It is important that PRCA be considered as a differential diagnosis for a ferret with severe anemia. Prolonged immunosuppressive treatment was successful in the ferret described here. (J Am Vet Med Assoc 2010;237:695-700)

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine the distribution and clinical outcome of ocular lesions in snakes.

Design—Retrospective case series.

Animals—67 snakes with ocular lesions.

Procedures—Signalment, lesion duration, diagnosis, treatment, and clinical outcome were recorded for all snakes with ocular lesions that were examined at a veterinary teaching hospital from 1985 to 2010.

Results—71 ocular lesions were detected in 67 of 508 (13%) snakes examined. Affected snakes were of the families Boidae, Pythonidae, Colubridae, and Viperidae. The distribution of ocular lesions did not vary by taxonomic family, age, or sex; however, snakes from the genus Epicrates with ocular lesions were overrepresented in the population. The most commonly diagnosed ocular lesions were retained spectacle (n = 41), pseudobuphthalmos or subspectacular abscess (13), trauma (8), and cataracts (4). Pseudobuphthalmos or subspectacular abscess developed more frequently in Colubridae than in non-Colubridae snakes. Of the 16 snakes with retained spectacles for which data were available, the lesion recurred once in 4 snakes and multiple times in 5 snakes.

Conclusions and Clinical Relevance—Results indicated that retained spectacle was the most common ocular lesion diagnosed in snakes. Compared with other snakes with ocular lesions, snakes of the genus Epicrates had a higher than expected frequency of ocular lesions in general and snakes of the family Colubridae had a higher than expected frequency of pseudobuphthalmos or subspectacular abscess.

Full access
in Journal of the American Veterinary Medical Association