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Abstract

Case Description—A 6-year-old female African pygmy hedgehog was evaluated because of a mass of unknown duration on the lateral aspect of the right shoulder region.

Clinical Findings—A fine-needle aspirate of the mass was collected for cytologic examination; findings were consistent with a spindle cell tumor. A CBC, plasma biochemical analyses, and whole-body radiography revealed no other abnormalities.

Treatment and Outcome—An initial surgery performed in an attempt to remove the mass with preservation of the limb failed in that tumor-free surgical margins were not obtained. Histologically, the mass was identified as a peripheral nerve sheath tumor (neurofibrosarcoma). A second surgery to amputate the forelimb was successful. After 1 year, there had been no further development of peripheral nerve sheath tumor at this or other sites.

Clinical Relevance—In African pygmy hedgehogs, potential differential diagnoses for a subcutaneous mass should include peripheral nerve sheath tumor. If necessary, forelimb amputation can be performed successfully in this species with procedures modified from those used in dogs. Information gathered during the treatment and recovery of the hedgehog of this report may assist practicing veterinarians in counseling owners of hedgehogs that are undergoing forelimb amputation with regard to the course of recovery that may be expected following this procedure.

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in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine the reliability of plasma electrophoresis (EPH) in psittacine birds.

Animals—93 psittacine birds.

Procedure—Jugular venipuncture was performed on 93 awake psittacine birds. The plasma was centrifuged, separated, aliquoted into duplicate samples, frozen, and sent to 2 commercial laboratories that routinely perform avian EPH. Samples from 51 birds were sent to laboratory A, and samples from 42 birds were sent to laboratory B. The reliability of EPH results within each laboratory was assessed, but not between laboratories. To determine the reliability (agreement between duplicate samples) of total protein, albumin, prealbumin, α1-, α2-, β-, and γ-globulin concentrations, the intraclass correlation coefficient ( ri ) was calculated.

Results—Both laboratories had excellent agreement between samples for measurement of total protein concentration and only good agreement for albumin concentration. Except for the prealbumin concentration measured at laboratory B, both laboratories had poor agreement for all other values of the EPH.

Conclusions and Clinical Relevance—These data indicate that plasma EPH for measuring prealbumin, α1-, α2-, β-, and γ-globulin concentrations may not be a reliable tool for assessing avian health. Small amounts of these proteins in birds plus human variation in reading the EPH curves may lead to variable results. Avian veterinarians should cautiously interpret results from plasma EPH assays for these protein fractions. (Am J Vet Res 2005;66:375–378)

Full access
in American Journal of Veterinary Research

Abstract

Objective—To determine agreement for total protein (TP) and albumin concentrations measured by a point-of-care biochemical analyzer in heparinized whole blood and plasma samples obtained from psittacines and compare results with those from a commercial laboratory.

Sample Population—Hematologic samples from 92 healthy birds.

Procedures—Duplicate samples of heparinized whole blood and plasma were obtained. A point-of-care biochemical analyzer was used to determine TP and albumin concentrations. To assess precision, intraclass correlation coefficient (r i) and Bland-Altman measures of agreement were used. These results were compared by use of Bland-Altman plots with those obtained from a commercial laboratory that used a biuret method for TP concentration and electrophoresis for albumin concentration.

Results—For the analyzer, there was excellent agreement (r i = 0.91) between heparinized whole blood and plasma samples for TP and albumin concentrations. Relative error was 0.9% for TP and 0.7% for albumin. Analyzer results correlated well with commercial laboratory results, with a downward bias of 0.6 for TP and 0.3 for albumin.

Conclusions and Clinical Relevance—The analyzer had excellent precision for analysis of heparinized whole blood or plasma samples for TP or albumin concentrations; analyzer values had good agreement with those from a commercial laboratory. The analyzer could be a valid method to measure plasma TP concentrations and provide point-of-care testing in apparently healthy parrots. Biochemical analyzer results for plasma albumin concentration were not validated by results from a commercial laboratory, so conclusions cannot be drawn regarding use of the analyzer in measurement of albumin concentrations in psittacines.

Full access
in American Journal of Veterinary Research

Abstract

Case Description—A 2-year-old female Solomon Island eclectus parrot (Eclectus roratus) was evaluated by a veterinarian because of a 4-day history of progressive lethargy, weakness, poor appetite, and inactivity. The bird was referred to a veterinary teaching hospital for further examination.

Clinical Findings—Clinicopathologic analyses revealed that the parrot had marked regenerative anemia, autoagglutination, and biliverdinuria. Small, rounded RBCs (thought to be spherocytes) were detected in blood smears. The abnormal findings met the diagnostic criteria for dogs with primary immune-mediated hemolytic anemia. However, analyses of blood samples for lead and zinc concentrations and plasma bile acids concentrations; the use of PCR assays for Chlamydophila psittaci, psittacine circovirus 1 (causative agent of beak and feather disease), and polyomavirus; and microbial culture and Gram staining of feces did not reveal a cause for the hemolytic anemia.

Treatment and Outcome—Although administration of immunosuppressive doses of cyclosporine was initiated, there was a rapid progression of disease, which lead to death of the parrot before this treatment could be continued long-term. Lack of an identifiable underlying disease (confirmed by complete histologic examinations at necropsy) supported the diagnosis of primary immune-mediated hemolytic anemia.

Clinical Relevance—Primary immune-mediated hemolytic anemia has not been widely reported in psittacine birds. A comprehensive evaluation and complete histologic examination of tissues to rule out underlying disease processes are required to definitively establish a diagnosis of primary immune-mediated hemolytic anemia in parrots. Primary immune-me-diated hemolytic anemia should be considered as a differential diagnosis for regenerative anemia in a parrot.

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in Journal of the American Veterinary Medical Association

Abstract

Case Description—A 2-year-old female green iguana was examined for anorexia and swelling and pain on palpation in the cranial cervical area.

Clinical Findings—Marked soft tissue swelling in the cranial cervical area with corresponding cystic swellings in the pharynx were noted. The iguana was considered to be 50% under the expected body weight, given diet and husbandry conditions. The WBC count was markedly elevated, characterized by heterophilia and lymphocytosis. Surgical exploration of the cranial cervical area and histologic and microbial testing identified lymphoma with secondary infection as the cause of the swelling.

Treatment and Outcome—The tumor was initially treated with a single 10-Gy fraction of radiation directed at the masses in the neck. A vascular access port was placed in the ventral abdominal vein, and a canine chemotherapy protocol was modified for use in the iguana. During the course of treatment, the protocol was modified twice. At 1,008 days from the initiation of treatment, the iguana appeared to be in remission.

Clinical Relevance—To our knowledge, this is the first reported use of radiation with doxorubicin, vincristine, cyclophosphamide, and prednisone to successfully manage lymphoma in a reptile. A vascular access port was used effectively for drug administration for an extended period. The doxorubicin, vincristine, cyclophosphamide, and prednisone protocol appeared to be safe and effective in this iguana for the management of lymphoma.

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in Journal of the American Veterinary Medical Association

Abstract

Objective—To ascertain whether Malassezia organisms can be detected via cytologic examination and fungal culture of samples from the skin surface of psittacine birds and determine whether the number of those organisms differs between unaffected psittacines and those that have chronic feather-destructive behavior or differs by body region.

Design—Prospective study.

Animals—50 unaffected psittacines and 53 psittacines that had feather-destructive behavior.

Procedure—Samples were collected by use of acetate tape strips from the skin of the head, neck, proventer, propatagium, inguinal region, and preen gland area of each bird; 0.5-cm2 sample areas were examined microscopically for yeast, and samples were also incubated on Sabouraud dextrose agar. Polymerase chain reaction assays specific for Malassezia spp, saprophytic fungi, and Candida albicans were performed on DNA prepared from cultured colonies; nested PCR evaluation for Malassezia pachydermatis was then performed.

Results—Microscopically, 63 of 618 (10%) tape-strip samples contained yeast. Thirty cultured colonies were assessed via PCR assays, and all yielded negative results for Malassezia spp; C albicans was identified in 2 colony samples. The numbers of yeast identified microscopically in psittacines with feather-destructive behavior and in unaffected birds did not differ significantly, and numbers did not differ by body region.

Conclusions and Clinical Relevance—Yeast were identified infrequently via cytologic examination of samples from the skin surface of unaffected psittacine birds or those that had chronic feather-destructive behavior. If yeast are identified on the skin of birds with feather-destructive behaviors, fungal culture of skin samples should be performed to identify the organism.

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in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE To evaluate the pharmacokinetics and bioavailability of 2 doses of orbifloxacin in rabbits.

ANIMALS 6 healthy purpose-bred adult female New Zealand White rabbits (Oryctolagus cuniculus).

PROCEDURES Each of 3 rabbits received orbifloxacin at either 10 or 20 mg/kg, PO. Then, after a 1-week washout period, they received the same dose IV. Blood samples were collected from each rabbit at 0, 0.25, 0.5, 1, 2, 4, 6, 12, and 24 hours after drug administration. Plasma orbifloxacin concentration was measured with liquid chromatography–tandem mass spectrometry. Pharmacokinetic parameters were determined by noncompartmental analysis for data obtained following PO administration and noncompartmental and compartmental analyses for data obtained following IV administration.

RESULTS Following oral administration, the mean ± SD peak plasma orbifloxacin concentration was 1.66 ± 0.51 μg/mL for rabbits administered the 10 mg/kg dose and 3.00 ± 0.97 μg/mL for rabbits administered the 20 mg/kg dose and was attained at 2 hours after drug administration. The mean ± SD half-life of orbifloxacin in plasma was 7.3 ± 1.1 hours for rabbits administered the 10 mg/kg dose and 8.6 ± 0.55 hours for rabbits administered the 20 mg/kg dose. Mean bioavailability was 52.5% for rabbits administered the 10 mg/kg dose and 46.5% for rabbits administered the 20 mg/kg dose.

CONCLUSIONS AND CLINICAL RELEVANCE Results provided pharmacokinetic properties for 2 doses (10 mg/kg and 20 mg/kg) of orbifloxacin oral suspension in rabbits. Further studies are necessary to determine the protein-binding activity of orbifloxacin in rabbits before dosages for the treatment of common pathogens in this species are recommended.

Full access
in American Journal of Veterinary Research
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine the long-term survival rate and factors that affect survival time of domestic ferrets treated surgically for hyperadrenocorticism.

Study Design—Retrospective case series.

Animals—130 ferrets with hyperadrenocorticism that were treated surgically.

Procedures—Medical records of ferrets surgically treated for hyperadrenocorticism were reviewed. Data recorded included signalment, duration of clinical signs prior to hospital admission, CBC values, serum biochemical analysis results, anesthetic time, surgical time, concurrent diseases, adrenal gland affected (right, left, or both [bilateral]), histopathologic diagnosis, surgical procedure, caudal vena caval involvement (yes or no), postoperative melena (yes or no), days in hospital after surgery, and whether clinical signs of hyperadrenocorticism developed after surgery.

Results—130 ferrets were entered in the study (11 of 130 ferrets were admitted and underwent surgery twice). The 1- and 2-year survival rates were 98% and 88%, respectively. A 50% survival rate was never reached. Combined partial adrenal gland resection with cryosurgery had a significantly negative effect on survival time. No other risk factors were identified. Survival time was not significantly affected by either histopathologic diagnosis or specific affected adrenal gland (right, left, or bilateral).

Conclusions and Clinical Relevance—Ferrets with adrenal gland masses that were treated surgically had a good prognosis. Survival time of ferrets with hyperadrenocorticism undergoing surgery was not affected by the histologic characteristic of the tumor, the adrenal glands affected (right, left, or bilateral), or complete versus partial adrenal gland resection. Debulking was a sufficient surgical technique to allow a favorable long-term outcome when complete excision was not possible.

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in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE To determine whether extent of collateral circulation would change during temporary occlusion of the caudal vena cava (CVC) in ferrets (Mustela putorius), a pressure change would occur caudal to the occlusion, and differences would exist between the sexes with respect to those changes.

ANIMALS 8 adult ferrets (4 castrated males and 4 spayed females).

PROCEDURES Ferrets were anesthetized. A balloon occlusion catheter was introduced through a jugular vein, passed into the CVC by use of fluoroscopy, positioned cranial to the right renal vein, and inflated for 20 minutes. Venography was performed 5 and 15 minutes after occlusion. Pressure in the CVC caudal to the occlusion was measured continuously. A CBC, plasma biochemical analysis, and urinalysis were performed immediately after the procedure and 2 or 3 days later.

RESULTS All 8 ferrets survived the procedure; no differences were apparent between the sexes. Vessels providing collateral circulation were identified in all ferrets, indicating blood flow to the paravertebral venous plexus. Complications observed prior to occlusion included atrial and ventricular premature contractions. Complications after occlusion included bradycardia, seizures, and extravasation of contrast medium. Mean baseline CVC pressure was 5.4 cm H2O. During occlusion, 6 ferrets had a moderate increase in CVC pressure (mean, 24.3 cm H2O) and 2 ferrets had a marked increase in CVC pressure to > 55.0 cm H2O.

CONCLUSIONS AND CLINICAL RELEVANCE Caval occlusion for 20 minutes was performed in healthy ferrets with minimal adverse effects noted within the follow-up period and no apparent differences between sexes. The CVC pressure during occlusion may be prognostic in ferrets undergoing surgical ligation of the CVC, which commonly occurs during adrenal tumor resection.

Full access
in American Journal of Veterinary Research