Collateral circulation in ferrets (Mustela putorius) during temporary occlusion of the caudal vena cava.

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.

Bilateral traumatic temporomandibular joint luxation in a rat.

Bilateral temporomandibular joint (TMJ) luxation was diagnosed postmortem in a female, 6-mo-old CD rat (Rattus norvegicus) after probable head entrapment and subsequent disentanglement from a protective jacket. Clinical antemortem signs included inability to close her mouth, prehend food and drink water, anxiety, and linear skin erosions extending down the right and left commissures of the mouth. Radiography revealed rostral displacement of the mandible with concomitant malocclusion. The combination of clinical signs, acute nature of the presentation, and torn appearance of the protective jacket were strongly indicative of a traumatic etiology. To our knowledge, this is the first reported case of TMJ luxation in a rat.

Selected complete blood cell count and plasma protein electrophoresis parameters in pet psittacine birds evaluated for illness.

Veterinarians rely on results of both the complete blood cell count (CBC) and plasma protein electrophoresis (EPH) in conjunction with the results of the plasma biochemical analysis to evaluate the health status of avian patients. Because the CBC and protein EPH measure different aspects of the immune response to disease, both tests are recommended in avian patients to rule out infectious or inflammatory disease. To evaluate results of the CBC and protein EPH in pet psittacine birds, the records of 144 pet psittacine birds, comprising 11 genera, that were presented for suspected illness were reviewed. Results of the CBC (total white blood cell count and packed cell volume) and protein EPH (alpha, beta, and gamma globulin concentrations) from submitted blood samples from each bird were evaluated. Of the 144 birds, 63 (43.8%) had abnormal CBC results, and 25 (17.4%) had abnormal EPH measurements. Results of the CBC and protein EPH were within reference ranges in 73 birds (50.7%). Abnormal results of the CBC in conjunction with normal EPH results were present in 46 birds (31.9%), compared with 8 birds (5.6%) with normal results of the CBC and abnormal EPH results. The findings of this study could aid practitioners in evaluating psittacine patients and prioritizing the value of individual diagnostic tests.

Evaluation of mucosal and seborrheic sites for staphylococci in two populations of captive psittacines.

OBJECTIVE: To survey 2 populations of psittacines to characterize Staphylococcus spp isolated from commensal cutaneous microflora. DESIGN: Prospective cross-sectional study. ANIMALS: 107 psittacine birds from a sanctuary and 73 psittacine birds in private households or a pet store. PROCEDURES: Gram-positive, catalase-positive cocci isolated from mucosal and seborrheic sites were speciated, and pulsed-field gel electrophoresis was performed on coagulase-positive isolates. A bird was classified as having positive results when at least 1 sample site yielded positive results for at least 1 staphylococcal species. RESULTS: 89 of 180 (49.4%) birds had positive results for staphylococci at the carriage sites sampled. Privately owned birds were twice as likely to have positive results for staphylococci as were sanctuary birds (71% vs 35%). Coagulase-positive staphylococci were significantly more common in the sanctuary birds (47% vs 1%). Staphylococcus intermedius was significantly more common in the sanctuary birds (46% vs 2%). Staphylococcus hominis subsp hominis and Staphylococcus epidermidis, coagulase-negative staphylococci associated with humans, were significantly more common in pet birds. Cockatoos were twice as likely to have positive results for staphylococci as were other genera. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that staphylococcal colonization in captive psittacines was less common than in other species studied. Staphylococci isolated from a pet psittacine may reflect that of the humans and other animals with which the bird lives in close proximity; however, further studies are needed to evaluate the effects exposure to humans may have on the microflora of these birds.

Methicillin-resistant Staphylococcus aureus-associated dermatitis in a Congo African grey parrot (Psittacus erithacus erithacus).

A 2-year-old DNA-sexed female Congo African grey parrot (Psittacus erithacus erithacus) was evaluated for self-trauma of the feathers and skin of the tail base for a duration of more than 1 year. All rectrices and tail coverts were missing, the skin of the tail base was thickened and ulcerated, and the uropygial gland was swollen. Results of a complete blood cell count revealed relative monocytosis and basophilia. Survey radiographs showed truncation and lysis of the caudal vertebrae and pygostyle. Results of biopsy and bacterial culture of the tail base lesions revealed an ulcerative bacterial dermatitis positive for staphylococcal cassette chromosome mec (SCCmec) type IV (community-acquired) methicillin-resistant Staphylococcus aureus (MRSA). The bird was treated with oral trimethoprim-sulfamethoxazole, meloxicam, fluoxetine, topical lidocaine gel, and hydrotherapy. One month later, tail feather regrowth was evident; however, follow-up over 2 years found continued self-trauma to the rectrices in spite of repeated skin biopsies negative for MRSA or other bacteria. It is unknown if the MRSA cultured from this bird was commensal or acquired from either the environment or humans to which the bird was exposed.

Infiltrative lipoma in a blue-crowned conure (Aratinga acuticaudata).

A 14-year-old blue-crowned conure (Aratinga acuticaudata) of unknown sex was brought to the hospital with a 3-week history of straining and vocalizing during defecation. Physical examination revealed blood and urate staining on feathers around the cloaca. A 2.5-cm subcutaneous swelling was palpated along the midline of the caudoventral abdomen. During surgical exploratory, a subcutaneous soft-tissue mass was found, which extended through the body wall musculature and into the coelomic cavity. The abnormal tissue was adhered to the cloacal serosa, causing deviation of the cloaca caudally and ventrally. The mass was excised and submitted for histopathology, and the histopathologic diagnosis was infiltrative lipoma. The surgical incision healed uneventfully, and no evidence of tumor regrowth was apparent 7 months after surgery. This is the first documented case of infiltrative lipoma in a bird.

Assessment of a point-of-care biochemical analyzer and comparison with a commercial laboratory for the measurement of total protein and albumin concentrations in psittacines.

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.

Immune-mediated hemolytic anemia in an eclectus parrot.

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.

Plasma biochemical reference intervals for koi.

OBJECTIVE: To assess reproducibility of an in-house tabletop biochemical analyzer for measurement of plasma biochemical analytes and establish reference intervals in adult koi. DESIGN: Prospective study. ANIMALS: 71 healthy adult koi. PROCEDURES: Plasma was analyzed for concentrations or activities of albumin, alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, bile acids, BUN, calcium, cholesterol, creatine kinase, gamma-glutamyltransferase, globulin, glucose, K, Na, P, total bilirubin, total protein, and uric acid. Duplicate samples were evaluated by use of the intraclass correlation coefficient to determine reproducibility. To assess the magnitude of differences between replicate samples, the absolute mean difference, SD, and minimum and maximum values were calculated for each analyte. Median values and reference intervals were calculated. RESULTS: Intraclass correlation coefficient values were excellent for all analytes except alanine aminotransferase (good), Na (poor), gamma-glutamyltransferase (poor), and P (poor). Reference intervals were established. CONCLUSIONS AND CLINICAL RELEVANCE: The in-house tabletop biochemical analyzer had good precision for measuring most plasma biochemical analytes. Further research and comparison with other reference procedures are needed before reference intervals and precision can be established for globulin, Na, P, K, and albumin. Aquatic veterinarians may be able to use the reference intervals for adult koi as an important diagnostic tool or as part of a fish wellness program, as commonly done in other domestic species.

Distribution of Malassezia organisms on the skin of unaffected psittacine birds and psittacine birds with feather-destructive behavior.

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-cm(2) 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.

Psittacine plasma concentrations of elements: daily fluctuations and clinical implications.

During the past 2 decades, the potential for excessive exposure of pet birds to zinc has become a concern for many pet bird owners. Ideally, avian zinc toxicosis is diagnosed on the basis of history of exposure to zinc, radiographic evidence of ingested metal, occurrence of melena, detection of an elevated plasma zinc concentration, and response to treatment. However, most pet birds suspected of having zinc toxicosis present with vague signs and lack of radiographic evidence; therefore, the diagnosis relies on the presence of an elevated plasma zinc concentration. A question was, is there a significant diurnal variation in the zinc concentration in psittacine birds and could this be clinically relevant? Because studies in other species have shown that zinc is not the only element that shows a diurnal variation, the authors examined 13 other plasma elements including arsenic, cadmium, calcium, cobalt, copper, iodine, iron, magnesium, manganese, molybdenum, potassium, selenium, and total phosphorus. Fifteen adult psittacine birds housed in the same aviary were used in this study. Three blood samples, separated by 4 hours, were taken from the right jugular vein in each bird. All elements were measured in plasma. Zinc, copper, and molybdenum revealed diurnal fluctuations. The results of this study suggest that interpretation of clinical samples may be more complicated than previously believed. Furthermore, on the basis of the results of this study, it is possible that some avian reference ranges may need to be reexamined.

Assessment of the reliability of plasma electrophoresis in birds.

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, alpha1-, alpha2-, beta-, and gamma-globulin concentrations, the intraclass correlation coefficient (r(i)) 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, alpha1-, alpha2-, beta-, and gamma-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.