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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

Objective—To determine effects of oral administration of metronidazole on the number and species of duodenal bacteria and selective nutrients of cats.

Animals—6 healthy domestic shorthair cats.

Procedure—Undiluted duodenal fluid was obtained for quantitative and qualitative bacterial culture to determine species and number of bacteria in healthy cats. Blood samples were assayed for taurine, total protein, albumin, cobalamin, and folate concentrations. Cats then were given metronidazole (20 mg/kg of body weight, PO, q 12 h) for 1 month, after which bacterial cultures and serum assays of nutrients were repeated. Nine months after cessation of antibiotic treatment, duodenal bacteria were re-evaluated and serum was assayed for total protein, albumin, cobalamin, and folate concentrations.

Results—Oral administration of metronidazole caused a significant decrease in aerobic and anaerobic bacterial counts in the duodenum of healthy cats, accompanied by emergence of Streptococcus spp and Corynebacterium spp. Serum concentrations of cobalamin and albumin increased when duodenal bacterial counts were decreased, although changes in folate or taurine concentrations were not detected. Measured variables did not differ, when comparing results obtained before and 9 months after cessation of metronidazole.

Conclusions and Clinical Relevance—Oral administration of metronidazole decreased the number of aerobic bacteria and altered indigenous flora in the small bowel of cats. Normal duodenal flora appeared to be stable, because species of bacteria were reestablished by 9 months after cessation of metronidazole. Bacterial flora appeared to have an impact on nutrients, because albumin and cobalamin increased during antibiotic administration and returned to preadministration concentrations after cessation of the antimicrobial. (Am J Vet Res 2000;61:1106–1112)

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in American Journal of Veterinary Research

Abstract

Objective—To evaluate intestinal permeability and absorption in healthy cats in association with diet and normal intestinal microflora.

Animals—6 healthy domestic shorthair cats.

Procedure—A sugar solution containing D-xylose, 3- 0-methyl-D-glucose, L-rhamnose, lactulose, and 51Cr- EDTA was administered intragastrically to healthy cats, and urinary excretion of ingested sugars was determined 5 hours after administration. After the same cats had received metronidazole for 1 month, the study was repeated. A final study was performed while cats were maintained on a new diet differing in composition and processing.

Results—Lactulose-to-rhamnose ratios, reflecting intestinal permeability, were higher in cats, compared with values for humans or dogs, and values obtained before and after metronidazole administration (mean ± SEM; before, 0.40 ± 0.08; after, 0.45 ± 0.09) were not significantly different. Intestinal absorption also was unaltered after antibiotic administration, and the xylose-to-glucose ratio was 0.70 ± 0.03 before and 0.71 ± 0.06 after metronidazole administration. Sugar recovery did not differ significantly while cats were maintained on canned or dry food.

Conclusions and Clinical Relevance—Reference ranges were established for the percentage urinary recovery of orally administered D-xylose, 3-0-methyl-Dglucose, L-rhamnose, lactulose, and 51Cr-EDTA obtained after 5 hours in healthy cats. The intestines of cats appear to be more permeable than those of other species, although the normal bacterial microflora does not appear to influence the integrity or function of the feline intestine, because values obtained for the measured variables before or after antibiotic administration were not significantly different. In addition, differences were not detected when the diet was completely altered. ( Am J Vet Res 2001;62:111–118)

Full access
in American Journal of Veterinary Research

Abstract

Objective—To determine whether metal concentrations in canine liver specimens were influenced by specimen size, assay variability, tissue processing (formalin fixation and deparaffinization), or storage in paraffin blocks.

Sample Population—Liver specimens (fresh frozen and deparaffinized) from 2 dogs with chronic hepatitis (high copper but unremarkable iron concentration [liver 1] and unremarkable copper but high iron concentration [liver 2]) as well as fresh and deparaffinized-archived liver specimens from 20 dogs with various hepatopathies.

Procedures—Fresh frozen liver specimens (obtained via simulated needle-core and wedge biopsy), fresh hepatic tissue, and deparaffinized-archived specimens (0.5 to 14 years old) were analyzed for concentrations of copper, iron, and zinc by atomic absorption flame spectrometry. Clinical severity scores were assigned on the basis of tissue metal concentrations.

Results—Interassay variation of metal standards was < 4%. Measurements of liver tissues on 8 consecutive days yielded high coefficients of variation (3.6% to 50%) reflecting heterogenous histologic metal distribution; variation was highest in liver 1 and deparaffinized-archived tissues. Heterogenous metal distribution was confirmed by histologic evaluation. The largest range of metal concentrations was detected in wedge biopsy specimens. In tissues with high metal concentrations, copper and iron concentrations were significantly lower in needle-core versus wedge biopsy specimens. A higher zinc concentration in deparaffinized-archived specimens masked a low zinc concentration in fresh liver tissue of 10 of 20 (50%) dogs.

Conclusions and Clinical Relevance—Retrospective measurement of copper and iron concentrations but not zinc concentrations in deparaffinized-archived liver specimens provided relevant information. The value of needle-core biopsy specimens for measurement of metal concentrations is questionable.

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.

Full access
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.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate differences in hepatic copper concentrations in Labrador Retrievers with and without chronic hepatitis.

Design—Retrospective case-control study.

Sample—Liver tissue specimens from 36 Labrador Retrievers with chronic hepatitis and 36 age- and sex-matched Labrador Retrievers without chronic hepatitis (control dogs).

Procedures—Liver tissue specimens were obtained during 2 study periods (1980 to 1997 and 1998 to 2010). For each tissue specimen, a histologic score was assigned independently by each of 2 interpreters, and the hepatic copper concentration was qualitatively determined via rhodanine staining and quantitatively determined via atomic absorption spectroscopy.

Results—Mean hepatic copper concentration was significantly higher in dogs with chronic hepatitis (614 μg/g of dry weight [range, 104 to 4,234 μg/g of dry weight]), compared with that in control dogs (299 μg/g of dry weight [range, 93 to 3,810 μg/g of dry weight]), and increased significantly over time. A higher proportion of liver tissue specimens collected during the 1998–2010 study period had hepatic copper concentrations > 400 μg/g of dry weight (the upper limit of the reference range), compared with the proportion of liver tissue specimens collected during the 1980–1997 study period. The qualitative copper score did not accurately predict quantitative hepatic copper concentration in 33% of study dogs.

Conclusions and Clinical Relevance—Results suggested that the increase in hepatic copper concentrations in Labrador Retrievers with and without chronic hepatitis over time may be the result of increased exposure of dogs to environmental copper, most likely via the diet.

Full access
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

Abstract

Objective—To determine whether a colony environment predisposes healthy cats to high bacterial counts, including counts of obligate anaerobes, in the duodenum and whether increased numbers of bacteria could be found in the duodenum of cats with signs of chronic gastrointestinal tract disease.

Design—Prospective study.

Animals—20 healthy control cats (10 from a colony environment and 10 pet cats) and 19 cats with a history of chronic gastrointestinal tract disease.

Procedure—Undiluted duodenal fluid was quantitatively and qualitatively assessed by bacteriologic culture under aerobic and anaerobic conditions. Serum concentrations of cobalamin and folate were also measured.

Results—Significant differences were not detected in the numbers of bacteria found in the duodenum of cats housed in a colony environment, compared with pet cats fed an identical diet prior to sampling. All healthy cats were, therefore, combined into 1 control group. Compared with healthy cats, cats with clinical signs of gastrointestinal tract disease had significantly lower counts of microaerophilic bacteria, whereas total, anaerobic, and aerobic bacterial counts were not significantly different. None of the cats with disease had total bacterial counts higher than expected from the range established in the control cats. Differences were not detected in regard to serum folate or cobalamin concentrations between diseased and healthy cats.

Conclusions and Clinical Relevance—These findings indicated that healthy colony cats and pet cats have high numbers of bacteria in the duodenum, including high numbers of obligate anaerobes. Our findings also suggest that bacterial overgrowth in the small intestine is not a common clinical syndrome in cats with chronic nonobstructive gastrointestinal tract disease. ( J Am Vet Med Assoc 2001;218:48–51)

Full access
in Journal of the American Veterinary Medical Association