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in Journal of the American Veterinary Medical Association



To develop a test for detection of Haemobartonella felis, using a polymerase chain reaction (PCR) assay.


4 adult cats seronegative for FeLV and feline immunodeficiency virus.


Cats were infected with H felis by IV administration of 1 ml of blood obtained from an infected cat. Rectal temperature, PCV, and microscopic examination of blood smears for organisms were monitored daily. At peak of infection, doxycycline treatment was initiated for 21 days. Blood samples were collected at weekly intervals. Six months after treatment, 2 cats were given methylprednisolone (14 mg/kg of body weight, IM). Daily blood samples were collected for CBC, detection of organisms, and PCR evaluation. On the basis of the 16S rRNA gene sequence of H felis,specific PCR primers were created for a 393-basepair internal fragment.


The 393-basepair product was consistently amplified from blood samples obtained during peak parasitemia but not during the last week of or immediately after completion of doxycycline treatment. After treatment, PCV returned to the reference range, and organisms were not observed in blood samples; however, the PCR product could be consistently amplified. After administration of methylprednisolone, organisms were only rarely observed in blood smears but were consistently detected by PCR analysis.

Clinical Relevance

Using PCR analysis, it was possible to detect H felisin blood samples obtained from cats during peak parasitemia, during most of the carrier phase, and after challenge with immunosuppressive drugs. During and immediately after antibiotic treatment, this test may fail to detect the organisms. (Am J Vet Res1998;59:1215–1220)

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in American Journal of Veterinary Research


OBJECTIVE To develop and validate a real-time quantitative PCR (qPCR) assay for the detection and quantification of Mycoplasma ovis in goats and investigate the prevalence and risk factors for hemoplasma infection of goats located in Indiana.

ANIMALS 362 adult female goats on 61 farms.

PROCEDURES Primers were designed for amplification of a fragment of the dnaK gene of M ovis by use of a qPCR assay. Blood samples were collected into EDTA-containing tubes for use in total DNA extraction, blood film evaluation, and determination of PCV. Limit of detection, intra-assay variability, interassay variability, and specificity of the assay were determined.

RESULTS Reaction efficiency of the qPCR assay was 94.45% (R2, 0.99; slope, −3.4623), and the assay consistently detected as few as 10 copies of plasmid/reaction. Prevalence of infection in goats on the basis of results for the qPCR assay was 18.0% (95% confidence interval, 14% to 22%), with infected goats ranging from 1 to 14 years old, whereby 61% (95% confidence interval, 47% to 73%) of the farms had at least 1 infected goat. Bacterial load in goats infected with M ovis ranged from 1.05 × 103 target copies/mL of blood to 1.85 × 105 target copies/mL of blood; however, no bacteria were observed on blood films. Production use of a goat was the only risk factor significantly associated with hemoplasma infection.

CONCLUSIONS AND CLINICAL RELEVANCE The qPCR assay was more sensitive for detecting hemoplasma infection than was evaluation of a blood film, and production use of a goat was a risk factor for infection.

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


Objective—To determine reference ranges for results of hematologic analyses of healthy Belgian Tervuren, to compare results of hematologic analyses for healthy Belgian Tervuren with results for healthy dogs of other breeds, and to determine prevalence of physiologic leukopenia in Belgian Tervuren.

Design—Cohort study.

Animals—180 healthy Belgian Tervuren and 63 healthy dogs of other breeds.

Procedure—Blood samples were analyzed by use of an automated device. Reference ranges were calculated for Belgian Tervuren by use of standard methods.

Results—Total WBC counts of Belgian Tervuren ranged from 2.61 to 16.90 X 103/µl. Mean WBC count of Belgian Tervuren (mean ± SEM, 7.04 ± 0.16 X 103/µl) was significantly lower than mean count for control dogs. Significantly more Belgian Tervuren (65/180; 36%) than control dogs (2/63; 3%) had WBC counts < 6.00 X 103/µl. Percentage of Belgian Tervuren with WBC count < 6.00 X 103/µl was low for dogs ≤ 2 years old, increased sharply for dogs between 2 and 4 years old, and was approximately 65% for dogs > 4 years old. Neutrophil, lymphocyte, and monocyte counts were significantly lower, and RBC count, hematocrit, and eosinophil fraction were significantly higher in Belgian Tervuren than in control dogs.

Conclusions and Clinical Relevance—Results suggest that physiologic leukopenia, resulting from low numbers of neutrophils, lymphocytes, and monocytes, may be a typical finding in a large percentage of healthy Belgian Tervuren and is not of clinical importance in otherwise healthy dogs. Healthy Belgian Tervuren may also have RBC counts and hematocrits higher than expected for healthy dogs.( J Am Vet Med Assoc 2000;216:866–871)

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in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association


Objective—To characterize clinical signs, clinicopathologic features, treatments, and survival in dogs with naturally acquired foodborne aflatoxicosis.

Design—Retrospective case series.

Animals—72 dogs that consumed aflatoxin-contaminated commercial dog food.

Procedures—Medical records of affected dogs were reviewed. Between December 2005 and March 2006, dogs were identified as having foodborne aflatoxin hepatotoxicosis on the basis of the history of consumption of contaminated food or characteristic histopathologic lesions (subject dog or a recently deceased dog in the same household or kennel). Recorded information included signalment, clinical features, clinicopathologic test results, treatments, and survival. Data were analyzed by survival status.

Results—Most dogs were of large breeds from breeding kennels. No significant differences were found in age or weight between 26 (36%) survivor dogs and 46 (64%) nonsurvivor dogs. Severity of clinical signs varied widely; 7 dogs died abruptly. In order of onset, clinical features included anorexia, lethargy, vomiting, jaundice, diarrhea (melena, hematochezia), abdominal effusion, peripheral edema, and terminal encephalopathy and hemorrhagic diathesis. Common clinicopathologic features included coagulopathic and electrolyte disturbances, hypoproteinemia, increased serum liver enzyme activities, hyperbilirubinemia, and hypocholesterolemia. Cytologic hepatocellular lipid vacuolation was confirmed in 11 dogs examined. In comparisons of clinicopathologic test results between survivor and nonsurvivor dogs, only granular cylindruria (7/21 dogs) consistently predicted death. Best early markers of aflatoxicosis were low plasma activities of anticoagulant proteins (protein C, antithrombin) and hypocholesterolemia. Despite aggressive treatment, many but not all severely affected dogs died.

Conclusions and Clinical Relevance—Serum liver enzyme activities and bilirubin concentration were unreliable early markers of aflatoxin hepatotoxicosis in dogs. Hypocholesterolemia and decreased plasma protein C and antithrombin activities may function as exposure biomarkers.

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in Journal of the American Veterinary Medical Association