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- Author or Editor: Cheri A. Johnson x
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Abstract
Objective—To investigate the duration of dark-adaptation time required for recovery of electroretinographic responses after fundus photography or indirect ophthalmoscopy in dogs.
Animals—6 dogs.
Procedure—Initially, scotopic-intensity series of electroretinograms (ERGs) were recorded after 20 minutes of dark adaptation. The fundus of the left eye of each dog was photographed (n = 10) or examined via indirect ophthalmoscopy for 5 minutes with moderate- (117 candela [cd]/m2) or bright-intensity (1,693 cd/m2) light; ERGs were repeated after a further 20 or 60 minutes of dark adaptation (6 procedures/dog).
Results—Following 20 minutes of dark adaptation after fundus photography, the b- and a-wave amplitudes were reduced in response to brighter stimuli, compared with pretest ERGs; after 60 minutes of dark adaptation, ERG amplitudes had recovered. Following 20 minutes of dark adaptation after indirect ophthalmoscopy (moderate-intensity light), significantly lower b-wave amplitudes were recorded in response to 2 of the brighter flash stimuli, compared with pretest ERGs; after 60 minutes of dark adaptation, ERG amplitudes had recovered. Following 20 minutes of dark adaptation after indirect ophthalmoscopy (bright-intensity light), all ERG amplitudes were significantly decreased and implicit times were significantly decreased at several flash intensities, compared with pretest ERGs; after 60 minutes of dark adaptation, ERG amplitudes and implicit times had returned to initial values, except for b-wave amplitudes recorded in response to dimmer stimuli.
Conclusions and Clinical Relevance—Results suggest that at least 60 minutes of dark adaptation should be allowed before ERGs are performed in dogs after fundus photography or indirect ophthalmoscopy. (Am J Vet Res 2005;66:1798–1804)
Abstract
Objective—To determine the effect of semen in urine specimens on urine protein concentration measured by means of dipstick analysis.
Sample Population—14 urine samples from 3 adult castrated male dogs and 14 semen samples from 7 adult sexually intact male dogs.
Procedures—Serial dilutions of the whole ejaculate or spermatozoa-free seminal fluid in urine were created, and unaltered and diluted urine samples were analyzed by means of a commercially available dipstick; pH and specific gravity of the samples were also measured. Spermatozoa and WBC counts of the semen samples and protein concentration of the seminal fluid were determined.
Results—Protein concentrations determined by means of dipstick analysis of urine samples to which whole ejaculate (dilutions of 1:1, 1:2, 1:16, 1:64, and 1:256) or seminal fluid (dilutions of 1:1, 1:2, 1:16, and 1:64) had been added were significantly higher than concentrations in unaltered urine samples. All 13 samples to which whole ejaculate was added at a dilution of 1:2 and 10 of 12 samples to which seminal fluid was added at a dilution of 1:2 were positive for blood on dipstick analysis. There was no significant linear correlation between spermatozoa or WBC count of the semen sample and protein concentration of the spermatozoa-free seminal fluid.
Conclusions and Clinical Relevance—Results suggested that regardless of whether spermatozoa were present, semen contamination could result in false-positive results for protein and blood during dipstick analysis of urine samples from sexually intact male dogs.
Abstract
Objective—To compare accuracy of estimates of cystolith size obtained by means of plain radiography, double-contrast cystography, ultrasonography, and computed tomography.
Sample Population—30 canine cystoliths ranging from 1 to 11 mm in diameter with various mineral compositions.
Procedures—A bladder phantom model was created by filling a rubber balloon with saline (1% NaCl) solution and positioning it on top of a 2% gelatin cushion at the bottom of a water-filled 4-quart container. Cystoliths were individually placed in the bladder phantom and imaged by each of the 4 techniques. For each image, cystolith size was measured by 2 radiologists with computerized calipers, and size estimates were compared with actual cystolith size.
Results—Mean cystolith size estimates obtained by means of radiography, cystography, and computed tomography did not differ significantly from each other. However, for ultrasonographic images, mean ± SD difference between actual and estimated cystolith size (2.95 ± 0.73 mm) was significantly higher than mean difference for radiographic, cystographic, and computed tomographic images. For ultrasonography, mean ± SD percentage overestimation in cystolith size was 68.4 ± 51.5%.
Conclusions and Clinical Relevance—Results indicated that measurements of cystolith size obtained by means of ultrasonography may overestimate the true size. This suggests that cystolith size estimates obtained by means of ultrasonography should be interpreted with caution whenever cystolith size may influence patient management.
Abstract
OBJECTIVE To estimate Brucella canis seropositivity rates for purebred dogs being bred by noncommercial breeders, describe epidemiological findings in infected commercial dog-production facilities, and characterize B canis infection in pet dogs and the risk to human health.
DESIGN Retrospective descriptive study.
SAMPLE 2,799 canine specimens submitted to the Michigan State University Veterinary Diagnostic Laboratory for B canis testing and records of B canis reports provided to the Michigan Department of Agriculture and Rural Development from 2007 through 2016.
PROCEDURES Results of B canis laboratory tests and epidemiological findings for reported cases of B canis were reviewed and summarized. Federal and state public health officials were interviewed regarding human B canis infection. State veterinarians were interviewed regarding canine brucellosis reporting and control procedures.
RESULTS Estimated B canis seropositivity was 0.4% among purebred Michigan dogs owned by noncommercial breeders. Infection was confirmed in dogs from 17 commercial dog-production facilities, 3 shelters, and 1 rescue agency. Estimated infection prevalence in production facilities ranged from 2 of 22 (9%) to 5 of 6 (83%). Transfer of infected dogs involved 22 Michigan counties and 11 states. Seven of 20 privately owned infected dogs had diskospondylitis; I also had uveitis. Fifty-three veterinary hospital or diagnostic laboratory personnel had inadvertent exposure to the pathogen. Brucella canis was isolated from 1 commercial production facility owner.
CONCLUSIONS AND CLINICAL RELEVANCE B canis was uncommon in purebred dogs being bred by noncommercial breeders but endemic in Michigan commercial facilities producing dogs destined to become household pets. Infected pet dogs caused human B canis exposure, and several pet dogs had debilitating disease not associated with the reproductive system.
Abstract
Objective—To determine whether Scottish Terriers have higher serum alkaline phosphatase (ALP) activities and a higher prevalence of diseases commonly associated with high serum ALP activity than do dogs of other breeds.
Design—Retrospective case-control study.
Animals—85 Scottish Terriers and 340 age-matched control dogs that were not Scottish Terriers.
Procedure—Medical records were reviewed, and data for year of evaluation, age, sex, breed, serum ALP activity, and final diagnosis were recorded.
Results—Scottish Terriers had a significantly higher mean serum ALP activity than did control dogs (1,520 U/L vs 306 U/L). Regardless of breed, dogs that had a disease commonly associated with high serum ALP activity had a significantly higher mean serum ALP activity than did dogs without such diseases (1,304 U/L vs 427 U/L). Scottish Terriers were 2.4 times as likely to have a disease commonly associated with high serum ALP activity than were control dogs, but Scottish Terriers with diseases commonly associated with high serum ALP activity had a significantly higher mean ALP activity than did control dogs with such diseases (2,073 U/L vs 909 U/L), and Scottish Terriers without such diseases had a significantly higher mean serum ALP activity than did control dogs without such diseases (1,349 U/L vs 228 U/L).
Conclusions and Clinical Relevance—Results suggest that Scottish Terriers have higher serum ALP activities than do dogs of other breeds. Although Scottish Terriers also have a higher prevalence of diseases associated with high serum ALP activity, this alone did not explain the higher mean serum ALP activity in the breed.
Abstract
OBJECTIVE To document clinical signs in cats and dogs with Cuterebra infection, determine the outcome of infected animals, and determine whether Yorkshire Terriers were more commonly affected than other breeds of dogs.
DESIGN Retrospective case series.
ANIMALS 22 cats and 20 dogs with Cuterebra infection.
PROCEDURES Medical records of dogs and cats with Cuterebra infection were reviewed for signalment, history, clinical and laboratory findings, treatment, duration of hospitalization, and outcome.
RESULTS Most (16/20 [80%]) of the dogs weighed ≤ 4.5 kg (10 lb), and Yorkshire Terriers were overrepresented (8/20 [40%]), compared with dogs of other breeds. Ten (50%) dogs and 3 (14%) cats had systemic inflammatory response syndrome at the time of initial evaluation, and 8 (40%) dogs but none of the cats had disseminated intravascular coagulation. The overall mortality rate was 17% (7/42), but was higher for dogs (6/20 [30%]) than cats (1/22 [4.5%]). All 6 dogs that died weighed ≤ 4.5 kg and had systemic inflammatory response syndrome, disseminated intravascular coagulation, or both.
CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that Cuterebra infection can cause severe systemic illness in small-breed dogs. Yorkshire Terriers were more commonly affected than were dogs of other breeds and, subjectively at least, appeared to be more likely to develop severe systemic illness.