Search Results

You are looking at 1 - 8 of 8 items for

  • Author or Editor: Linda S. Mansfield x
  • Refine by Access: All Content x
Clear All Modify Search

Abstract

Objective—To determine prevalence of Dirofilaria immitis infection among shelter cats.

Design—Cross-sectional study.

Animals—239 cats euthanatized at an animal shelter in southeastern Michigan.

Procedure—A gross necropsy focusing on the thoracic cavity, heart, lungs, and pulmonary vessels was performed within 5 hours after cats were euthanatized. Blood was collected directly from the heart of cats found to be infected and tested, using a filter test for microfilariae. Serum was tested for D immitis antigens by use of 2 antigen detection kits and for D immitis-specific antibodies by use of 2 antibody detection kits.

Results—Cats ranged from approximately 4 months to 15 years old. Adult D immitis were found in 6 (2.5%) cats. Blood could not be recovered from 1 of the cats with heartworm infection. For the 5 other cats, results of the filter test were negative, and results of both antigen and both antibody tests were positive.

Conclusions and Clinical Relevance—Results suggest that cats living in an urban area in the northern part of the United States have a low prevalence of adult D immitis infection. However, this is likely to be an underestimate of the true prevalence of infection, because no attempts were made to identify cats infected with larval or juvenile stages of D immitis. (J Am Vet Med Assoc 2000;217:211–212)

Restricted access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine seroprevalence of antibodies against Leishmania spp among dogs other than Foxhounds in the United States.

Design—Cross-sectional study.

Sample Population—957 serum samples from dogs throughout the United States submitted between January 2000 and August 2001 to the Diagnostic Center for Population and Animal Health at Michigan State University for serologic testing for tick-borne diseases.

Procedure—Samples were tested for antibodies against Leishmania spp with an immunofluorescent antibody (IFA) assay. Samples with positive results were submitted to the Centers for Disease Control and Prevention for confirmatory testing.

Results—Results of the IFA assay were negative for 939 of 957 samples. For 16 samples, titers were from 1:16 to 1:64, and titers in these dogs were considered likely to be a result of cross-reactivity with antibodies directed against other organisms. For the remaining 2 samples, the titers were ≥ 1:128. One of these samples was from a blood donor dog that had never had any clinical signs of leishmaniasis. Followup samples from both dogs also had Leishmania IFA titers ≥ 1:128. Both dogs had antibodies against Trypanosoma cruzi, as determined with a radioimmunoprecipitation assay.

Conclusions and Clinical Relevance—Results suggested that the seroprevalence of antibodies against Leishmania spp in dogs in the United States was low. However, results further suggested that leishmaniasis may not be limited to Foxhounds in the United States. (J Am Vet Med Assoc 2003;222:603–606)

Restricted access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate dogs as a sentinel species for emergence of Lyme disease in a region undergoing invasion by Ixodes scapularis.

Sample Population—353 serum samples and 78 ticks obtained from dogs brought to 18 veterinary clinics located in the lower peninsula of Michigan from July 15, 2005, through August 15, 2005.

Procedures—Serum samples were evaluated for specific antibodies against Borrelia burgdorferi by use of 3 serologic assays. Ticks from dogs were subjected to PCR assays for detection of pathogens.

Results—Of 353 serum samples from dogs in 18 counties in 2005, only 2 (0.6%) contained western blot analysis–confirmed antibodies against B burgdorferi. Ten of 13 dogs with I scapularis were from clinics within or immediately adjacent to the known tick invasion zone. Six of 18 I scapularis and 12 of 60 noncompetent vector ticks were infected with B burgdorferi. No ticks were infected with Anaplasma phagocytophilum, and 3 were infected with Babesia spp.

Conclusions and Clinical Relevance—Serosurvey in dogs was found to be ineffective in tracking early invasion dynamics of I scapularis in this area. Tick chemoprophylaxis likely reduces serosurvey sensitivity in dogs. Ticks infected with B burgdorferi were more common and widely dispersed than seropositive dogs. In areas of low tick density, use of dogs as a source of ticks is preferable to serosurvey for surveillance of emerging Lyme disease. Impact for Human Medicine—By retaining ticks from dogs for identification and pathogen testing, veterinarians can play an important role in early detection in areas with increasing risk of Lyme disease.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate 2 rapid, patient-side assays for detection of Cryptosporidium parvum in feces from neonatal calves with diarrhea.

Design—Diagnostic test evaluation.

Sample Population—Fecal samples from 96 neonatal (1 to 30 days old) calves with diarrhea.

Procedure—Results of the rapid assays were compared with results of microscopic examination of fecal smears that had been stained with diamant fuchsin stain.

Results—One of the rapid assays correctly identified 56 of 62 (90%) fecal samples positive for C parvum oocysts and 33 of 34 (97%) fecal samples negative for oocysts. The other assay correctly identified 53 of 62 (85%) fecal samples positive for oocysts and 33 of 34 (97%) fecal samples negative for oocysts.

Conclusions and Clinical Relevance—Results suggest that these 2 rapid assays are accurate when used to detect C parvum in fecal samples from neonatal calves with diarrhea. ( J Am Vet Med Assoc 2004;225:1090–1092)

Restricted access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine apparent seroprevalence of antibodies against Sarcocystis neurona in a population of domestic cats previously tested for antibodies against Toxoplasma gondii.

Design—Cross-sectional study.

Sample Population—Serum from 196 domestic cats.

Procedure—Banked serum samples submitted to the Michigan State University Animal Health Diagnostic Laboratory for T gondii diagnostic testing were tested for antibodies against S neurona by use of an indirect fluorescent antibody (IFA) test and a western blot test. Submission records were analyzed to determine descriptive statistics and test for associations between positive results of a test for S neurona and other variables in the data set.

Results—10 of 196 (5%) samples yielded positive results for antibodies against S neurona by use of western blot analysis, whereas 27 samples yielded positive results by use of the IFA. No association was found between S neurona western blot test results and T gondii test results, age, sex, or the reason for T gondii testing. The S neurona IFA titer was positively and significantly associated with positive results of western blot analysis.

Conclusions and Clinical Relevance—Domestic cats are not likely to play a substantial role as intermediate hosts in the natural life cycle of S neurona. Results indicate that natural infection of domestic cats may occur, and small animal practitioners should be aware of this fact when evaluating cats with neurologic disease. The S neurona IFA test had lower specificity than western blot analysis. (J Am Vet Med Assoc 2002;220:511–514)

Restricted access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine whether daily administration of pyrantel tartrate can prevent infection in horses experimentally challenged with Sarcocystis neurona.

Animals—24 mixed-breed specific-pathogen-free weanling horses, 10 adult horses, 1 opossum, and 6 mice.

ProcedureSarcocystis neurona-naïve weanling horses were randomly allocated to 2 groups. Group A received pyrantel tartrate at the labeled dose, and group B received a nonmedicated pellet. Both groups were orally inoculated with 100 sporocysts/d for 28 days, 500 sporocysts/d for 28 days, and 1,000 sporocysts/ d for 56 days. Blood samples were collected weekly, and CSF was collected monthly. Ten seronegative adult horses were monitored as untreated, uninfected control animals. All serum and CSF samples were tested by use of western blot tests to detect antibodies against S neurona. At the end of the study, the number of seropositive and CSF-positive horses in groups A and B were compared by use of the Fisher exact test. Time to seroconversion on the basis of treatment groups and sex of horses was compared in 2 univariable Cox proportional hazards models.

Results—After 134 days of sporocyst inoculation, no significant differences were found between groups A and B for results of western blot tests of serum or CSF. There were no significant differences in number of days to seroconversion on the basis of treatment groups or sex of horses. The control horses remained seronegative.

Conclusions and Clinical Relevance—Daily administration of pyrantel tartrate at the current labeled dose does not prevent S neurona infection in horses. (Am J Vet Res 2005;66:846–852)

Full access
in American Journal of Veterinary Research

Abstract

Objective—To describe antimicrobial susceptibility patterns in Campylobacter spp isolated from dairy cattle and farms managed organically and conventionally in the midwestern and northeastern United States.

Design—Longitudinal study.

Sample Population—128 farms.

Procedure—Samples and data were collected every 2 months from August 2000 to October 2001. Fecal samples were collected from calves and cows. Milk samples were obtained from the bulk tank and milk line filters. Environmental samples were obtained from a water source, feed bunks of lactating cows, and cattle housing areas. Campylobacter identification and antimicrobial susceptibility testing were performed at a central laboratory by use of microbroth dilution with 2 customized antimicrobial susceptibility panels.

Results—460 and 1,570 Campylobacter isolates were obtained from organic and conventional dairy farms, respectively. Most isolates from both farm types were susceptible to most antimicrobial agents tested, and antimicrobial susceptibility of conventional dairy isolates was decreased, compared with organic dairy isolates. Low proportions of isolates resistant to ampicillin (< 10%) and moderate proportions resistant (30% to 60%) to kanamycin, sulfamethoxazole, and tetracycline were observed on both farm types. The proportion of isolates resistant to tetracycline was higher for conventional than organic farms.

Conclusions and Clinical RelevanceCampylobacter isolates from dairy cattle and farms managed organically and conventionally had similar patterns of antimicrobial resistance; the proportion of resistant isolates was higher for conventional than organic farms.

Restricted access
in Journal of the American Veterinary Medical Association