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1.
Am J Vet Res ; 78(1): 57-62, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28029286

RESUMO

OBJECTIVE To determine the survivability of Mycobacterium bovis on salt and salt-mineral blocks in typical weather conditions in Michigan over two 12-day periods at the height of summer and winter. SAMPLE 4 salt (NaCl) and 4 salt-mineral blocks inoculated with pure cultures of a strain of M bovis currently circulating in Michigan livestock and wildlife. PROCEDURES In the summer and again in the winter, inoculated blocks were placed in secured outdoor facilities where equal numbers of each block type (2/type/season) were exposed to shade or sunlight. Samples were collected from randomly selected areas on the surface of each block beginning within 1 hour after placement (day 0) twice a day for the first 4 days and once a day from days 7 through 11. Bacterial culture of samples was performed to detect viable M bovis. RESULTS Depending on the exposure conditions, salt blocks yielded viable M bovis for up to 2 days after inoculation and salt-mineral blocks yielded viable M bovis for > 3 days. Survival time was greatest on salt-mineral blocks kept outdoors in the shade during the winter. The odds of recovering viable M bovis from salt-mineral block samples were 4.9 times as great during the winter (vs the summer) and 3.0 times as great with exposure to shade (vs sunlight). CONCLUSIONS AND CLINICAL RELEVANCE Results from this study indicated that salt and salt-mineral blocks should be considered potential sources of bovine tuberculosis when designing risk mitigation programs for cattle herds in areas with wildlife reservoirs of M bovis.


Assuntos
Ração Animal , Microbiologia de Alimentos , Mycobacterium bovis/patogenicidade , Cloreto de Sódio , Tuberculose Bovina/microbiologia , Animais , Animais Selvagens , Bovinos , Reservatórios de Doenças , Michigan , Estações do Ano , Tuberculose Bovina/transmissão
2.
Foodborne Pathog Dis ; 13(4): 182-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26977814

RESUMO

Salmonella enterica (nontyphoidal) is one of the major causes of foodborne diseases in the United States and worldwide. Molecular typing methods are significant tools used to better understand the transmission and ecology of Salmonella in order to implement pre-harvest control measures. The objectives of this study were to describe the Salmonella genotypes, the distribution of isolate subtypes from different ecological niches (i.e., barn environment, nursery, and individual pigs) and their evolution over time in a longitudinal study conducted in three finishing sites (housing pigs from 10 weeks of age until slaughter at 24-26 weeks of age). Among the 107 Salmonella isolates submitted for pulsed-field gel electrophoresis (PFGE) analysis, there were 25 distinct subtypes. PFGE genotyping results were consistent with the serotype findings. A large number of distinguishable PFGE patterns (i.e., within the same serovar) were observed and different combinations of subtypes were identified within and across sites and cohorts. New subtypes may result of the introduction of new strains, genetic changes, or ongoing transmission of evolved strains within the production system. The same subtypes were detected intermittently during the study period, which suggests the persistence of indistinguishable subtypes in this production system. In addition, this study suggests persistence of the same subtype over several cohorts of pigs and potential residual contamination from the barn. Factors affecting adaptation and transmission of Salmonella within and among ecological systems (e.g., finishing pigs, nursery, and environment) should be further investigated. Understanding genotypic diversity of Salmonella in different ecological niches during pre-harvest may contribute to the development of more targeted and cost effective control programs during nursery and finishing phases.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Fenômenos Fisiológicos Bacterianos , Genes Bacterianos , Variação Genética , Salmonelose Animal/microbiologia , Salmonella/genética , Doenças dos Suínos/microbiologia , Criação de Animais Domésticos , Animais , Animais Recém-Nascidos , Eletroforese em Gel de Campo Pulsado/veterinária , Microbiologia Ambiental , Fezes/microbiologia , Técnicas de Genotipagem/veterinária , Meio-Oeste dos Estados Unidos , Tipagem Molecular/veterinária , Salmonella/classificação , Salmonella/crescimento & desenvolvimento , Salmonella/isolamento & purificação , Salmonelose Animal/diagnóstico , Sorotipagem/veterinária , Análise Espaço-Temporal , Sus scrofa , Suínos , Doenças dos Suínos/diagnóstico
3.
Appl Environ Microbiol ; 81(17): 5724-35, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26070676

RESUMO

Temporal changes in the distribution of Salmonella subtypes in livestock populations may have important impacts on human health. The first objective of this research was to determine the within-farm changes in the population of subtypes of Salmonella on Michigan dairy farms that were sampled longitudinally in 2000-2001 and again in 2009. The second objective was to determine the yearly frequency (2001 through 2012) of reported human illnesses in Michigan associated with the same subtypes. Comparable sampling techniques were used to collect fecal and environmental samples from the same 18 Michigan dairy farms in 2000-2001 and 2009. Serotypes, multilocus sequence types (STs), and pulsed-field gel electrophoresis (PFGE) banding patterns were identified for isolates from 6 farms where >1 Salmonella isolate was recovered in both 2000-2001 and 2009. The distribution of STs was significantly different between time frames (P < 0.05); only two of 31 PFGE patterns were identified in both time frames, and each was recovered from the same farm in each time frame. Previously reported within-farm decreases in the frequency of multidrug-resistant (MDR) Salmonella were due to recovery of MDR subtypes of S. enterica serotypes Senftenberg and Typhimurium in 2000-2001 and genetically distinct, pansusceptible subtypes of the same serotypes in 2009. The annual frequency of human illnesses between 2001 and 2012 with a PFGE pattern matching a bovine strain decreased for patterns recovered from dairy farms in 2000-2001 and increased for patterns recovered in 2009. These data suggest important changes in the population of Salmonella on dairy farms and in the frequency of human illnesses associated with cattle-derived subtypes.


Assuntos
Doenças dos Bovinos/microbiologia , Salmonelose Animal/microbiologia , Infecções por Salmonella/microbiologia , Salmonella/isolamento & purificação , Animais , Antibacterianos/farmacologia , Bovinos , Humanos , Michigan , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Filogenia , Salmonella/classificação , Salmonella/efeitos dos fármacos , Salmonella/genética , Sorotipagem
4.
Appl Environ Microbiol ; 79(20): 6501-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23956383

RESUMO

The purpose of this study was to compare the performance of a molecular detection technique (nested PCR) with that of mycobacterial culture in the detection of Mycobacterium bovis DNA in a set of 687 samples of experimentally inoculated environmental substrates (hay, soil, corn, water) exposed to natural weather conditions in Michigan. Four replicates of each substrate were used; half were autoclaved for sterilization, all were inoculated with 50,000 CFU of M. bovis isolated from Michigan livestock, and all were placed in outdoor enclosures, with half under shade and the other half exposed to direct sunlight. Samples were tested for the presence of M. bovis during one 12-month period, with monthly sample testing and during three 12-week periods (winter, spring, summer) with weekly sample testing. Samples were subjected to mycobacterial culture for isolation of M. bovis and a nested PCR with two primer sets targeting IS6110 to detect M. bovis DNA. In 128 samples tested during the 12-month period, M. bovis was not detectable by culture after 2 months but M. bovis DNA was detectable by PCR for at least 7 months. Of the 559 samples tested during the 12-week periods, PCR detected M. bovis DNA for up to 88 days in all of the sample types. There were no significant differences in the detection of M. bovis between shade and sun samples or between sterile and unsterilized samples, regardless of the detection method (PCR or culture). For use in epidemiologic investigations, the PCR assay was more rapid than mycobacterial culture, was not hindered by contaminating organisms, and detected M. bovis DNA in environment samples much longer after initial contamination than mycobacterial culture did.


Assuntos
Técnicas Bacteriológicas/métodos , Microbiologia Ambiental , Mycobacterium bovis/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Michigan , Mycobacterium bovis/genética , Mycobacterium bovis/crescimento & desenvolvimento , Sensibilidade e Especificidade , Fatores de Tempo
5.
Emerg Infect Dis ; 18(11): 1763-70, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23092744

RESUMO

We report an outbreak of severe respiratory disease associated with a novel Mycoplasma species in ferrets. During 2009-2012, a respiratory disease characterized by nonproductive coughing affected ≈8,000 ferrets, 6-8 weeks of age, which had been imported from a breeding facility in Canada. Almost 95% became ill, but almost none died. Treatments temporarily decreased all clinical signs except cough. Postmortem examinations of euthanized ferrets revealed bronchointerstitial pneumonia with prominent hyperplasia of bronchiole-associated lymphoid tissue. Immunohistochemical analysis with polyclonal antibody against Mycoplasma bovis demonstrated intense staining along the bronchiolar brush border. Bronchoalveolar lavage samples from 12 affected ferrets yielded fast-growing, glucose-fermenting mycoplasmas. Nucleic acid sequence analysis of PCR-derived amplicons from portions of the 16S rDNA and RNA polymerase B genes failed to identify the mycoplasmas but showed that they were most similar to M. molare and M. lagogenitalium. These findings indicate a causal association between the novel Mycoplasma species and the newly recognized pulmonary disease.


Assuntos
Furões/microbiologia , Infecções por Mycoplasma/veterinária , Mycoplasma/classificação , Animais , Canadá/epidemiologia , Surtos de Doenças , Feminino , Genes Bacterianos , Pulmão/microbiologia , Pulmão/patologia , Pulmão/ultraestrutura , Mycoplasma/genética , Mycoplasma/ultraestrutura , Infecções por Mycoplasma/diagnóstico , Infecções por Mycoplasma/epidemiologia , Filogenia , RNA Ribossômico 16S , Estados Unidos/epidemiologia
6.
J Feline Med Surg ; 14(10): 729-40, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22710859

RESUMO

The clinical and diagnostic features of 155 cats with urinary tract infection (UTI) and 186 controls with negative urine culture/s were characterized retrospectively (signalment, clinical signs, urinalysis, urine culture, concurrent diseases, lower urinary tract diagnostic/therapeutic procedures). Multivariable logistic regression was used to identify risk factors associated with UTI. Cats of all ages were affected by UTI with no sex/breed predisposition. Lower urinary tract signs were absent in 35.5% of cats with UTI. Pyuria and bacteriuria had sensitivities of 52.9% and 72.9%, and specificities of 85.5% and 67.7% for detection of UTI, respectively. Risk factors significantly associated with increased odds of UTI were urinary incontinence [odds ratio (OR)=10.78, P=0.0331], transurethral procedures (OR=8.37, P<0.0001), urogenital surgery (OR=6.03, P=0.0385), gastrointestinal disease (OR=2.62, P=0.0331), decreased body weight (OR=0.81, P=0.0259) and decreased urine specific gravity (OR=0.78, P=0.0055). Whilst not independently significant, renal disease and lower urinary tract anatomic abnormalities improved statistical model performance and contributed to UTI.


Assuntos
Doenças do Gato/diagnóstico , Doenças do Gato/epidemiologia , Infecções Urinárias/veterinária , Animais , Gatos , Feminino , Masculino , Análise de Regressão , Estudos Retrospectivos , Fatores de Risco , Incontinência Urinária/veterinária , Infecções Urinárias/diagnóstico , Infecções Urinárias/epidemiologia , Medicina Veterinária/métodos
7.
Vet Med Int ; 2011: 765430, 2011 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-21547222

RESUMO

Reisolation of Mycobacterium bovis from inoculated substrates was used to follow the persistence of viable M. bovis bacteria exposed to natural weather conditions over a 12-month period. Environmental factors were recorded continuously, and factors affecting M. bovis persistence (i.e., temperature, season, and substrate) were studied using survival analysis and Cox's proportional hazards regression. Persistence of M. bovis in the environment was significantly shorter in the spring/summer season, characterized by the highest average daily temperatures over the 12-month period. M. bovis persisted up to 88 days in soil, 58 days in water and hay, and 43 days on corn. These studies demonstrate that M. bovis bacteria persist long enough to represent a risk of exposure for cattle and/or wildlife and strengthen evidence that suggests cattle farm biosecurity and efforts to eliminate supplemental feeding of white-tailed deer will decrease the risk of bovine TB transmission among and between cattle and deer populations.

8.
J Vet Diagn Invest ; 23(2): 363-6, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21398465

RESUMO

In the United States, tuberculosis of captive cervids, caused by Mycobacterium bovis, attracted attention in 1991 when investigations, prompted by the identification of a tuberculous elk (Cervus elaphus nelsoni) of U.S. origin exported to Canada, revealed tuberculosis in 10 different elk herds in 8 different states. Based on methods used in cattle, official regulations pertaining to testing and eradication of tuberculosis in captive cervids were added to the U.S. Department of Agriculture bovine tuberculosis eradication effort in 1994. However, little published information exists on the accuracy of intradermal tuberculin testing in naturally infected cervids. Evaluation of a captive herd of 71 animals in Wisconsin included postmortem examination and tissue sample collection from both tuberculin test responders and nonresponders. Within this captive herd, of admittedly small size, results showed the single cervical test to have a sensitivity of 88% and a specificity of 69%. Evaluation of diagnostic tests in the species of interest is important, as extrapolation of data obtained from other species may not be appropriate.


Assuntos
Cervos/microbiologia , Mycobacterium bovis/isolamento & purificação , Teste Tuberculínico/veterinária , Tuberculose/veterinária , Animais , Teste Tuberculínico/normas , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Tuberculose/microbiologia , Wisconsin/epidemiologia
9.
Vet Ophthalmol ; 12(6): 343-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19883463

RESUMO

OBJECTIVE: To evaluate whether equine serum administered via a simulated subpalpebral lavage system (SPL) supports proliferation of Streptococcus zooepidemicus or Pseudomonas aeruginosa within the tubing. PROCEDURES: A sterile i.v. catheter with injection cap was inserted into sterilized silicone tubing (Mila). To mimic an SPL within the dorsal conjunctival fornix, the tubing was secured to an elevated platform. The tip of the tubing extended from the platform into a vial containing culture medium just inoculated with approximately 1.5 x 10(8) CFU/mL P. aeruginosa or S. zooepidemicus. To mimic administration of medication, the tubing was infused twice daily with equine serum, sterile saline (negative control), or culture medium (positive control) followed by air. Incubation was at 25 or 37 degrees C. At 24, 48, and 72 h postinoculation, samples were obtained for bacterial culture from one simulated SPL for each experimental variant. The following sections were cultured: (i) tubing tip previously submerged in the inoculated culture medium, (ii) tubing mid-section, and (iii) tip of the i.v. catheter. The experiment was performed in triplicate. RESULTS: Streptococcus zooepidemicus or P. aeruginosa were isolated from 100% of the tubing tips. Streptococcus zooepidemicus was isolated from one mid-section flushed with culture medium incubated at 37 degrees C. All other samples were negative for growth of the inoculated agents. CONCLUSIONS: Streptococcus zooepidemicus and P. aeruginosa did not proliferate within silicone tubing infused with equine serum. These data suggest that topical serum can be safely administered through a superiorly placed SPL in clinical cases.


Assuntos
Meios de Cultura/química , Cavalos , Pseudomonas aeruginosa , Soro , Streptococcus equi , Animais , Proliferação de Células , Modelos Biológicos , Soro/microbiologia
10.
J Clin Microbiol ; 47(12): 4109-12, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19846639

RESUMO

An intervention study was conducted to determine whether discontinuing the feeding of milk replacer medicated with oxytetracycline and neomycin to preweaned calves reduced antimicrobial resistance in Salmonella, Campylobacter, and Escherichia coli bacteria. Results demonstrated that the intervention did reduce multidrug resistance in these bacteria but that other factors also influenced multidrug resistance.


Assuntos
Ração Animal , Antibacterianos , Indústria de Laticínios , Farmacorresistência Bacteriana Múltipla , Fezes/microbiologia , Bactérias Gram-Negativas/efeitos dos fármacos , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Campylobacter/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Feminino , Bactérias Gram-Negativas/classificação , Testes de Sensibilidade Microbiana , Neomicina/química , Neomicina/farmacologia , Oxitetraciclina/química , Oxitetraciclina/farmacologia , Salmonella/efeitos dos fármacos
12.
Vet Surg ; 38(5): 664-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19573072

RESUMO

OBJECTIVE: To report the minimum inhibitory concentration (MIC) of amikacin sulfate for equine clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and characterize the initial kill and duration of the postantibiotic effect (PAE) for selected strains. STUDY DESIGN: Experimental study. METHODS: Isolates of MRSA (n=35) had their amikacin MIC determined using the E-test agar diffusion method. Two isolates with MICs>256 microg/mL limit were further characterized using broth macrodilution. Six distinct isolates with amikacin MICs of 32, 48, 128 (2 isolates) and 500 (2 isolates) microg/mL had PAE determinations made over a range of amikacin concentrations from 31.25-1000 microg/mL using standard culture-based techniques. RESULTS: Median MIC of the 35 isolates was 32 microg/mL (range 2 to >256 microg/mL). Mean PAE of selected MRSA strains had an overall mean (all amikacin doses) of 3.43 hours (range 0.10-9.57 hours). PAE for MRSA exposed to amikacin at 1000 microg/mL was 6.18 hours (range 3.30-9.57 hours), significantly longer than that for all other concentrations (P<.0001). There was no statistically significant effect of isolate MIC on PAE. CONCLUSIONS: Isolates had a wide range of MIC; however, growth of all 6 selected strains were inhibited within the range of concentrations tested, including 2 strains with MICs of 500 microg/mL. PAE duration was not influenced by the MIC of amikacin but was significantly longer with treatment at 1000 microg/mL than at lower concentrations. CLINICAL RELEVANCE: Clinical isolates of MRSA are susceptible to amikacin at concentrations achieved by regional perfusion: however, the modest duration of PAE observed suggest that further laboratory and in vivo evaluation be conducted before recommending the technique for clinical use.


Assuntos
Amicacina/farmacologia , Antibacterianos/farmacologia , Doenças dos Cavalos/microbiologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Infecções Estafilocócicas/microbiologia , Animais , Cavalos , Testes de Sensibilidade Microbiana
13.
J Clin Microbiol ; 46(6): 1968-77, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18417664

RESUMO

A randomized intervention study was conducted to determine if discontinuing use of calf milk replacer medicated with oxytetracycline results in increased tetracycline susceptibility in Salmonella and Campylobacter spp. and Escherichia coli in dairy calves over a 12-month period. Dairy herds with enteric bacteria with known low tetracycline susceptibility were enrolled for the study. Fecal samples from preweaned calves and environmental samples were collected from eight dairy herds in Michigan and New York State. Samples were collected monthly for 3 months prior to and 12 months after four of the eight herds discontinued medicated milk replacer feeding. Salmonella and Campylobacter spp. and E. coli were isolated, and antimicrobial susceptibility testing was conducted using automated broth microdilution. A total of 804 intervention and 1,026 control calf fecal samples and 122 intervention and 136 control environmental samples were collected for testing. No differences in owner-reported morbidity and mortality between treatment groups were seen. The intervention was significantly associated with increasing tetracycline susceptibility in E. coli and Salmonella. Tetracycline susceptibility increased in intervention herds for the first 3 months after switching to nonmedicated milk replacer but declined in subsequent months. Discontinuing the practice of feeding medicated milk replacers to calves increased tetracycline susceptibility in E. coli and Salmonella on dairy farms, without increasing cattle disease, but declines in effectiveness after 3 months suggest that other factors contribute to decreasing susceptibility on the farm.


Assuntos
Antibacterianos/farmacologia , Doenças dos Bovinos/microbiologia , Indústria de Laticínios , Diarreia/veterinária , Farmacorresistência Bacteriana , Tetraciclina/farmacologia , Criação de Animais Domésticos , Animais , Antibacterianos/administração & dosagem , Campylobacter/efeitos dos fármacos , Campylobacter/isolamento & purificação , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/mortalidade , Diarreia/epidemiologia , Diarreia/microbiologia , Diarreia/mortalidade , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Testes de Sensibilidade Microbiana , Leite/química , Neomicina/administração & dosagem , Oxitetraciclina/administração & dosagem , Salmonella/efeitos dos fármacos , Salmonella/isolamento & purificação , Desmame
14.
J Wildl Dis ; 43(3): 353-65, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17699074

RESUMO

Mycobacterium bovis has a wide host range that includes several wildlife species, and this can hamper attempts to eradicate bovine tuberculosis from livestock. The purpose of this study was to determine if common rodent species, namely meadow voles (Microtus pennsylvanicus), house mice (Mus musculus), and Norway rats (Rattus norvegicus), that inhabit the bovine tuberculosis endemic area of Michigan, can be experimentally infected with M. bovis. The objectives of the study were: 1) to determine if these rodent species can be infected, and if so, to document attendant pathologic processes/pathogenesis; 2) to detect any fecal shedding of M. bovis; and 3) to evaluate the relative susceptibility of the three species to M. bovis infection. For each species (n=36) there were two treatment (n=12/group) and one or two control groups depending on species (n=6-12/group); the maximum study duration was 60 days. The meadow vole treatments consisted of high dose inocula that were given by oral or intranasal routes, whereas the house mice and Norway rats were given only oral inocula at either a high or low dose. Of the three species, meadow voles were most susceptible to M. bovis infection. Upon intranasal inoculation, all 12 voles were infected as determined by gross and microscopic lesions and culture of M. bovis from tissue and feces. Seven of the 12 meadow voles inoculated orally were infected. House mice also were susceptible; M. bovis was isolated from 14 of 24 animals. Only one Norway rat in the high dose treatment group was positive by culture and this was the only animal from which minimal attendant lesions were observed. Results of this study indicate that meadow voles and house mice can be infected with M. bovis and might serve as spillover hosts. Concerted efforts should, therefore, be made to reduce or eliminate these rodents on premises where M. bovis-infected livestock are present.


Assuntos
Arvicolinae/microbiologia , Mycobacterium bovis/patogenicidade , Doenças dos Roedores/microbiologia , Doenças dos Roedores/transmissão , Tuberculose/veterinária , Administração Intranasal , Administração Oral , Animais , Animais Selvagens/microbiologia , Contagem de Colônia Microbiana , Reservatórios de Doenças/microbiologia , Reservatórios de Doenças/veterinária , Suscetibilidade a Doenças , Fezes/microbiologia , Feminino , Masculino , Camundongos , Michigan , Mycobacterium bovis/isolamento & purificação , Distribuição Aleatória , Ratos , Doenças dos Roedores/patologia , Especificidade da Espécie , Tuberculose/microbiologia , Tuberculose/patologia , Tuberculose/transmissão
15.
J Am Vet Med Assoc ; 230(11): 1657-64, 2007 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-17542733

RESUMO

OBJECTIVE: To determine the prevalence of antibodies against 6 Leptospira serovars and determine risk factors associated with positive Leptospira titers in healthy client-owned dogs in Michigan. DESIGN: Cross-sectional study. ANIMALS: 1,241 healthy dogs at least 4 months of age. PROCEDURES: Dogs were examined by veterinarians at private practices. Vaccinated and unvaccinated dogs were enrolled in the study, which occurred prior to the availability of a 4-serovar (Canicola, Grippotyphosa, Icterohaemorrhagiae, and Pomona) Leptospira vaccine. Sera were tested by use of the microscopic agglutination test to determine antibody titers against Leptospira serovars Bratislava, Canicola, Grippotyphosa, Hardjo, Icterohaemorrhagiae, and Pomona. A questionnaire was used to collect demographic information about each dog to identify risk factors associated with seropositive status. RESULTS: 309 of 1,241 (24.9%) dogs had antibody titers against at least 1 of the 6 Leptospira serovars, which suggested exposure to Leptospira spp. Prevalence of antibodies was highest to serovar Grippotyphosa, followed by Bratislava, Canicola, Icterohaemorrhagiae, and Pomona. Age, travel outside Michigan, exercise outside fenced yards, and exposure to livestock and wildlife were significant risk factors for positive titers. CONCLUSIONS AND CLINICAL RELEVANCE: Among healthy dogs from the lower peninsula of Michigan, > 20% have antibodies against leptospiral serovars historically considered uncommon but more recently incriminated as causing clinical canine leptospirosis. Wildlife and livestock may be of increasing importance as reservoirs for canine leptospirosis as urbanization continues to occur. Expanded vaccination strategies may partially mitigate these trends.


Assuntos
Anticorpos Antibacterianos/sangue , Vacinas Bacterianas/imunologia , Doenças do Cão/epidemiologia , Leptospira/imunologia , Leptospirose/veterinária , Testes de Aglutinação/veterinária , Animais , Animais Selvagens , Estudos Transversais , Doenças do Cão/microbiologia , Doenças do Cão/prevenção & controle , Cães , Feminino , Leptospira/classificação , Leptospirose/epidemiologia , Leptospirose/microbiologia , Leptospirose/prevenção & controle , Masculino , Michigan/epidemiologia , Filogenia , Fatores de Risco , Estudos Soroepidemiológicos , Viagem
16.
Am J Vet Res ; 66(10): 1816-22, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16273916

RESUMO

OBJECTIVE: To evaluate gross, histopathologic, and serum biochemical findings caused by Leptospira interrogans serovars pomona and bratislava inoculated in dogs. ANIMALS: Twenty-seven 8-week-old female Beagles. PROCEDURE: Dogs were randomly assigned to challenge or control groups. Challenge groups were conjunctivally inoculated on 3 successive days with 5 x 10(7) L interrogans serovar pomona (n = 12) or serovar bratislava (11). Clinical signs were recorded throughout the experiment, and clinical pathology assays, bacteriologic culture, and necropsies (6 or 7 dogs necropsied at each time point) were done on postinoculation day (PID) 7, 10, 14, and 20. RESULTS: Infection could not be confirmed in any serovar bratislava-inoculated dog, and control dogs remained healthy throughout the experiment. Positive culture and fluorescent antibody test results were confirmed in 11 of 12 serovar pomona-inoculated dogs. Fever and lethargy starting at PID 7 were the most common clinical signs in serovar pomona-infected dogs. On day 10, gross lesions included multifocal renal and pulmonary hemorrhage and perirenal edema. Serovar pomona-inoculated dogs had histopathologic lesions including hepatitis, interstitial nephritis, and pneumonia at PID 7, 10, 14, and 20. Increases in BUN, anion gap, and bilirubin concentration occurred on PID 10, 14, and 20. Platelet counts in dogs with positive results of bacteriologic culture were decreased from baseline values on PID 10, 12, and 14. CONCLUSIONS AND CLINICAL RELEVANCE: Conjunctival inoculation with L interrogans serovar pomona resulted in a high rate of infection with concomitant hemorrhagic and inflammatory lesions of the kidneys, liver, and lungs.


Assuntos
Doenças do Cão/microbiologia , Doenças do Cão/patologia , Leptospira interrogans serovar pomona , Leptospirose/veterinária , Animais , Análise Química do Sangue , Doenças do Cão/sangue , Cães , Imunofluorescência , Imuno-Histoquímica , Rim/patologia , Leptospirose/sangue , Leptospirose/patologia , Fígado/patologia , Pulmão/patologia , Reação em Cadeia da Polimerase , Testes Sorológicos , Especificidade da Espécie , Fatores de Tempo
18.
J Am Vet Med Assoc ; 226(3): 429-35, 2005 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-15702695

RESUMO

OBJECTIVE: To determine whether cattle testing positive for Mycobacterium avium subsp paratuberculosis as determined by microbial culture of feces or antibody ELISA were more likely to have false-positive responses on the caudal fold tuberculin (CFT) test or interferon-gamma (IFN-gamma) assay for Mycobacterium bovis than cattle testing negative for M paratuberculosis. ANIMALS: 1043 cattle from 10 herds in Michigan. PROCEDURE: Feces and blood samples for plasma were collected from cattle > or =24 months old on the day the CFT test was read. Fecal samples were submitted for microbial culture for M paratuberculosis. Plasma samples were tested for antibody against M paratuberculosis, and IFN-gamma after stimulation with purified protein derivative tuberculin from M bovis or M avium. RESULTS: Of 1043 cattle, 180 (17.3%) had positive CFT test results (suspects) and 8 (0.8%) had positive IFN-gamma assay results after stimulation with purified protein derivative tuberculin from M bovis. Forty-five (4.3%) and 115 (11.0%) cattle tested positive for M paratuberculosis as determined by microbial culture of feces and antibody ELISA, respectively. Cattle with positive responses for M paratuberculosis appeared to have an increased likelihood of false-positive results on the CFT test, although this association was not significant. CONCLUSIONS AND CLINICAL RELEVANCE: No significant association was detected among cattle testing positive for M paratuberculosis as determined by microbial culture of feces and antibody ELISA and positive CFT test and IFN-gamma assay results for M bovis.


Assuntos
Anticorpos Antibacterianos/sangue , Doenças dos Bovinos/diagnóstico , Interferon gama/sangue , Paratuberculose/diagnóstico , Tuberculose Bovina/diagnóstico , Animais , Bovinos , Doenças dos Bovinos/imunologia , Contagem de Colônia Microbiana/veterinária , Reações Cruzadas , Diagnóstico Diferencial , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/veterinária , Reações Falso-Positivas , Fezes/microbiologia , Mycobacterium avium subsp. paratuberculosis/imunologia , Mycobacterium bovis/imunologia , Paratuberculose/imunologia , Sensibilidade e Especificidade , Teste Tuberculínico/métodos , Teste Tuberculínico/veterinária , Tuberculose Bovina/imunologia
19.
Am J Vet Res ; 65(8): 1100-7, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15334844

RESUMO

OBJECTIVE: To develop a method for inducing acute leptospirosis in dogs. ANIMALS: 31 nine-week-old female Beagles. PROCEDURE: Beagles were randomly assigned to 2 inoculation groups or a control group. Dogs were inoculated on 3 successive days by conjunctival instillation of 5 x 10(7) cells of Leptospira kirschneri serovar grippotyphosa strain 82 (12 dogs) or strain RM 52 (14 dogs). Control dogs (n = 5) were similarly inoculated with sterile leptospiral culture media. Clinical signs, clinicopathologic variables, anti-leptospiral antibody titers, and evidence of leptospires in tissues and body fluids were evaluated. Dogs were euthanatized and necropsied on days 7, 14, 22, or 28 after inoculation or as required because of severe illness. RESULTS: Clinical signs in infected dogs included conjunctivitis, lethargy, diarrhea, dehydration, vomiting, and icterus. Consistent clinicopathologic alterations included azotemia, hyperphosphatemia, increased anion gap, hyperbilirubinemia, and an increase in alkaline phosphatase activity. Leptospires were cultured from the kidneys (11/12), urine (6/9), aqueous humor (9/12), blood (12/12), and liver (12/12) of dogs inoculated with strain 82. Only 3 of 14 dogs became infected after inoculation with strain RM 52. Histopathologic lesions in infected dogs included interstitial nephritis, renal tubular degeneration and necrosis, pulmonary hemorrhage, and hepatic edema and perivasculitis. CONCLUSIONS AND CLINICAL RELEVANCE: Conjunctival exposure to L kirschneri serovar grippotyphosa strain 82 resulted in acute leptospirosis in all inoculated dogs, but only 3 of 14 dogs inoculated with strain RM 52 became infected. This method of infection by serovar grippotyphosa can be used to study the pathogenesis and prevention of leptospirosis in dogs.


Assuntos
Anticorpos Antibacterianos/sangue , Doenças do Cão/microbiologia , Doenças do Cão/patologia , Leptospira , Leptospirose/veterinária , Animais , Análise Química do Sangue , Doenças do Cão/imunologia , Cães , Feminino , Imunofluorescência , Imuno-Histoquímica , Rim/microbiologia , Rim/patologia , Leptospirose/imunologia , Leptospirose/patologia , Fígado/microbiologia , Fígado/patologia , Pulmão/microbiologia , Pulmão/patologia , Especificidade da Espécie
20.
Avian Dis ; 48(2): 437-41, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15283434

RESUMO

Avian mycobacteriosis is an important disease in companion, captive, exotic, and wild birds worldwide. Mycobacterium avium is the most widely distributed and pathogenic organism causing tuberculous lesions in birds. Multiple factors including age, stress, immune status, and preexisting disease determine the pathogenicity of M. avium, and the disease can manifest itself in a variety of forms. Mycobacteriosis can cause severe losses in zoo aviaries, including the loss of rare and endangered bird species. We report a case of systemic avian mycobacteriosis in an adult, free-living male American bald eagle (Haliaeetus leucocephalus) that presented to the Diagnostic Center for Population and Animal Health in November 2003.


Assuntos
Doenças das Aves/microbiologia , Águias/microbiologia , Mycobacterium avium/isolamento & purificação , Tuberculose Aviária/microbiologia , Animais , Masculino
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