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1.
PLoS One ; 15(10): e0240479, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33057397

RESUMO

Strangles is a common disease of horses with worldwide distribution caused by the bacterium Streptococcus equi subspecies equi (SEE). Although vaccines against strangles are available commercially, these products have limitations in safety and efficacy. The microbial surface antigen ß 1→6 poly-N-acetylglucosamine (PNAG) is expressed by SEE. Here we show that intramuscular (IM) injection alone or a combination of IM plus intranasal (IN) immunization generated antibodies to PNAG that functioned to deposit complement and mediate opsonophagocytic killing of SEE ex vivo. However, immunization strategies targeting PNAG either by either IM only injection or a combination of IM and IN immunizations failed to protect yearling horses against infection following contact with infected horses in an experimental setting. We speculate that a protective vaccine against strangles will require additional components, such as those targeting SEE enzymes that degrade or inactivate equine IgG.


Assuntos
Acetilglucosamina/imunologia , Anticorpos Antibacterianos/imunologia , Doenças dos Cavalos/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus equi/imunologia , Vacinação/veterinária , Animais , Feminino , Doenças dos Cavalos/imunologia , Cavalos , Imunização , Injeções Intramusculares , Masculino , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/microbiologia
2.
Appl Environ Microbiol ; 86(22)2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-32887718

RESUMO

Salmonella enterica subsp. enterica serovar Abortusequi is a frequently reported pathogen causing abortion in mares. In this study, the preventive and therapeutic effects of phage PIZ SAE-01E2 against S Abortusequi in a mouse model of abortion were investigated. Phage PIZ SAE-01E2 was stable at different temperatures (4 to 70°C) and pH values (pH 4 to 10) and could lyse the majority of the Salmonella serogroup O:4 and O:9 strains tested (25/28). There was no lysogeny-related, toxin, or antibiotic resistance-related gene in the genome of PIZ SAE-01E2. All of these characteristics indicate that PIZ SAE-01E2 has the potential for use in phage therapy. In in vivo experiments, 2 × 103 CFU/mouse of S Abortusequi ATCC 9842 was sufficient to lead to murine abortion (gestational day 14.5) within 48 h. A single intraperitoneal inoculation of PIZ SAE-01E2 (108 PFU/mouse, multiplicity of infection = 105) 1 h before or after S Abortusequi challenge provided effective protection to all pregnant mice (10/10). After 24 h of treatment with phage PIZ SAE-01E2, the bacterial loads in both the placenta and the uterus of the infected mice were significantly decreased (<102 CFU/g) compared to those in the placenta and the uterus of the mice in the control group (>106 CFU/g). In addition, the levels of inflammatory cytokines in the placenta and blood of the mice in the phage administration groups were significantly reduced (P < 0.05) compared to those in the placenta and blood of the mice in the control group. Altogether, these findings indicate that PIZ SAE-01E2 shows the potential to block abortions induced by S Abortusequi in vivo IMPORTANCE S Abortusequi is an important pathogen that can induce abortions in mares. Although S Abortusequi has been well controlled in Europe and the United States due to strict breeding and health policies, it is still widespread in African and Asian countries and has proven difficult to control. In China, abortions caused by S Abortusequi have also been reported in donkeys. So far, there is no commercial vaccine. Thus, exploiting alternative efficient and safe strategies to control S Abortusequi infection is essential. In this study, a new lytic phage, PIZ SAE-01E2, infecting S Abortusequi was isolated, and the characteristics of PIZ SAE-01E2 indicated that it has the potential for use in phage therapy. A single intraperitoneal inoculation of PIZ SAE-01E2 before or after S Abortusequi challenge provided effective protection to all pregnant mice. Thus, PIZ SAE-01E2 showed the potential to block abortions induced by S Abortusequi in vivo.


Assuntos
Aborto Animal/prevenção & controle , Bacteriófagos/fisiologia , Doenças dos Cavalos/prevenção & controle , Salmonelose Animal/prevenção & controle , Salmonella/fisiologia , Aborto Animal/microbiologia , Aborto Animal/virologia , Animais , Feminino , Doenças dos Cavalos/microbiologia , Doenças dos Cavalos/virologia , Cavalos , Camundongos , Camundongos Endogâmicos ICR , Gravidez , Salmonelose Animal/microbiologia , Salmonelose Animal/virologia
3.
Vet Surg ; 49(7): 1283-1291, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32767594

RESUMO

OBJECTIVE: To describe the prevalence and antimicrobial susceptibility of bacterial isolates cultured from surgical specimens of infected arytenoid cartilage and granulomas. STUDY DESIGN: Retrospective cohort study. ANIMALS: Thirty-three thoroughbred horses. METHODS: Hospital records were retrieved for all horses admitted to a referral hospital for arytenoid chondropathy surgery that had samples submitted for culture and sensitivity between 2005 and 2019. Descriptive analyses were performed. RESULTS: In total, 56 bacterial isolates were obtained. Gram-positive bacteria (58%), Gram-negative bacteria (54%), and anaerobes (33%) were cultured from samples. Fifty-eight percent of horses had multiple bacteria isolated. Streptococcus spp were the most common (32%), followed by Enterobacteriaceae (13%). Bacterial isolates were sensitive to ceftiofur (83%), followed by ampicillin (64%), tetracycline (48%), enrofloxacin (45%), trimethoprim-sulfamethoxazole (41%), and gentamicin (18%). Multidrug resistance (MDR) was present in 44% of bacterial isolates. CONCLUSION: A wide variety of bacteria was cultured, providing evidence that secondary opportunistic infection by common respiratory bacteria is likely a factor in arytenoid chondropathy. Multidrug resistance was higher than what has been previously reported in equine respiratory samples. Trimethoprim-sulfamethoxazole had low effectiveness. CLINICAL SIGNIFICANCE: Because culture and sensitivity testing is not available in the diagnosis of mild to moderate arytenoid chondropathy, the information from this study may allow for more targeted broad-spectrum antimicrobial treatment to limit disease progression when the disease is first identified. The antimicrobial susceptibilities and MDR found in this study emphasize the importance of following current antimicrobial guidelines and highlight the requirement for surgical intervention rather than continued medical treatment in cases that do not resolve with initial antimicrobial therapy.


Assuntos
Antibacterianos/farmacologia , Cartilagem Aritenoide/patologia , Bactérias/efeitos dos fármacos , Doenças das Cartilagens/veterinária , Farmacorresistência Bacteriana , Doenças dos Cavalos/microbiologia , Animais , Doenças das Cartilagens/tratamento farmacológico , Doenças das Cartilagens/microbiologia , Bactérias Gram-Negativas , Doenças dos Cavalos/tratamento farmacológico , Cavalos , Testes de Sensibilidade Microbiana/veterinária , Estudos Retrospectivos
4.
J Vet Sci ; 21(4): e54, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32735092

RESUMO

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of severe infections in humans and animals worldwide. Studies elucidating the population structure, staphylococcal cassette chromosome mec types, resistance phenotypes, and virulence gene profiles of animal-associated MRSA are needed to understand spread and transmission. OBJECTIVES: The objective of this study was to determine 1) clonal complexes and spa types, 2) resistance phenotypes, and 3) virulence/resistance gene profiles of MRSA isolated from animals in Switzerland. METHODS: We analyzed 31 presumptive MRSA isolates collected from clinical infections in horses, dogs, cattle, sheep, and pigs, which had tested positive in the Staphaurex Latex Agglutination Test. The isolates were characterized by spa typing and DNA microarray profiling. In addition, we performed antimicrobial susceptibility testing using the VITEK 2 Compact system. RESULTS: Characterization of the 31 presumptive MRSA isolates revealed 3 methicillin-resistant Staphylococcus pseudintermedius isolates, which were able to grow on MRSA2 Brilliance agar. Of the 28 MRSA isolates, the majority was assigned to CC398 (86%), but CC8 (11%) and CC1 (4%) were also detected. The predominant spa type was t011 (n = 23), followed by t009 (n = 2), t034 (n = 1), t008 (n = 1), and t127 (n = 1). CONCLUSIONS: The results of this study extend the current body of knowledge on the population structure, resistance phenotypes, and virulence and resistance gene profiles of MRSA from livestock and companion animals.


Assuntos
Resistência Microbiana a Medicamentos/genética , Staphylococcus aureus Resistente à Meticilina/genética , Análise de Sequência com Séries de Oligonucleotídeos/veterinária , Infecções Estafilocócicas/veterinária , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Doenças do Cão/microbiologia , Cães , Doenças dos Cavalos/microbiologia , Cavalos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Fenótipo , Ovinos , Doenças dos Ovinos/microbiologia , Infecções Estafilocócicas/microbiologia , Suínos , Doenças dos Suínos/microbiologia
5.
J Vet Diagn Invest ; 32(5): 718-721, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32715980

RESUMO

Detection of Leptospira interrogans is difficult as a result of intermittent leptospiruria and brief leptospiremia. Hence, diagnosis relies heavily on serologic testing, the reference method of which is the microscopic agglutination test (MAT). In horses, clinical leptospirosis has been associated with abortion, recurrent uveitis, and sporadic cases of hepatic and renal disease. Little information exists on the seroprevalence of antibodies to L. interrogans in equids in the United States; past nationwide studies suggest that the seroprevalence in some areas is as high as 77% (reciprocal titer ≥ 100). We tested sera from 124 apparently healthy horses previously submitted for equine infectious anemia (EIA) serology using MAT for 6 serovars-Bratislava, Canicola, Grippotyphosa, Hardjo, Icterohaemorrhagiae, and Pomona. When using a reciprocal MAT titer cutoff of ≥ 100, 102 of 124 (82%) of the samples were positive for at least one serovar. Seropositivity was significantly associated with increasing age. Query of specimens from clinical cases submitted to the Colorado State University Veterinary Diagnostic Laboratory for MAT since 2010 indicated significantly greater seroprevalence (p = 0.015) of pathogenic serovar Pomona in clinical cases compared to sera submitted from healthy equids for routine EIA testing. Information from our diagnostic laboratory submission forms also suggests a correlation between uveitis or other ophthalmic problems and serovar Pomona.


Assuntos
Doenças dos Cavalos/epidemiologia , Leptospirose/veterinária , Fatores Etários , Animais , Anticorpos Antibacterianos/sangue , Colorado/epidemiologia , Feminino , Doenças dos Cavalos/microbiologia , Cavalos , Leptospira , Leptospirose/epidemiologia , Leptospirose/microbiologia , Masculino , Prevalência , Estudos Soroepidemiológicos , Sorogrupo
6.
J Vet Diagn Invest ; 32(4): 542-548, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32522107

RESUMO

Species of genus Chlamydia are important pathogens of animals, with a worldwide distribution and broad host range. Some species, such as Chlamydia psittaci, also pose a zoonotic disease risk. Abortion is one of the many diseases that has been associated with chlamydial infections in animals, with most attention focused on the economic impacts to sheep production. The role of chlamydia in equine abortions is unknown. Using the family-specific 23S ribosomal RNA (rRNA) Chlamydiaceae real-time PCR, we tested 169 formalin-fixed, paraffin-embedded fetal membrane samples from 162 equine abortion cases collected between 2000 and 2018 in Switzerland. Two equine abortion cases (1.2%) tested positive for Chlamydiaceae. Further analyses by the species-specific 23S rRNA ArrayMate microarray and sequencing of a fragment of the 16S rRNA gene revealed C. abortus and C. psittaci. In both cases, equine herpesvirus 1 was also present, which might have been the abortion cause, alone or in synergy with Chlamydia. The prevalence of abortigenic chlamydial species in equine abortion cases in our study was significantly lower than rates described elsewhere. Zoonotic chlamydial agents present in equine fetal membranes nevertheless should be considered a potential risk to humans during foaling, abortion, or stillbirth.


Assuntos
Aborto Animal/microbiologia , Infecções por Chlamydia/veterinária , Chlamydia/isolamento & purificação , Doenças dos Cavalos/epidemiologia , Animais , Infecções por Chlamydia/epidemiologia , Infecções por Chlamydia/microbiologia , Feminino , Doenças dos Cavalos/microbiologia , Cavalos , Imuno-Histoquímica/veterinária , Reação em Cadeia da Polimerase/veterinária , Prevalência , Estudos Retrospectivos , Suíça/epidemiologia
7.
Sci Rep ; 10(1): 7208, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32350359

RESUMO

This study aims to report the presence of Neorickettsia risticii DNA in blood samples from naturally infected horses in Rio de Janeiro, provide clinicopathological findings related to the infection, and report the phylogenetic diversity of the 16S rDNA of N. risticii in order to evaluate its heterogeneity. Real-time quantitative polymerase chain reaction (qPCR) was performed to investigate the presence of N. risticii in samples collected from horses (n = 187). Five positive samples were found in the molecular screening. Hypoalbuminemia and high levels of creatine kinase and lactate dehydrogenase were the predominant findings in the biochemical analysis. The sequences were similar to those of N. risticii. Phylogenetic analysis revealed genotype segregation based on the geographical distribution in the N. risticii sequence clade. Dendrograms constructed with five hypervariable regions revealed that V4 distinguished Neorickettsia at the species level and produced a phylogeny that best represented the phylogeny obtained with the complete 16S rDNA sequence. This is the first report of N. risticii DNA in the blood of Brazilian horses based on sequences deposited in GenBank. Further studies are necessary to clarify the epidemiological chain of this vector-borne parasite in order to determine and establish appropriate preventive measures in the equine trading market.


Assuntos
Infecções por Anaplasmataceae , DNA Bacteriano/genética , Doenças dos Cavalos , Cavalos , Neorickettsia risticii/genética , Filogenia , Infecções por Anaplasmataceae/diagnóstico , Infecções por Anaplasmataceae/genética , Infecções por Anaplasmataceae/microbiologia , Infecções por Anaplasmataceae/veterinária , Animais , Brasil , DNA Ribossômico/genética , Doenças dos Cavalos/diagnóstico , Doenças dos Cavalos/genética , Doenças dos Cavalos/microbiologia , Neorickettsia risticii/isolamento & purificação , RNA Bacteriano/genética , RNA Ribossômico 16S/genética
8.
Lab Chip ; 20(9): 1621-1627, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32334422

RESUMO

Rapid, sensitive and specific detection and reporting of infectious pathogens is important for patient management and epidemic surveillance. We demonstrated a point-of-care system integrated with a smartphone for detecting live virus from nasal swab media, using a panel of equine respiratory infectious diseases as a model system for corresponding human diseases such as COVID-19. Specific nucleic acid sequences of five pathogens were amplified by loop-mediated isothermal amplification on a microfluidic chip and detected at the end of reactions by the smartphone. Pathogen-spiked horse nasal swab samples were correctly diagnosed using our system, with a limit of detection comparable to that of the traditional lab-based test, polymerase chain reaction, with results achieved in ∼30 minutes.


Assuntos
Doenças dos Cavalos/diagnóstico , Dispositivos Lab-On-A-Chip , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Transtornos Respiratórios/veterinária , Smartphone , Animais , Betacoronavirus/isolamento & purificação , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Herpesvirus Equídeo 1/isolamento & purificação , Herpesvirus Equídeo 4/isolamento & purificação , Doenças dos Cavalos/microbiologia , Doenças dos Cavalos/virologia , Cavalos , Vírus da Influenza A Subtipo H3N8/isolamento & purificação , Aplicativos Móveis , Nariz/microbiologia , Nariz/virologia , Sistemas Automatizados de Assistência Junto ao Leito , Transtornos Respiratórios/diagnóstico , Transtornos Respiratórios/microbiologia , Transtornos Respiratórios/virologia , Streptococcus equi/isolamento & purificação
9.
Vet Microbiol ; 243: 108617, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32273003

RESUMO

Fourth-generation cephalosporins can select for extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae in horses, but it is unknown to what extent this occurs compared to penicillin/gentamicin combination treatment. The objective was to evaluate the effect of different antimicrobial treatments on faecal shedding and diversity of ESBL-producing Escherichia coli (ESBL-EC) in horses. Upon hospital admission, 86 horses in need of antimicrobial treatment or prophylaxis were randomly allocated to receive penicillin and gentamicin (PG) or cefquinome (CEF). Untreated horses were included as controls (NOAMD, n = 33). Faecal samples from admission (T1), 3 days after admission (T2), and faecal swabs 28 days after discharge (T3) were cultured selectively. Differences in prevalence (T1, T2, T3) and counts (T1, T2) of ESBL-EC between groups and over time were analysed. On a subset of ESBL-EC isolates, antimicrobial susceptibility testing (n = 45) and whole-genome sequencing followed by SNP-analysis (n = 46) were performed. The prevalence of ESBL-EC at T1 was 12 % with no significant difference between groups. In all groups, significantly higher carriage rates were observed at T2 and T3 compared to T1. Carriage and counts of ESBL-EC at T2 were significantly higher in treated compared to untreated horses. There was no significant difference between PG and CEF at any time points. Despite a large genetic diversity, indistinguishable ESBL clones were observed in different horses over time. In conclusion, antimicrobial treatment and hospitalization increased prevalence and counts of ESBL-EC, and transmission of ESBL-EC in the hospital was suspected. These findings highlight the importance of antimicrobial stewardship and infection control practices in equine medicine.


Assuntos
Antibacterianos/uso terapêutico , Derrame de Bactérias , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Fezes/microbiologia , Doenças dos Cavalos/tratamento farmacológico , Animais , Gestão de Antimicrobianos , Cefalosporinas/uso terapêutico , Escherichia coli/enzimologia , Feminino , Gentamicinas/uso terapêutico , Doenças dos Cavalos/microbiologia , Cavalos , Masculino , Penicilinas/uso terapêutico , Prevalência , beta-Lactamases
10.
Vet Microbiol ; 243: 108638, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32273017

RESUMO

Strangles, caused by Streptococcus equi subspecies equi (S. equi) is an infectious disease of horses with worldwide distribution, but there are limited data available regarding strain variation using whole genome sequencing among and within outbreaks in the United States (US), and how US isolates compare with S. equi isolated globally. To address this knowledge-gap, we compared the whole genomes of 54 S. equi isolates from Texas and Kentucky and those of 230 publicly available sequences of S. equi isolates collected from other countries. Our results show that despite minimal variation among isolates within an outbreak some mutations do occur among individual outbreak isolates. Some S. equi strains from the US are closely related to S. equi isolates from other countries, likely reflecting international dissemination of isolates. Collectively, these data improve our understanding of phenotypic and genotypic variation of isolates within an outbreak, and the international distribution of S. equi. We also identify a novel variant of the S. equi M-protein, and observed cases of strangles that were caused by the modified-live vaccine but that were not recognized as vaccine-associated at the time of clinical sample submission.


Assuntos
Surtos de Doenças/veterinária , Doenças dos Cavalos/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus/genética , Sequenciamento Completo do Genoma , Animais , Proteínas de Bactérias/genética , Variação Genética , Genótipo , Cavalos/microbiologia , Internacionalidade , Kentucky/epidemiologia , Mutação , Filogenia , Análise de Sequência de DNA , Texas/epidemiologia
11.
Int J Food Microbiol ; 325: 108627, 2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32334331

RESUMO

Fumonisins are mycotoxins that contaminate maize and maize-based food products, and feed. They have been associated with nerve system disorders in horses, pulmonary edema in swine as well as neural tube defects and esophageal cancer in humans. The fum1 gene codes for a polyketide synthase involved in the biosynthesis of fumonisins. It is present in the genomes of all fumonisin producing Fusarium spp. Reliable detection of fum1 can provide an estimate of the toxicological potential of cultures and food sources. Therefore, a fum1 specific LAMP assay was developed and tested with purified DNA of 48 different species from the Fusarium fujikuroi species complex (FFSC). The fum1 gene was detected in 22 species among which F. fujikuroi, F. globosum, F. nygamai, F. proliferatum, F. subglutinans and F. verticillioides were the most prominent fumonisin producers. None out of 92 tested non-Fusarium species showed cross reactions with the new assay. The lowest limit of detection (LOD) was 5 pg of genomic DNA per reaction for F. fujikuroi, F. nygamai and F. verticillioides. Higher LODs were found for other LAMP positive species. Apart from pure genomic DNA, the LAMP assay detected fumonisin-producers when 103 conidia/reaction were used as template after mechanical lysis. LAMP-results were well correlated with FB1 production. This is the first report on fumonisin production in strains of F. annanatum, F. coicis, F. mundagurra, F. newnesense, F. pininemorale, F. sororula, F. tjataeba, F. udum and F. werrikimbe. Usefulness of the LAMP assay was demonstrated by analyzing fumonisin contaminated maize grains. The new LAMP assay is rapid, sensitive and reliable for the diagnosis of typical fumonisin producers and can be a versatile tool in HACCP concepts that target the reduction of fumonisins in the food and feed chain.


Assuntos
Fumonisinas/metabolismo , Fusarium/genética , Técnicas de Diagnóstico Molecular/métodos , Micotoxinas/metabolismo , Técnicas de Amplificação de Ácido Nucleico/métodos , Policetídeo Sintases/genética , Animais , DNA Fúngico/genética , Fusarium/metabolismo , Doenças dos Cavalos/microbiologia , Cavalos , Humanos , Suínos , Doenças dos Suínos/microbiologia , Zea mays/microbiologia
12.
J Vet Intern Med ; 34(2): 996-1006, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32128892

RESUMO

BACKGROUND: Gastrointestinal microbiota can be influenced by several factors, including diet and systemic inflammation, and in turn could act as a modulator of the allergic response. Fecal microbiota of horses with asthma has not been described. HYPOTHESIS/OBJECTIVES: Analyze the bacterial fecal microbiota of horses with and without asthma under different environment and diet conditions, during both remission and exacerbation. METHODS: Prospective observational study. Feces from 6 asthmatic and 6 healthy horses were collected under 3 different conditions: on pasture, housed indoors receiving good quality hay ("good hay"), and housed indoors receiving poor quality hay ("dusty hay"). Sequencing was performed using an Illumina MiSeq platform and data were processed using the software mothur v.1.41.3 and LEfSe. RESULTS: In horses with asthma, low-abundance bacteria were more affected by changes in environment and diet (ie, when horses were experiencing an exacerbation), as shown by changes in membership and results from the LEfSe analysis. There was a significant increase in the relative abundance of Fibrobacter in healthy horses eating hay, a change that was not observed in horses with asthma. CONCLUSIONS AND CLINICAL IMPORTANCE: The intestinal microbiota of horses with asthma does not adapt in the same way to changes in diet and environment compared to the microbiota of healthy horses. Mechanisms explaining how airway obstruction and inflammation could influence the intestinal microbiota and how in turn this microbiota could modulate systemic inflammation in asthmatic horses deserves further investigation.


Assuntos
Asma/veterinária , Fezes/microbiologia , Doenças dos Cavalos/microbiologia , Animais , Asma/microbiologia , Líquido da Lavagem Broncoalveolar/citologia , Feminino , Cavalos , Masculino , Estudos Prospectivos
13.
Vet Rec ; 187(2): e14, 2020 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-32201380

RESUMO

BACKGROUND: Although Clostridioides difficile-associated diseases (CDAD) is considered to be associated with colitis in horses, few studies have been performed with a focus on the characteristics of CDAD in thoroughbred racehorses. METHODS: Between 2010 and 2018, a test for C. difficile was performed using faecal samples from 137 thoroughbred racehorses with colitis presenting with diarrhoea and fever. The mortality rate, clinical findings, predisposing factors and the selected treatments were investigated in a retrospective manner. RESULTS: Twenty-four cases were diagnosed as CDAD and 113 as non-CDAD. The mortality rate was significantly higher in the CDAD group (83 per cent) than that in the non-CDAD group (34 per cent). The levels of serum amyloid A, blood urea nitrogen and packed cell volume at initial presentation were also significantly higher, and those of total protein and albumin were significantly lower in the CDAD group. The development of CDAD was associated with the administration of antimicrobials, surgery and hospitalisation. No significant improvement in mortality was observed for any of the selected treatment in both groups. CONCLUSION: CDAD in thoroughbred racehorses was identified as a high mortality disease with rapid progression of systemic inflammation and deterioration of the circulatory state. Further investigation is required to improve the treatment.


Assuntos
/isolamento & purificação , Infecções por Clostridium/veterinária , Colite/veterinária , Doenças dos Cavalos/microbiologia , Animais , Causalidade , Infecções por Clostridium/microbiologia , Infecções por Clostridium/mortalidade , Infecções por Clostridium/terapia , Colite/microbiologia , Colite/mortalidade , Colite/terapia , Fezes/microbiologia , Feminino , Doenças dos Cavalos/mortalidade , Doenças dos Cavalos/terapia , Cavalos , Japão , Masculino , Estudos Retrospectivos
14.
Vet Microbiol ; 242: 108568, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32122582

RESUMO

Mainstay therapy for rhodococcosis in foals is the combination of rifampicin and a macrolide. While emergence of resistance to rifampicin and macrolides has been reported, studies demonstrating the development of resistance to such drugs is limited in necropsied foals with rhodococcosis. In this study, the foal necropsy records between 01/01/2011 and 08/30/2019 were reviewed for culture-positive R. equi with MICs and, whether or not the affected foals received any mainstay dual therapy before their deaths. Resistance to antimicrobials in the R. equi isolates from necropsied foals were then compared between treated foals with dual therapy and untreated foals to determine the association between the administration of antimicrobials and development of the drug resistance. In a total of 256 R. equi isolates from each of the 256 necropsied foals with rhodococcosis, rifampicin, azithromycin, clarithromycin and erythromycin showed high rates of resistance, 22.65 %, 16.01 %, 14.84 % and 15.23 %, respectively. The most active antimicrobials exhibiting MIC50/90 values were imipenem, doxycycline, amikacin and gentamicin including in the rifampicin- and macrolides-resistant R. equi isolates. Based on the treatment histories available for the 114 necropsied foals with rhodococcosis, R. equi isolates resistant to rifampicin, and macrolides were significantly more isolated from treated foals with mainstay dual therapy compared to untreated foals. Despite dual therapy, development of resistance against rifampicin and macrolides warrants evaluation of new treatment protocols in foals.


Assuntos
Infecções por Actinomycetales/veterinária , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Doenças dos Cavalos/microbiologia , Rhodococcus equi/efeitos dos fármacos , Infecções por Actinomycetales/tratamento farmacológico , Infecções por Actinomycetales/microbiologia , Animais , Azitromicina/farmacologia , Claritromicina/farmacologia , Eritromicina/farmacologia , Doenças dos Cavalos/tratamento farmacológico , Cavalos/microbiologia , Testes de Sensibilidade Microbiana
15.
Vet Microbiol ; 242: 108571, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32122585

RESUMO

BACKGROUND: Rhodococcus equi (R. equi) infections are endemic in many horse facilities in the United States resulting significant economic loses annually. Currently, there is no commercial vaccine available and the emergence of isolates that are resistant to the current treatment and prophylaxis using antibiotics prompts closer surveillance of this pathogen. OBJECTIVE: This study compares three different genotyping techniques, Pulsed Field Gel Electrophoresis (PFGE), Multilocus Sequence Typing (MLST) and whole genome SNP-based phylogeny to determine the most accurate method to monitor the spread of macrolide-and-rifampin-resistant R. equi. METHODS: 16 macrolide and rifampin-resistant and 6 susceptible R. equi and their Illumina Miseq whole genome sequences were used in this study. The isolates were sub-typed by PFGE with VspI and a dendrogram based on their similarities generated. Additionally, three phylogenetic trees were constructed using CSI phylogeny on (i) whole genome sequences (WGS), (ii) in silico MLST sequences and (iii) MLST sequences obtained after PCR-amplification and Sanger sequencing. RESULTS: PFGE identified 18 different genetic profiles and grouped the 22 isolates into 3 clusters independently of their susceptibilities. The phylogenetic trees built from WGS and MLST data showed similar topology, separating the isolates into 2 major clades in accordance with their susceptibility profiles (susceptible and resistant). However, only the trees generated with next generation sequencing data could detect the clonality of the resistant isolates.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Eletroforese em Gel de Campo Pulsado , Cavalos/microbiologia , Tipagem de Sequências Multilocus , Rhodococcus equi/efeitos dos fármacos , Sequenciamento Completo do Genoma , Infecções por Actinomycetales/microbiologia , Infecções por Actinomycetales/veterinária , Animais , Técnicas de Tipagem Bacteriana , Técnicas de Genotipagem , Doenças dos Cavalos/microbiologia , Macrolídeos/farmacologia , Testes de Sensibilidade Microbiana , Filogenia , Rhodococcus equi/classificação , Rifampina/farmacologia , Análise de Sequência de DNA
16.
J Vet Intern Med ; 34(2): 955-963, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32022351

RESUMO

BACKGROUND: Antimicrobial treatment protocols for foals with sepsis that do not improve clinically often are adjusted based on bacteriological and antimicrobial susceptibility testing results from samples collected at hospital admission. OBJECTIVES: To evaluate whether hospitalization for ≥48 hours affects bacteriological and antimicrobial susceptibility testing results. ANIMALS: Two-hundred sixty-seven foals <30 days of age admitted to a neonatal intensive care unit and diagnosed with sepsis. METHODS: Medical records were reviewed retrospectively to identify foals with sepsis and positive bacteriological cultures. Results from samples collected at hospital admission were compared to those collected ≥48 hours after admission. Logistic regression for clustered data and exact logistic regression were used for statistical analysis. RESULTS: Three-hundred fifty-three unique bacterial isolates were obtained from 231 foals at hospital admission and 92 unique bacterial isolates were obtained from 57 foals after ≥48 hours of hospitalization. Relative isolation frequency after ≥48 hours of hospitalization increased for Acinetobacter spp., 0.6% versus 3.3% (odds ratio [OR], 7.63; 95% confidence interval [CI], 1.28-45.45); Enterococcus spp., 4.8% versus 19.6% (OR, 5.37; 95% CI, 2.64-10.90); Klebsiella spp., 5.1% versus 10.9% (OR, 2.27; 95% CI, 1.05-4.89); Pseudomonas spp., 3.0% versus 7.6% (OR, 3.49; 95% CI, 3.49-240.50); and Serratia spp., 3.0% versus 5.4% (OR, 20.23; 95% CI, 2.20-186.14). Bacteria isolated after ≥48 hours of hospitalization were less susceptible to all tested antimicrobial drugs, except for imipenem. CONCLUSIONS AND CLINICAL IMPORTANCE: Decreased antimicrobial susceptibility of bacteria isolated after ≥48 hours of hospitalization provides a rationale for repeated bacteriological culture and susceptibility testing in hospitalized foals with sepsis.


Assuntos
Antibacterianos/uso terapêutico , Bacteriemia/veterinária , Doenças dos Cavalos/tratamento farmacológico , Animais , Animais Recém-Nascidos , Bacteriemia/tratamento farmacológico , Farmacorresistência Bacteriana , Feminino , Doenças dos Cavalos/microbiologia , Cavalos , Hospitalização , Masculino , Testes de Sensibilidade Microbiana/veterinária , Registros/veterinária , Estudos Retrospectivos
17.
Appl Environ Microbiol ; 86(8)2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32033947

RESUMO

A nationwide study on the occurrence of extended-spectrum ß-lactamase (ESBL)/AmpC in nonhospitalized horses in the Netherlands was performed. Molecular characterization was done, and questionnaires were analyzed to identify factors associated with carriage. In total, 796 horse owners were approached; 281 of these submitted a fecal sample from their horse(s), resulting in 362 samples. All samples were cultured qualitatively in Luria-Bertani (LB) broth and subsequently on MacConkey agar, both supplemented with 1 mg/liter cefotaxime (LB+ and MC+). Positive samples were subsequently cultured quantitatively on MC+. Initial extended-spectrum-ß-lactamase (ESBL)/AmpC screening was performed by PCR, followed by whole-genome sequencing on selected strains. Associations between ESBL/AmpC carriage and questionnaire items were analyzed using a univariate generalized estimating equation (GEE) regression analysis, followed by a multiple GEE model for relevant factors. In total, 39 of 362 samples (11%) were determined to be positive for ESBL/AmpC. bla CTX-M-1-carrying isolates were obtained from 77% of positive samples (n = 30). Other ESBL/AmpC genes observed included bla CTX-M-2, bla CTX-M-14, bla CTX-M-15, bla CTX-M-32, bla SHV-12, bla CMY-2, and bla ACT-10 A high association between the presence of bla CTX-M-1 and IncHI1 plasmids was observed (46% of samples; n = 18). Based on core genome analysis (n = 48 isolates), six Escherichia coli clusters were identified, three of which represented 80% of the isolates. A negative association between ESBL/AmpC carriage and horses being in contact with other horses at a different site was observed. The presence of a dog on the premises and housing in a more densely human-populated region were positively associated.IMPORTANCE Extended-spectrum ß-lactamases (ESBLs) are widespread in human and animal populations and in the environment. Many different ESBL variants exist. The dissemination of ESBLs within and between populations and the environment is also largely influenced by genetic mobile elements (e.g., plasmids) that facilitate spread of these ESBLs. In order to identify potential attributable ESBL sources for, e.g., the human population, it is important to identify the different ESBL variants, the bacteria carrying them, and the potential risk factors for ESBL carriage from other potential sources. This nationwide study focuses on ESBL carriage in the open horse population and investigated the molecular characteristics, geographical distribution throughout the Netherlands, and potential risk factors for fecal ESBL carriage in horses. These data can be used for future attribution studies in order to reduce potential transmission of ESBL-producing bacteria between sources.


Assuntos
Infecções por Escherichia coli/veterinária , Fezes/microbiologia , Doenças dos Cavalos/epidemiologia , Animais , Proteínas de Bactérias/metabolismo , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/metabolismo , Doenças dos Cavalos/microbiologia , Cavalos , Países Baixos/epidemiologia , beta-Lactamases/metabolismo
18.
J Vet Diagn Invest ; 32(2): 230-238, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32081091

RESUMO

The role of type A Clostridium perfringens in canine acute hemorrhagic diarrhea syndrome and foal necrotizing enteritis is poorly characterized. However, a highly significant association between the presence of novel toxigenic C. perfringens and these specific enteric diseases has been described. These novel toxigenic strains produce 3 novel putative toxins, which have been designated NetE, NetF, and NetG. Although not conclusively demonstrated, current evidence suggests that NetF is likely the major virulence factor in strains responsible for canine acute hemorrhagic diarrhea syndrome and foal necrotizing enteritis. NetF is a beta-pore-forming toxin that belongs to the same toxin superfamily as CPB and NetB toxins produced by C. perfringens. The netF gene is encoded on a conjugative plasmid that, in the case of netF, also carries another putative toxin gene, netE. In addition, these strains consistently also carry a cpe tcp-conjugative plasmid, and a proportion also carry a separate netG tcp-conjugative plasmid. The netF and netG genes form part of a locus with all the features of the pathogenicity loci of tcp-conjugative plasmids. The netF-positive isolates are clonal in origin and fall into 2 clades. Disease in dogs or foals can be associated with either clade. Thus, these are strains with unique virulence-associated characteristics associated with serious and sometimes fatal cases of important enteric diseases in 2 animal species.


Assuntos
Infecções por Clostridium/veterinária , Clostridium perfringens/fisiologia , Diarreia/veterinária , Doenças do Cão , Enterite/veterinária , Doenças dos Cavalos , Animais , Infecções por Clostridium/diagnóstico , Infecções por Clostridium/microbiologia , Diarreia/diagnóstico , Diarreia/microbiologia , Doenças do Cão/diagnóstico , Doenças do Cão/microbiologia , Cães , Enterite/diagnóstico , Enterite/microbiologia , Doenças dos Cavalos/diagnóstico , Doenças dos Cavalos/microbiologia , Cavalos , Necrose/diagnóstico , Necrose/microbiologia , Necrose/veterinária
19.
mBio ; 11(1)2020 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-32098825

RESUMO

Potomac horse fever (PHF), a severe and frequently fatal febrile diarrheal disease, has been known to be caused only by Neorickettsia risticii, an endosymbiont of digenean trematodes. Here, we report the cell culture isolation of a new Neorickettsia species found in two locations in eastern Ontario, Canada, in 2016 and 2017 (in addition to 10 variable strains of N. risticii) from N. risticii PCR-negative horses with clinical signs of PHF. Gene sequences of 16S rRNA and the major surface antigen P51 of this new Neorickettsia species were distinct from those of all previously characterized N. risticii strains and Neorickettsia species, except for those from an uncharacterized Neorickettsia species culture isolate from a horse with PHF in northern Ohio in 1991. The new Neorickettsia species nonetheless had the characteristic intramolecular repeats within strain-specific antigen 3 (Ssa3), which were found in all sequenced Ssa3s of N. risticii strains. Experimental inoculation of two naive ponies with the new Neorickettsia species produced severe and subclinical PHF, respectively, and the bacteria were reisolated from both of them, fulfilling Koch's postulates. Serological assay titers against the new Neorickettsia species were higher than those against N. risticii Whole-genome sequence analysis of the new Neorickettsia species revealed unique features of this bacterium compared with N. risticii We propose to classify this new bacterium as Neorickettsia finleia sp. nov. This finding will improve the laboratory diagnosis of and vaccine for PHF, environmental risk assessment of PHF, and understanding of PHF pathogenesis and Neorickettsia biology in general.IMPORTANCE Despite the detection of Neorickettsia species DNA sequences in various trematode species and their hosts, only three Neorickettsia species have been cell culture isolated and whole-genome sequenced and are known to infect mammals and/or cause disease. The molecular mechanisms that enable the obligatory intracellular bacterium Neorickettsia to colonize trematodes and to horizontally transmit from trematodes to mammals, as well as the virulence factors associated with specific mammalian hosts, are unknown. Potomac horse fever (PHF) is a severe and acute systemic infectious disease of horses, with clinical signs that include diarrhea. Neorickettsia risticii is the only known bacterial species that causes PHF. Ingestion of insects harboring N. risticii-infected trematodes by horses leads to PHF. Our discovery of a new Neorickettsia species that causes PHF and whole-genome sequence analysis of this bacterium will improve laboratory diagnosis and vaccine development for PHF and will contribute to our understanding of Neorickettsia ecology, pathogenesis, and biology.


Assuntos
Infecções por Anaplasmataceae/microbiologia , Doenças dos Cavalos/microbiologia , Neorickettsia/classificação , Neorickettsia/genética , Neorickettsia/isolamento & purificação , Filogenia , Infecções por Anaplasmataceae/diagnóstico , Animais , Antígenos de Bactérias/genética , Canadá , DNA Bacteriano/análise , Modelos Animais de Doenças , Feminino , Doenças dos Cavalos/diagnóstico , Cavalos , Masculino , Neorickettsia/patogenicidade , Neorickettsia risticii/genética , Neorickettsia risticii/isolamento & purificação , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Análise de Sequência , Trematódeos/microbiologia , Sequenciamento Completo do Genoma
20.
J Vet Diagn Invest ; 32(2): 239-245, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32052697

RESUMO

Enteric disease in horses may be caused by a variety of microorganisms, including several clostridial species. Paeniclostridium sordellii (previously Clostridium sordellii) has been frequently associated with gas gangrene in humans and several animal species, including horses. However, its role in enteric diseases of animals has not been fully determined. We describe herein 7 cases of enteric disease in horses associated with P. sordellii infection. Grossly, the small and/or large intestines were necrotic, hemorrhagic, and edematous. Microscopically, there was severe mucosal necrosis and hemorrhage of the small and/or large intestine of all horses. P. sordellii was isolated and/or demonstrated by immunohistochemistry and/or PCR in the intestine of all horses. All other known causes of enteric disease in horses were ruled out in these 7 cases. P. sordellii should be considered among the differential diagnoses in cases of enteric disease in horses.


Assuntos
Infecções por Clostridium/veterinária , Clostridium/fisiologia , Enterocolite/veterinária , Doenças dos Cavalos/diagnóstico , Animais , Infecções por Clostridium/diagnóstico , Infecções por Clostridium/microbiologia , Clostridium sordellii , Diagnóstico Diferencial , Enterocolite/diagnóstico , Enterocolite/microbiologia , Doenças dos Cavalos/microbiologia , Cavalos , Intestino Grosso/patologia , Intestino Delgado/patologia
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