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1.
J Med Microbiol ; 68(7): 1003-1011, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31172912

RESUMO

PURPOSE: The present study aimed to establish pretreatment protocols as well as real-time and droplet digital polymerase chain reaction (PCR) methodologies to detect and quantify Erysipelothrix rhusiopathiae (ER) DNA in blood samples from infected chickens, as tools for routine diagnostics and monitoring of experimental infections. Chicken blood is a problematic matrix for PCR analysis because nucleated erythrocytes contribute large amounts of host DNA that inhibit amplification. METHODOLOGY: Using artificially spiked samples of fresh chicken blood, as well as blood samples from three experimental infection studies, the performance of pretreatment protocols, including choice of blood stabilization agent, centrifugation speeds and Ficoll gradient separation, was evaluated. The results were compared with those from traditional culture-based protocols combined with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS).Results/Key findings. Simple preparations producing cell-free samples performed well on artificial spike-in samples, providing high sensitivity. However, performance was poor in clinical samples or artificial samples where the bacteria were incubated for 4 h or more in fresh blood prior to DNA extraction. In these samples, a Ficoll separation protocol that creates samples rich in lymphocytes, monocytes and thrombocytes prior to DNA extraction was far more effective. CONCLUSIONS: Our results indicate that ER bacteria undergo rapid phagocytosis in chicken blood and that analysis of a blood fraction enriched for phagocytic cells is necessary for reliable detection and quantification. The presented results explain the poor performance of PCR detection reported in previously published experimental ER infection studies, and the proposed solutions are likely to have broader implications for PCR-based veterinary diagnostics in non-mammalian host species such as poultry and fish.


Assuntos
Galinhas/microbiologia , DNA Bacteriano/genética , Infecções por Erysipelothrix/microbiologia , Erysipelothrix/genética , Reação em Cadeia da Polimerase/veterinária , Doenças das Aves Domésticas/microbiologia , Animais , Erysipelothrix/isolamento & purificação , Infecções por Erysipelothrix/diagnóstico , Eritrócitos/citologia , Eritrócitos/microbiologia , Reação em Cadeia da Polimerase/métodos
2.
Acta Vet Scand ; 61(1): 25, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31146786

RESUMO

BACKGROUND: Although artificial insemination (AI) was developed as a means of controlling disease transmission, pathogens can still be transmitted to females in semen used for AI. In addition, bacteria can cause deterioration in sperm quality during storage. Semen becomes contaminated by the male's normal bacterial flora as it passes out of the reproductive tract but potential pathogens may also contaminate the semen. Therefore, semen samples from stallions to be used for AI are tested before the breeding season to minimize transmission of pathogens to inseminated mares. In Sweden, semen samples are tested at the National Veterinary Institute, Uppsala (SVA). For the present study, a retrospective analysis was made of potentially pathogenic bacteria isolated from samples submitted to the SVA from 2007 to 2017. RESULTS: In our study, Taylorella equigenitalis was found infrequently (53 out of 25,512 samples), representing 11 out of 2308 stallions. If T. equigenitalis was detected, the stallions were treated with antibiotics and re-tested later in the same year. Klebsiella pneumoniae and beta haemolytic streptococci were the most commonly found potential pathogens, whereas Pseudomonas aeruginosa was also isolated occasionally. There were considerable differences in the number of species isolated each year. CONCLUSIONS: Potential pathogens were identified in relatively few of the samples submitted to SVA during this period, with T. equigenitalis not being identified since 2015. Of the other potential pathogens, K. pneumoniae and beta haemolytic streptococci were the most common. The information is relevant for determining guidelines on the testing and treatment of stallions before breeding.


Assuntos
Infecções Bacterianas/veterinária , Fenômenos Fisiológicos Bacterianos , Líquidos Corporais/microbiologia , Genitália Masculina/microbiologia , Doenças dos Cavalos/microbiologia , Infecções do Sistema Genital/veterinária , Sêmen/microbiologia , Animais , Antibacterianos/uso terapêutico , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Doenças dos Cavalos/diagnóstico , Doenças dos Cavalos/tratamento farmacológico , Cavalos , Inseminação Artificial , Masculino , Infecções do Sistema Genital/diagnóstico , Infecções do Sistema Genital/tratamento farmacológico , Infecções do Sistema Genital/microbiologia , Suécia
3.
Avian Pathol ; 43(3): 231-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24661145

RESUMO

This study investigated organic laying hen farms for the presence of Erysipelothrix rhusiopathiae in the house environment and from potential carriers (i.e. insects and mice) during ongoing erysipelas outbreaks, and compared the obtained isolates with those from laying hens. The samples were investigated by selective culture followed by species-specific polymerase chain reaction on cultures. E. rhusiopathiae was isolated from the spleen, jejunal contents, manure, dust and swabs from water nipples. Three more samples from the house environment tested positive by polymerase chain reaction compared with selective culture alone. Selected isolates were investigated by pulsed-field gel electrophoresis (PFGE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). One farm was represented by isolates from laying hens only, and one of these isolates differed in one PFGE band from the others. Different banding patterns were observed for isolates from laying hens and manure on one farm. On the remaining two farms, the isolates from the house environment and laying hens were identical but differed between farms. Outbreaks reoccurred in the next flock on two of the farms, and different PFGE types were isolated from consecutive flocks. Our results suggest an external source of infection, which would explain the previously reported increased risk of outbreaks in free-range flocks. Contaminated manure and dust may represent sources of transmission. For the isolates, MALDI-TOF MS and biochemical typing results were in agreement but, since the type strain of Erysipelothrix tonsillarum was typed as E. rhusiopathiae using MALDI-TOF MS, further studies into this method are needed.


Assuntos
Galinhas/microbiologia , Surtos de Doenças/veterinária , Infecções por Erysipelothrix/epidemiologia , Erysipelothrix/isolamento & purificação , Doenças das Aves Domésticas/epidemiologia , Criação de Animais Domésticos , Animais , Análise por Conglomerados , Eletroforese em Gel de Campo Pulsado/veterinária , Erysipelothrix/classificação , Erysipelothrix/genética , Infecções por Erysipelothrix/microbiologia , Feminino , Camundongos , Doenças das Aves Domésticas/microbiologia , Especificidade da Espécie , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/veterinária
4.
Artigo em Inglês | MEDLINE | ID: mdl-23240071

RESUMO

In a herd of 20 sheep in Sweden, a country where brucellosis has never been diagnosed in sheep or goats, a total of six sheep were found serologically positive to Brucella melitensis in two different rounds of sampling. Yersinia enterocolitica serotype O:9 could at the time of the second sampling be isolated from four sheep, one of them at the same time serologically positive for B. melitensis. The article describes the case and gives some background information on brucellosis and Y. enterocolitica in general as well as a more specific description of the Swedish surveillance program for B. melitensis and the test procedures used. The problem with false-positive reactions, in particular its implications for surveillance programs in low prevalence or officially brucellosis-free countries, is discussed.

5.
Acta Vet Scand ; 53: 45, 2011 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-21718487

RESUMO

BACKGROUND: Treatment and protection of wounds in horses can be challenging; protecting bandages may be difficult to apply on the proximal extremities and the body. Unprotected wounds carry an increased risk of bacterial contamination and subsequent infection which can lead to delayed wound healing. Topical treatment with antimicrobials is one possibility to prevent bacterial colonization or infection, but the frequent use of antimicrobials ultimately leads to development of bacterial resistance which is an increasing concern in both human and veterinary medicine. METHODS: Standardized wounds were created in 10 Standardbred mares. Three wounds were made in each horse. Two wounds were randomly treated with LHP® or petrolatum and the third wound served as untreated control. All wounds were assessed daily until complete epithelization. Protocol data were recorded on day 2, 6, 11, 16, 21 and 28. Data included clinical scores for inflammation and healing, photoplanimetry for calculating wound areas and swab cytology to assess bacterial colonization and inflammation. Bacterial cultures were obtained on day 2, 6 and 16. RESULTS: Mean time to complete healing for LHP® treated wounds was 32 days (95%CI=26.9-37.7). Mean time to complete healing for petrolatum and untreated control wounds were 41.6 days (95%CI=36.2-47.0) and 44.0 days (95%CI=38.6-49.4) respectively. Wound healing occurred significantly faster in LHP® wounds compared to both petrolatum (p=0.0004) and untreated controls (p<0.0001). There was no significant difference in time for healing between petrolatum and untreated controls. Total scores for bacteria and neutrophils were significantly (p<0.0001) lower for LHP® treated wounds compared to petrolatum from day 16 and onwards. Staphylococcus aureus and Streptococcus zooepidemicus were only found in cultures from petrolatum treated wounds and untreated controls. CONCLUSIONS: Treatment with LHP® reduced bacterial colonization and was associated with earlier complete wound healing. LHP® cream appears to be safe and effective for topical wound treatment or wound protection.


Assuntos
Anti-Infecciosos Locais/uso terapêutico , Emolientes/uso terapêutico , Cavalos/lesões , Peróxido de Hidrogênio/uso terapêutico , Lesões do Pescoço/veterinária , Vaselina/uso terapêutico , Cicatrização , Administração Cutânea , Animais , Anti-Infecciosos Locais/administração & dosagem , Bactérias/classificação , Bactérias/isolamento & purificação , Emolientes/administração & dosagem , Epitélio/efeitos dos fármacos , Epitélio/microbiologia , Epitélio/patologia , Feminino , Peróxido de Hidrogênio/administração & dosagem , Inflamação/tratamento farmacológico , Inflamação/veterinária , Lesões do Pescoço/tratamento farmacológico , Lesões do Pescoço/microbiologia , Lesões do Pescoço/patologia , Vaselina/administração & dosagem , Distribuição Aleatória , Cicatrização/efeitos dos fármacos
6.
Bioresour Technol ; 99(16): 7859-65, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18513960

RESUMO

The aim of the study was to assess the effect of pasteurisation, as set by the European regulation EC 1774/2002, on selected pathogens and indicator organisms. Unpasteurised substrate (biowaste), including animal by-products from a full-scale biogas plant was heat treated under laboratory conditions at 70 degrees C and 55 degrees C for 30 min and 60 min. Heat treatment at 55 degrees C for 60 min was not sufficient to achieve a hygienically acceptable product. Heat treatment at 70 degrees C for 30 min and 60 min was effective in reducing pathogenic bacteria, Ascaris suum eggs, Swine vesicular disease virus and indicator organisms. However, this level of pasteurisation will still not reduce the quantity of Clostridia spores, or completely inactivate heat-resistant viruses such as Porcine parvovirus or Salmonella phage 28B. The results still give cause for some concern regarding the use of digested residue from biogasplants in agriculture.


Assuntos
Ascaris suum/fisiologia , Bactérias/patogenicidade , Fezes , Temperatura Alta , Parasitos/patogenicidade , Eliminação de Resíduos/métodos , Vírus/patogenicidade , ADP Ribose Transferases/isolamento & purificação , Anaerobiose , Animais , Bactérias/isolamento & purificação , Biodegradação Ambiental , Reatores Biológicos , Clostridium/classificação , Clostridium/isolamento & purificação , Clostridium/patogenicidade , Contagem de Colônia Microbiana , Enterovirus Humano B/patogenicidade , Escherichia coli O157/isolamento & purificação , Escherichia coli O157/patogenicidade , Fezes/microbiologia , Fezes/parasitologia , Fezes/virologia , Guias como Assunto/normas , Humanos , Listeria monocytogenes/isolamento & purificação , Listeria monocytogenes/patogenicidade , Óvulo/fisiologia , Parasitos/isolamento & purificação , Parvovirus Suíno/patogenicidade , Sobrevida , Suínos , Fatores de Tempo , Fatores de Virulência/isolamento & purificação , Vírus/isolamento & purificação
7.
BMC Microbiol ; 6: 47, 2006 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-16737528

RESUMO

BACKGROUND: Clostridium perfringens, a serious pathogen, causes enteric diseases in domestic animals and food poisoning in humans. The epidemiological relationship between C. perfringens isolates from the same source has previously been investigated chiefly by pulsed-field gel electrophoresis (PFGE). In this study the genetic diversity of C. perfringens isolated from various animals, from food poisoning outbreaks and from sludge was investigated. RESULTS: We used PFGE to examine the genetic diversity of 95 C. perfringens type A isolates from eight different sources. The isolates were also examined for the presence of the beta2 toxin gene (cpb2) and the enterotoxin gene (cpe). The cpb2 gene from the 28 cpb2-positive isolates was also partially sequenced (519 bp, corresponding to positions 188 to 706 in the consensus cpb2 sequence). The results of PFGE revealed a wide genetic diversity among the C. perfringens type A isolates. The genetic relatedness of the isolates ranged from 58 to 100% and 56 distinct PFGE types were identified. Almost all clusters with similar patterns comprised isolates with a known epidemiological correlation. Most of the isolates from pig, horse and sheep carried the cpb2 gene. All isolates originating from food poisoning outbreaks carried the cpe gene and three of these also carried cpb2. Two evolutionary different populations were identified by sequence analysis of the partially sequenced cpb2 genes from our study and cpb2 sequences previously deposited in GenBank. CONCLUSION: As revealed by PFGE, there was a wide genetic diversity among C. perfringens isolates from different sources. Epidemiologically related isolates showed a high genetic similarity, as expected, while isolates with no obvious epidemiological relationship expressed a lesser degree of genetic similarity. The wide diversity revealed by PFGE was not reflected in the 16S rRNA sequences, which had a considerable degree of sequence similarity. Sequence comparison of the partially sequenced cpb2 gene revealed two genetically different populations. This is to our knowledge the first study in which the genetic diversity of C. perfringens isolates both from different animals species, from food poisoning outbreaks and from sludge has been investigated.


Assuntos
Animais Domésticos/microbiologia , Infecções por Clostridium/microbiologia , Clostridium perfringens/classificação , Doenças Transmitidas por Alimentos/microbiologia , Variação Genética , Esgotos/microbiologia , Animais , Toxinas Bacterianas/genética , Sequência de Bases , Infecções por Clostridium/epidemiologia , Clostridium perfringens/genética , Clostridium perfringens/isolamento & purificação , DNA Bacteriano/análise , DNA Bacteriano/genética , DNA Ribossômico/análise , Surtos de Doenças , Eletroforese em Gel de Campo Pulsado , Enterotoxinas/genética , Doenças Transmitidas por Alimentos/epidemiologia , Humanos , Dados de Sequência Molecular , RNA Ribossômico 16S/genética
8.
Water Res ; 39(20): 4879-86, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16297957

RESUMO

In Sweden, full-scale, commercial biogas plants (BGP), which process low-risk animal waste, operate a separate pre-pasteurisation at 70 degrees C for 60 min as required by EEC regulation 1774/2002. The purpose of this study was to establish if, during pasteurisation and further processing and handling in full-scale BGPs, pathogens in biowaste could be sufficiently reduced to allow its use on arable land. Four BGPs were sampled on six occasions during 1 year. Sampling was performed from six locations during biogas production. The samples being analysed quantitatively to detect indicator bacteria (Escherichia coli, Enterococcus spp. and coliforms) and spore-forming bacteria (Clostridium spp. and Bacillus spp.) and qualitatively for bacterial pathogens (salmonella, listeria, campylobacter and VTEC O157). Salmonella was the most frequently isolated pathogen before pasteurisation In general, the treatment adequatly reduced both indicator and pathogenic bacteria. Spore-forming bacteria were not reduced. However, recontamination and regrowth of bacteria in biowaste was frequently noted after pasteurisation and digestion.


Assuntos
Eliminação de Resíduos/métodos , Criação de Animais Domésticos , Animais , Bactérias/isolamento & purificação , Reatores Biológicos , Bovinos , Contagem de Colônia Microbiana , Indústria de Laticínios , Fertilizantes , Indústria de Processamento de Alimentos , Resíduos de Alimentos , Temperatura Alta , Esterco/microbiologia , Restaurantes , Suécia , Suínos
9.
Water Res ; 38(8): 1989-94, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15087179

RESUMO

This study surveyed the presence of bacterial pathogens in eight Swedish sewage treatment plants (STPs), with four different treatment methods, focusing on detection of zoonotic bacteria in raw and treated sludge. Salmonella spp., Listeria monocytogenes, Campylobacter coli and jejuni, Escherichia coli O157 and indicator bacteria were investigated. Samplings were performed from July 2000 to June 2002, resulting in 64 raw sludge samples and 69 treated sludge samples. The samples from raw sludge (67%) and treated sludge (55%) were positive for Salmonella; 49 different serotypes were detected. Restriction enzyme analysis and pulsed field gel electrophoresis of Salmonella serotypes indicated that Salmonella persists in STPs and that there is a continuous supply of new strains. There are differences in treatment methods concerning the reduction of pathogens and indicator bacteria. If spread on arable land, sludge increases the environmental load of pathogens; this increases the risk for spreading diseases to people and animals.


Assuntos
Bactérias/isolamento & purificação , Esgotos/microbiologia , Animais , Bactérias/patogenicidade , Campylobacter/isolamento & purificação , Campylobacter/patogenicidade , Escherichia coli O157/isolamento & purificação , Escherichia coli O157/patogenicidade , Humanos , Incidência , Listeria/isolamento & purificação , Listeria/patogenicidade , Plantas , Controle de Qualidade , Risco , Salmonella/isolamento & purificação , Salmonella/patogenicidade , Sorotipagem , Suécia , Gerenciamento de Resíduos , Microbiologia da Água
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