Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “veterinary pathogens”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 307 records · Page 17Linked to original sources
PubMed2004

Anthrax in Wabessa village in the Dessie Zuria district of Ethiopia.

In 2002 an investigation of sudden death in a goat in Wabessa village in the Dessie Zuria district of Ethiopia was undertaken using fresh blood brought to the Kombolcha Regional Veterinary Laboratory. The sample was examined using standard bacteriological techniques and animal pathogenicity tests were also performed. The laboratory investigation revealed Bacillus anthracis as the cause of sudden death. Information gathered from stockowners in the same village revealed other similar recent cases and deaths, both in animals and humans, with farmers clearly describing the clinical signs and necropsy findings of anthrax. The disease occurs annually in this area in May and June, and in the 2002 outbreak mortality rates of 7.7%, 32.7% and 47.1% were observed in cattle, goats and donkeys, respectively. This study indicates that the community of this particular village neither knows of, nor practises, any of the conventional methods for anthrax control. The cutaneous form of the disease in humans and the environmental contamination associated with the practise of opening cadavers are briefly described and the findings are discussed with reference to the epidemiology of anthrax in both Ethiopia and elsewhere. Control strategies are also recommended.

Adult↗
PubMed1980

Criteria for selecting the animal to meet the research need.

Prior to designing any study which utilizes animals, a number of criteria should be considered. One should decide whether alternatives to intact animal usage (tissue culture systems or mathematical models) will provide acceptable results. Perhaps there is a naturally-occurring animal model which resembles the condition to be studied. Careful consideration should then be made to select the correct animal species, the genotypic, microbial status and numbers of such animals needed. Once the study has been completed, these animal-related factors should be considered when interpreting the data.

Animals↗
PubMed2006

Nested polymerase chain reaction for detection of pathogenic leptospires.

Leptospirosis is a widespread zoonosis caused by pathogenic members of the genus Leptospira that has a great impact on human and veterinary public health. Early diagnosis of leptospirosis is important because severe lepto spiral infection can have a fulminant course. The available serological techniques for the diagnosis of leptospirosis have low sensitivity during the early stage of the disease. Efforts are being made to develop simpler, effective, efficient, and inexpensive diagnostic methods. In this work, we first evaluate a polymerase chain reaction (PCR) based method for diagnosis of leptospirosis. Primers were designed to amplify a 264 bp region within the lipL32 gene that is conserved among pathogenic Leptospira and absent in nonpathogenic species. The sensitivity and specificity of the assay were evaluated using 7 saprophytic serovars, 37 pathogenic serovars, and 15 other microorganisms. The method was very specific for pathogenic serovars, however, it lacked sensitivity. To enhance the sensitivity, another primer pair was designed to amplify a 183 bp region within the 264 bp region of the lipL32 gene and was used in a nested PCR assay. This approach was much more sensitive than conventional PCR.

Animals↗
PubMed1978

[Recombinant DNA studies, a controversial subject which is also promising from the point of view of veterinary medicine (author's transl)].

The hereditary characters of organisms are bound up in the DNA of their genomes. Genetic information is expressed by a complicated mechanism. The process by which this occurs and the control of the degree of expression in bacteria and a number of the other lower organisms are known only in broad outline. There usually is no exchange of DNA between organisms of unrelated species in nature. "Foreign" DNA can be linked to bacterial plasmid DNA and multiplied in the laboratory as a recombinant DNA molecule in bacteria using the recently discovered so-called restriction enzymes. Expression of bacterial DNA can thus be accomplished in a different, unrelated bacterium. In principle, this means that the natural barriers between unrealated species of organisms may be passed by. Human and animal DNA can also be multiplied in bacteria by this method. Previous recombinant DNA studies showed that the mode of expression of genetic information in the higher organisms differs markedly from that in bacteria. The initially sanguine expectations regarding the practical use of recombinant DNA research, for instance in the production of biologically important substances by bacteria, will therefore possibly not be realized at short notice. On the other hand this technique has added considerably to the knowledge of expression of genes within a short space of time. This is particularly true of the mechanisms of pathogenicity of E. coli, the bacterium which plays such an important role in veterinary medicine. The recombinant DNA technique is briefly reviewed in the present paper. The uses are broadly outlined, and one of these, which could be of importance in veterinary medicine, is described in greater detail. International discussions of potential hazards, and therefore also of the admissibility of this type of experiment, are griefly summarized.

Animals↗
PubMed1999

[Antimicrobial susceptibility of a selection of Salmonella enterica strains of various origins isolated in Spain].

The widespread use of antimicrobials in human and veterinary practice is increasingly causing the emergence of different multidrug-resistant human pathogens. This situation makes treating infections caused by these microorganisms difficult. Salmonella enterica is an ubiquitous organism and may be a good indicator of the influence of the use and abuse of antimicrobials on the appearance of multiresistant strains. One hundred and ninety S. enterica strains of different origins isolated in Spain in 1996 were randomly selected. The minimal inhibitory concentration (MIC) was studied using the agar dilution method according to NCCLS criteria in the following antimicrobials: ampicillin, ticarcillin, amoxicillin-clavulanic acid, cefazolin, cefuroxime, cefotaxime, imipenem, gentamicin, apramycin, ciprofloxacin, streptomycin, chloramphenicol, tetracycline, sulfamethoxazole and co-trimoxazole. Sixty-three percent of the S. enterica tested were resistant and 24% were multiresistant. The percentage of resistant and multiresistant strains of S. enterica of human origin was slightly higher than those of nonhuman origin. Statistically, ampicillin, ticarcillin and amoxicillin-clavulanic acid were significantly more resistant in strains of human origin. Ninety-one percent of the strains of Typhimurium serotype and phagotype 104 were multiresistant. The Salmonella Typhimurium serotype and phagotype 104 ACSTSu-resistant clone, which is widespread in various Western countries, was also isolated in this study. The use of different antimicrobials in human and veterinary practice needs to be rationalized.

Anti-Bacterial Agents↗
PubMed2004

Molecular epidemiology of antimicrobial resistance in veterinary medicine: where do we go?

Molecular epidemiology allows us to trace specific microorganisms and mobile genetic elements and to assess their epidemiological and evolutionary relationships. Examples of molecular epidemiology investigations in veterinary hospitals are discussed. They demonstrate the great similarities with the situation in human medicine and the potential usefulness of molecular epidemiology in our fight against antimicrobial resistance and nosocomial infections in veterinary hospitals. A broad knowledge of the diversity of antimicrobial resistance determinants in some major groups of pathogens and commensals from animals such as Enterobacteriaceae, Pasteurellaceae, enterococci and staphylococci is emerging. However, there are important gaps in this knowledge, which are discussed here. Many more molecular epidemiology studies will be necessary to understand and follow the evolution of the problem in veterinary medicine and agriculture on a global scale. To be able to build useful surveillance programs and reliable epidemiological models, and to identify critical intervention points, we need to improve our understanding of antimicrobial resistance at the animal and farm levels. Studies assessing the dynamics of bacterial populations and of resistance determinants at these levels are desperately needed. Understanding the relationships between antimicrobial resistance, colonization factors, and virulence also represents a major issue for which molecular epidemiology investigations will be needed.

Animals↗
PubMed2004

Food safety and animal production systems: controlling zoonoses at farm level.

Controlling zoonotic agents in animal and poultry reservoirs has the effect of reducing the challenge to food safety management systems in processing and further along the food chain. Producing and maintaining healthy stock requires good husbandry practices, which include stock selection and veterinary attention. Feed is a key input, both as a source of pathogen-free nutrients and as a balanced dietto maintain healthy livestock. Safe water, appropriate vermin and wildlife control and an optimum environment to reduce stress are important if animals are to perform. Farms are not sterile environments and initiatives to reduce the zoonotic hazards have to be practical, economically feasible and flexible, depending on the scale of the enterprise, the species being farmed, and the epidemiology of the zoonotic agents in the particular geographical region. Education of farmers and stockmen is crucial to successful on-farm control of zoonoses, as an understanding of why control measures are necessary, and how they can be applied, will improve compliance with protocols and procedures. This understanding is a first step towards the implementation of a longitudinal integrated food safety assurance approach to zoonosis control in the pre-harvest phase of the food chain.

Animal Diseases↗
PubMed2001

Emergence of Salmonella typhimurium definitive type 104 (DT104) as an important cause of salmonellosis in horses in Ontario.

Salmonella Typhimurium definitive type 104 (DT104) has emerged as a common cause of salmonellosis in humans and cattle, yet previous reports involving horses are sparse. This study reports the emergence of DT104 as an important pathogen in horses in Ontario. The first clinical case of DT104 infection at the Ontario Veterinary College was identified in 1997. Seventeen cases of DT104-associated salmonellosis were identified between 1997 and 2000. In 2000, 12 of 13 cases of salmonellosis were due to DT104. Salmonellosis in horses due to DT104 is of concern, since the organism is multiresistant to antibiotics and poses increased zoonotic risk. Phage type distribution of Salmonella isolates should be monitored to determine whether DT104 will remain a prevalent equine pathogen.

Animals↗
PubMed2005

Cellular adhesive phenomena in apicomplexan parasites of red blood cells.

The apicomplexan parasites Babesia and Plasmodium are related, yet phylogenetically distinct haemoprotozoa that infect red blood cells and cause severe diseases of major human and veterinary importance. A variety of cellular and molecular interactions are pivotal in many aspects of the pathogenicity of these two parasites. Comparison of the cellular and molecular mechanisms that culminate in accumulation of parasitised red blood cells in the microvasculature of cattle infected with Babesia bovis (babesiosis) and humans infected with Plasmodium falciparum (falciparum malaria) is particularly instructive given the striking similarities in the pathophysiology of these two important medical and veterinary diseases. While such adhesive phenomena have been studied extensively in malaria, they have received relatively little attention in babesiosis. In this review, we summarise the findings of more than 25 years of research into cellular adhesive phenomena in malaria and speculate on how this body of work can now be applied to Babesia parasites. Such information is fundamental if we are to learn more about the biology of Babesia parasites, the cellular and molecular mechanisms by which they cause infection and disease and how to develop novel therapeutic strategies or vaccines for both Babesia and malaria infections.

Animals↗
PubMed2004

Antiviral therapy for ocular viral disease.

Ophthalmic manifestations of viral disease are commonly encountered in veterinary practice. Although the number of antiviral agents is rapidly increasing, the efficacy of many of these drugs against animal viral pathogens may not be known. Furthermore, some of these newer medications may, in fact. be toxic to animal patients. Continued research on the efficacy of these medications in treating viral diseases of veterinary importance is warranted.A thorough review of the ever-growing body of literature is imperative before instituting any new or unknown antiviral therapy. At this time, feline HSV-1 infections remain the most well understood of the ocular viral infections that veterinary practitioners may be called on to treat. Ironically, the number of antiviral agents proven to be effective in naturally occurring clinical cases of FHV-I remains quite limited. With new medications being investigated, this paucity of information on efficacious antiviral therapeutic agents will hopefully improve.

Administration, Topical↗
PubMed2004

Advances in mucosal vaccination.

Pathogens that enter the body via mucosal surfaces face unique defense mechanisms that combine the innate barrier provided by the mucus layer with an adaptive response typified by the production and transepithelial secretion of pathogen-specific IgA. Both the measurement and induction of mucosal responses pose significant challenges for experimental and practical application and may need to be adapted to the species under study. In particular, for livestock, immunization procedures developed in small rodent models are not always effective in large animals or compatible with management practices. This paper reviews the latest advances in our understanding of the processes that lead to secretory IgA responses and how this relates to the development of mucosal immunization procedures and adjuvants for veterinary vaccines. In addition, it highlights the complex interactions that can take place between the pathogen and the host's immune response, with specific reference to Chlamydia/Chlamydophila infections in sheep.

Animals↗
PubMed1992

Spread of a newly found trimethoprim resistance gene, dhfrIX, among porcine isolates and human pathogens.

A plasmid-borne gene mediating trimethoprim resistance, dhfrIX, newly found among porcine strains of Escherichia coli, was observed at a frequency of 11% among trimethoprim-resistant veterinary isolates. This rather high frequency of dhfrIX could be due to the extensive use of trimethoprim in veterinary practice in Sweden. After searching several hundred clinical isolates, one human E. coli strain was also found to harbor the dhfrIX gene. Thus, the dhfrIX gene seems to have spread from porcine bacteria to human pathogens. Furthermore, the occurrence of other genes coding for resistant dihydrofolate reductase enzymes (dhfrI, dhfrII, dhfrV, dhfrVII, and dhfrVIII) among the porcine isolates was investigated. In addition, association of dhfr genes with the integraselike open reading frames of transposons Tn7 and Tn21 was studied. In colony hybridization experiments, both dhfrI and dhfrII were found associated with these integrase genes. The most common combination was dhfrI and int-Tn7, indicating a high prevalence of Tn7.

Animals↗
PubMed1984

[Role of multiple drug resistance in the biology of pathogenic and opportunistic bacteria].

The significance of cloning of pathogenic and opportunistic multiple drug-resistant bacteria is analysed from the present viewpoints of medicine and veterinary. Distribution of drug-resistant strains in men, animals and environment and occurrence of new type hospital and nosocomial infections are described. The controversial points of the antibiotics role in the formation of multiple drug resistance plasmids, occurrence of hospital resistant strains and the part of R plasmids in changing the biological characteristics of pathogenic and opportunistic bacteria are analysed. It is shown in relation to Salmonella that formation of definite clones of multiple drug resistant bacteria results in significant changing of epidemiology of the diseases caused by these organisms. The data on the identity of the biological and genetic characteristics of the Salmonella strains of some phage vars isolated in hospitals and outside the hospitals, as well as the data on the effect of R plasmids on the Salmonella virulence are presented. The thesis of a higher infective capacity of the strains with multiple drug resistance associated with their increased survival levels and a higher colonization ability is accentuated. The danger of occurrence of new type causative agents on formation of complex plasmids with additional determinants connected with the bacteria pathogenicity is discussed. The tasks of the further investigation of these aspects are formulated and the possible means for the control of this phenomenon are presented.

Animals↗
PubMed1995

Poxvirus-based vectors as vaccine candidates.

The safety issues surrounding the use of vaccinia-based vaccine candidates have been significantly addressed with the development of the NYVAC and ALVAC vectors. These vectors can be engineered to express multiple genes from the same pathogen or multiple genes from multiple pathogens. The use of these vectors to develop needed vaccines for human and veterinary medicine remains the focus of studies that are currently in progress.

Animals↗
PubMed1990

Applications of nucleic acid probes in veterinary infectious diseases.

Nucleic acid probe technology is increasingly being used in basic research in veterinary microbiology and in diagnosis of infectious diseases of veterinary importance. This review presents an overview of nucleic acid probe methodology and its applications in veterinary infectious diseases. The major applications of nucleic acid probes include detection of pathogens in clinical samples, especially those organisms which are fastidious and difficult to cultivate, differentiation of virulent from avirulent organisms and vaccine strains from wild type isolates, typing of microorganisms, mapping genes, screening libraries of cloned DNA for specific genes, detection of latently infected or carrier animals, study of mechanisms of pathogenesis, epidemiological studies and food safety.

Animals↗
PubMed1999

Resistance responses of microorganisms in food environments.

Food borne microorganisms display a broad spectrum of resistance responses to naturally occurring and intentionally added antimicrobial agents. Resistance may be conferred by innate structural features of the bacterial strain such as an impermeable outer membrane or a mechanism for antibiotic-inactivation. Bacteria previously susceptible to an antimicrobial compound can acquire resistance through mutation or through genetic transfer processes such as transformation, transduction, and conjugation. Resistance can also be conferred by biofilm formation on food processing surfaces as an adaptive response to protect colonies from cleaning and sanitation. Resistant pathogens are a global problem, facilitated by international trade of raw and processed foods. Cross resistance between clinical and nonclinical antimicrobials can exist and is of concern. The development of resistant foodborne pathogens has been attributed to increased antibiotic use in hospitals, outpatient facilities, and veterinary applications. Resistant microorganisms can also develop as a result of physical processes used in food preservation, such as acid treatments and irradiation processes. Strategies to effectively counter resistance development include: changing current practices of antibiotic usage, developing new antibiotics, applying hurdle preservation approaches, preventing bacterial adhesion, and utilizing competitive exclusion. This paper presents an overview of problems arising from the development of microbial resistance, and explores possible solutions for detecting and defeating the adaptive changes of microorganisms.

Drug Resistance, Microbial↗
PubMedDate not supplied

Tick- and flea-borne rickettsial emerging zoonoses.

Between 1984 and 2004, nine more species or subspecies of spotted fever rickettsiae were identified as emerging agents of tick-borne rickettsioses throughout the world. Six of these species had first been isolated from ticks and later found to be pathogenic to humans. The most recent example is Rickettsia parkeri, recognized as a human pathogen more than 60 years after its initial isolation from ticks. A new spotted fever rickettsia, R. felis was also found to be associated with fleas and to be a human pathogen. Similarly, bacteria within the family Anaplasmataceae have been considered to be of veterinary importance only, yet three species have been implicated in human diseases in recent years, including Ehrlichia chaffeensis, the agent of human monocytic ehrlichiosis, Anaplasma phagocytophilum, the agent of human anaplasmosis (formerly known as "human granulocytic ehrlichiosis agent", E. equi and E. phagocytophila), and finally Ehrlichia ewingii, which causes granulocytic ehrlichiosis in humans. We present here an overview of the various tick- and flea-borne rickettsial zoonoses described in the last 20 years, focusing on the ecological, epidemiological and clinical aspects.

Anaplasmosis↗