Topic:Pathogens
Pathogens are microorganisms, such as bacteria, viruses, fungi, and parasites, that can cause disease in horses. These microorganisms interact with the equine immune system, often leading to a range of health issues that can affect individual horses or entire populations. Pathogens can be transmitted through various routes, including direct contact, vectors, or environmental exposure. Common equine pathogens include Streptococcus equi, Equine Herpesvirus, and Strongylus vulgaris. Understanding the interactions between equine hosts and pathogens is essential for disease prevention, management, and treatment. This page compiles peer-reviewed research studies and scholarly articles that explore the identification, transmission, and impact of pathogens on equine health.
Rhodococcus equi-specific hyperimmune plasma administration decreases faecal shedding of pathogenic R. equi in foals. is the most common cause of pneumonia in young foals. Pneumonic foals are an important source of environmental contamination as they shed higher amounts of in their faeces than unaffected foals. As -specific hyperimmune plasma (HIP) lessens clinical pneumonia, we hypothesise that its use would result in decreased faecal shedding of by foals. Neonatal foals were either given HIP (n=12) or nothing (n=9, control) shortly after birth and were then experimentally infected with Faeces were collected before and on weeks 2, 3, 5 and 7 after infection. Presence of virulent was tested using qPCR. T...
A cross-sectional study of methicillin-resistant Staphylococcus aureus at the equine-human interface. The present study aimed at investigating the percent prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in equines and associated personnel. A total of 150 swabs of equines and 50 nasal swab samples of associated personnel were collected. These samples were processed in mannitol salt broth for enrichment. A total of 175 nasal swab samples changed the broth color from pink to yellow which were detected as samples containing S. aureus. These samples were processed further on specific media, namely mannitol salt agar, Staph-110, and blood agar, for phenotypic and Gram's staining-bas...
Molecular detection of Rickettsia spp., Anaplasma platys and Theileria equi in ticks collected from horses in Tayrona National Park, Colombia. Horses are among the domestic animals that closely interact with humans and are highly parasitized by ticks, which are the primary vectors of zoonoses. As horses in Tayrona National Natural Park (PNNT) are used as a means of transporting goods, luggage and people, they are in constant contact with wild animals, workers and tourists from different countries. These factors increase the transmission risk of hemoparasites. The purpose of this study was to determine the presence of Rickettsia sp., Anaplasma sp., and Theileria sp., in horse ticks in this protected area using conventional PCR. We col...
Effect of Macrolide and Rifampin Resistance on the Fitness of Rhodococcus equi. is a leading cause of severe pneumonia in foals. Standard treatment is dual antimicrobial therapy with a macrolide and rifampin, but the emergence of macrolide- and rifampin-resistant isolates is an increasing problem. The objective of this study was to determine the effect of macrolide and/or rifampin resistance on fitness of Three unique isogenic sets were created, each consisting of four strains, as follows: a susceptible parent isolate, strains resistant to macrolides or rifampin, and a dual macrolide- and rifampin-resistant strain. Each isogenic set's bacterial growth curve was genera...
In vitro antimicrobial susceptibility of equine clinical isolates from France, 2006-2016. This study aimed to analyse antimicrobial susceptibility evolution of equine pathogens isolated from clinical samples from 2006-2016. A collection of 25 813 bacterial isolates was studied, clustered according to their origins (respiratory tract, cutaneous, genital and other), and analysed for their antimicrobial susceptibility using the disk diffusion method. The most frequently isolated pathogens were group C Streptococci (27.6%), Escherichia coli (20.0%), Staphylococcus aureus (7.8%), Pseudomonas aeruginosa (4.0%), Enterobacter spp. (3.4%), Klebsiella pneumoniae (2.4%), and Rhodococcus equi ...
Peripheral caries and disease of the periodontium in Western Australian horses: An epidemiological, anatomical and histopathological assessment. Peripheral caries may cause significant oral pain and pathology and is very prevalent within the Western Australia horse population. Associations with periodontal disease have been indicated; however, further work is needed to assess the anatomical and histological aspects of the conditions, to better understand the pathophysiology. Objective: To assess the anatomical and histopathological changes associated with equine cheek teeth peripheral caries and disease of the periodontium to better understand the pathogenesis and any association between the conditions. Methods: Cross-sectional epidemi...
Hyalomma rufipes on an untraveled horse: Is this the first evidence of Hyalomma nymphs successfully moulting in the United Kingdom? During September 2018, a tick was submitted to Public Health England's Tick Surveillance Scheme for identification. The tick was sent from a veterinarian who removed it from a horse in Dorset, England, with no history of overseas travel. The tick was identified as a male Hyalomma rufipes using morphological and molecular methods and then tested for a range of tick-borne pathogens including; Alkhurma virus, Anaplasma, Babesia, Bhanja virus, Crimean-Congo Haemorrhagic fever virus, Rickettsia and Theileria. The tick tested positive for Rickettsia aeschlimannii, a spotted fever group rickettsia li...
Evaluation of MALDI-TOF MS and an expanded custom reference spectra database for the identification and differentiation of Taylorella equigenitalis and Taylorella asinigenitalis. Misidentification between Taylorella equigenitalis, the causative agent of contagious equine metritis (CEM), and Taylorella asinigenitalis is observed by the gold standard culture method. The performance of matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) for Taylorella species identification was evaluated using 85 T. equigenitalis and 28 T. asinigenitalis strains selected on the basis of multilocus sequence typing data. Seven of the T. equigenitalis and 9 of the T. asinigenitalis strains were used to generate in-house reference spectra to expand ...
Klossiella equi Infecting Kidneys of Ontario Horses: Life Cycle Features and Multilocus Sequence-Based Genotyping Confirm the Genus Klossiella Belongs In the Adeleorina (Apicomplexa: Coccidia). Species in the genus Klossiella Smith and Johnson, 1902 are unique among the suborder Adeleorina because they are monoxenous in mammals exclusively, whereas all other reported members of the Adeleorina use invertebrates as definitive hosts. Unlike other coccidia, all members of the Adeleorina undergo syzygy, the association of microgamonts and macrogamonts before maturation to gametes and syngamy. After fertilization, many members of the Adeleorina produce thin-walled polysporocystic oocysts. Despite being biologically similar to other members of the Adeleorina, the phylogenetic placement of t...
Long term silent carriers of Streptococcus equi ssp. equi following strangles; carrier detection related to sampling site of collection and culture versus qPCR. After strangles outbreaks, Streptococcus equi ssp. equi (S. equi) can persist in clinically normal silent carriers for months to years. Two naturally occurring outbreaks of strangles with 53 and 100% morbidity, respectively, were followed longitudinally to assess occurrence of carrier state and optimal detection methods Outbreak A involved 98 yearling warmbloods, and outbreak B 38 mature Icelandic horses. Fully recovered horses were sampled at least 6 months after index cases using nasal swabs (one sampling occasion only) nasopharyngeal lavage and guttural pouch visualisation and lavages for c...
[Comparative analysis of LAMP and Real Time PCR methods to detect pathogens of glanders and meliodosis.]. Results of detection of Burkholderia mallei and Burkholderia pseudomallei DNA strains by LAMP (Loop-mediated Isothermal Amplification) and Real Time PCR are shown. It has been revealed that, in Real Time PCR, primers steadily detected DNA of those microorganism for the sequences of which they were designed. The above mentioned primers did not detect DNA of heterologous strains. During LAMP method no set of primers showed high analytical sensitivity and specificity. Primers did not detected DNA of all the strains under research to target genes of which they were not intended, but they were capa...
Prevalence, risk factors, and characterization of multidrug resistant and extended spectrum β-lactamase/AmpC β-lactamase producing Escherichia coli in healthy horses in France in 2015. Although antimicrobial resistance is increasingly common in equine medicine, molecular and epidemiological data remains scarce. Objective: We estimated the prevalence of, and risk factors for, shedding of multidrug resistant (MDR), extended spectrum β-lactamase (ESBL)-producing, and AmpC β-lactamase-producing, or some combination of these in Escherichia coli in horses in France. We characterized ESBL/AmpC isolates for antimicrobial susceptibility and the presence of virulence and ESBL/AmpC-associated resistance genes. Methods: Fecal samples from healthy adult horses at 41 premises were colle...
Molecular Detection and Phylogenetic Analysis of Anaplasma phagocytophilum in Horses in Korea. The identification and characterization of pathogenic and zoonotic tick-borne diseases like granulocytic anaplasmosis are essential for developing effective control programs. The differential diagnosis of pathogenic Anaplasma phagocytophilum and non-pathogenic A. phagocytophilum-like Anaplasma spp. is important for implementing effective treatment from control programs. The objective of the present study was to investigate the prevalence of Anaplasma spp. in horses in Korea by nucleotide sequencing and restriction enzyme fragment length polymorphism assay. Of the 627 horses included in the stu...
Effects of 2 preparation methods and long-term storage on structural integrity and bacterial loads of equine amnion. To determine the influence of tissue preparation and long-term storage methods on structural integrity and risk of bacterial contamination of equine amnion. Methods: Prospective experimental investigation SAMPLE POPULATION: Amniotic membranes from 8 healthy mares (n = 440 tested samples). Methods: Samples for baseline bacteriology and histology were taken after removal of debris. The remaining tissue was divided and processed with 0.05% chlorhexidine or 2% iodine/0.25% acetic acid. Processed amnion samples were assigned to 1 of 9 combinations of storage media (saline, chlorhexidine, acetic...
Long live the worms: methods for maintaining and assessing the viability of intestinal stages of Parascaris spp. in vitro. In vitro maintenance of helminth parasites enables a variety of molecular, pharmaceutical and immunological analyses. Currently, the nutritional and environmental in vitro requirements of the equine ascarid parasite, Parascaris spp., have not been determined. Additionally, an objective method for assessing viability of Parascaris spp. intestinal stages does not exist. The purpose of this study was to ascertain the in vitro requirements of intestinal stages of Parascaris spp., and to develop a viability assessment method. A total of 1045 worms were maintained in a total of 212 cultures. Worms o...
Mycotic Rhinitis and Sinusitis in Florida Horses. Rhinitis and sinusitis caused by fungal pathogens were studied in biopsy samples submitted from 52 horses distributed throughout subtropical and tropical regions of Florida. Methods included routine histopathology as well as polymerase chain reaction (PCR) with panfungal/panoomycete primers and DNA sequencing on extracted DNA (DNA barcoding). Granulomatous, pyogranulomatous, and fibrinopurulent lesions in nasal and sinus mucosa were associated with signs of upper airway obstruction and noise as well as nasal discharge. Morphologic and histochemical assessment of cases identified 31 cases of zy...
Data on whole genome sequencing of the oomycete Pythium insidiosum strain CBS 101555 from a horse with pythiosis in Brazil. The oomycete Pythium insidiosum infects humans and animals worldwide, and causes the life-threatening condition, called pythosis. Most patients lose infected organs or die from the disease. Comparative genomic analyses of different P. insidiosum strains could provide new insights into its pathobiology, and can lead to discovery of an effective treatment method. Several draft genomes of P. insidiosum are publicly available: three from Asia (Thailand), and one each from North (the United States) and Central (Costa Rica) Americas. We report another draft genome of P. insidiosum isolated from Sout...
Isolation and comparison of Arcanobacterium hippocoleae isolates from the genital tract of 15 mares. The present study reports the isolation of A. hippocoleae from genital swabs of 15 apparently healthy mares (at least one had an abortion one month earlier) and describes the genotypic and phenotypic characterisation of these strains. The mares were of eight different breeds with a thoroughbred dominance and came from 11 breeding farms located in the French region of Brittany. 16S rRNA gene sequencing confirmed the species' identification by comparing it with reference strain A. hippocoleae CIP 106850. Some degree of natural divergence within A. hippocoleae was observed by 16S rRNA sequencing ...
Structure and gene cluster of the O antigen of Escherichia coli F17, a candidate for a new O-serogroup. Escherichia coli F17 isolated from horse feces was studied in respect to the O antigen (O polysaccharide) structure and genetics. The lipopolysaccharide was isolated by phenol-water extraction of bacterial cells and cleaved by mild acid hydrolysis to yield the O polysaccharide, which was studied by sugar analysis and selective solvolysis with CFCOH along with one- and two-dimensional H and C NMR spectroscopy. The O polysaccharide was found to have a branched pentasaccharide repeat (O-unit) containing one residue each of d-galactose, d-mannose, l-rhamnose, d-glucuronic acid, and N-acetyl-d-gluc...
Denaturing Gradient Gel Electrophoresis Analysis of Bacteria in Italian Ticks and First Detection of Streptococcus equi in Rhipicephalus bursa from the Lazio Region. Tick-borne diseases are an increasing problem for the community. Ticks harbor a complex microbial population acquired while feeding on a variety of animals. Profiling the bacterial population by 16S rDNA amplification and denaturing gradient gel electrophoresis enables detection of the broad spectrum of bacteria that settles in the ticks. This study identified known and unknown tick-infecting bacteria in samples from Italy. Seven adult ticks from different hosts and origins were analyzed: two ticks from dogs (Lombardia), two ticks from bovines (Lazio), and three ticks from humans (Marche). ...
Diclazuril nonlinear mixed-effects pharmacokinetic modelling of plasma concentrations after oral administration to adult horses every 3-4 days. The purpose of this study was to determine if a low dose of diclazuril (0.5mg/kg of 1.56% diclazuril pellets) given to six healthy adult horses every 3-4 days for a total of five administrations would achieve steady-state plasma concentrations known to be inhibitory to Sarcocystis neurona and Neospora caninum. Blood was collected via venipuncture immediately before (trough concentrations) and 10h after (peak concentrations) each diclazuril administration and analysed by high-pressure liquid chromatography. The mean population-derived peak concentration was 0.284μg/mL and the mean terminal hal...
Antimicrobial susceptibility patterns of blood culture isolates from foals in Switzerland. We report blood culture results of 43 foals admitted to an equine hospital for medical or surgical disorders and determine minimal inhibitory concentrations (MIC) of different antibiotics. Eleven foals had a positive blood culture result despite prior administration of antibiotics in 10 of these animals. MIC values above EUCAST and/or CLSI breakpoints were identified in coagulase-negative staphylococci, methicillin-resistant Staphylococcus aureus (MRSA) and Enterococcus faecium. Gram-negative isolates were less frequently identified and did not appear to exhibit increased MIC values. This stud...
Dynamic changes in gene expression and signalling during trophoblast development in the horse. Equine chorionic girdle trophoblast cells play important endocrine and immune functions critical in supporting pregnancy. Very little is known about the genes and pathways that regulate chorionic girdle trophoblast development. Our aim was to identify genes and signalling pathways active in vivo in equine chorionic girdle trophoblast within a critical 7-days window. We exploited the late implantation of the equine conceptus to obtain trophoblast tissue. An Agilent equine 44K microarray was performed using RNA extracted from chorionic girdle and chorion (control) from equine pregnancy days 27, ...
Molecular analysis of the chromosomal 16S rRNA gene and vapA plasmid gene of Polish field strains of R. equi. Rhodococcus equi (R. hoagii) is an opportunistic pathogen commonly found in foals up to 6 months old and animal environment. The R. equi genome contains genetically stable chromosomal DNA and an 80-90 kb plasmid containing vapA gene, responsible for virulence. Most reports from around the world focus on the determination of R. equi plasmid profiles. Few studies have attempted to determine differences in nucleotide sequences between virulent strains of R. equi isolated from foals and breeding environment. The aim of the study was to perform a molecular analysis of a fragment of the chromosomal ...
Actinomyces denticolens as a causative agent of actinomycosis in animals. The name "Actinomyces suis" was applied to each actinomycete isolate from swine actinomycosis by Grässer in 1962 and Franke in 1973. Nevertheless, this specific species was not included in the "Approved List of Bacterial Name" due to absence of the type cultures. Therefore, "Actinomyces suis" based on the description of Franke 1973 has been considered as "species incertae sedis". We isolated a number of Actinomyces strains from swine. The representative strains of them was designated as Chiba 101 that was closely similar to the description in "Actinomyces suis" reported by Franke in 1973. Int...
In silico identification of immunodominant B-cell and T-cell epitopes of non-structural proteins of Usutu Virus. Usutu Virus (USUV; flavivirus) is a re-emerging pathogen invading the territories of European countries, Asia, and Africa. It is a mosquito-borne zoonotic virus with a bi-directional transmission route from animal to human and vice versa, and causes neurological disorders such as meningoencephalitis in bats, Homo sapiens, birds and horses. Due to limited availability of information about USUV and its deleterious effects on neural cells causing neurologic impairments, it becomes imperative to study this virus in detail to equip ourselves with a solution beforehand. The current study aims to ide...
Transcriptome analysis of immune genes in peripheral blood mononuclear cells of young foals and adult horses. During the neonatal period, the ability to generate immune effector and memory responses to vaccines or pathogens is often questioned. This study was undertaken to obtain a global view of the natural differences in the expression of immune genes early in life. Our hypothesis was that transcriptome analyses of peripheral blood mononuclear cells (PBMCs) of foals (on day 1 and day 42 after birth) and adult horses would show differential gene expression profiles that characterize natural immune processes. Gene ontology enrichment analysis provided assessment of biological processes affected by age...
Some aspects on tick species in Mongolia and their potential role in the transmission of equine piroplasms, Anaplasma phagocytophilum and Borrelia burgdorferi L. Ticks are cosmopolitan vectors of numerous diseases, and detection of various pathogens in ticks can help to assess their distribution. In the current study, 528 adult ticks were collected from grazing animals or the ground in ten different Mongolian provinces. Dermacentor nuttalli constituted 76.1% of them and was found in all ecozones except the eastern desert. Dermacentor marginatus (8.3%), Dermacentor silvarum (1.1%) and Ixodes persulcatus (3.0%) were found in the northern forest areas and Hyalomma asiaticum (11.4%) only in the southern (semi-)desert. Of these, 359 ticks were subjected to ...
Comparative seroprevalence and risk factor analysis of Trypanosoma evansi infection in equines from different agro-climatic zones of Punjab (India). As parasitaemia is low and fluctuating during the chronic stage of infection, accurate detection of Trypanosoma evansi in blood is difficult. The primary aims of this investigation were to assess for the first time the seroprevalence of T. evansi in all agro-climatic zones of Punjab, by indirect enzyme-linked immunosorbent assay (iELISA) and card agglutination test (CATT/T. evansi), and to evaluate the risk factors associated with latent trypanosomosis. A total of 319 equine serum samples collected from 12 districts of Punjab (India) belonging to different agro-climatic zones revealed 39 (12.2...