Topic:Contagious Equine Metritis
Contagious Equine Metritis (CEM) is a venereal disease in horses caused by the bacterium Taylorella equigenitalis. It primarily affects the reproductive tract of mares, leading to inflammation and potentially impacting fertility. Stallions can carry the bacterium asymptomatically, acting as vectors for transmission during breeding. Diagnosis of CEM involves bacterial culture, polymerase chain reaction (PCR) testing, and serological assays. Control measures include quarantine, testing, and treatment of infected animals. This page compiles peer-reviewed research studies and scholarly articles that investigate the epidemiology, pathogenesis, diagnostic methods, and management strategies for Contagious Equine Metritis in equine populations.
Antimicrobial resistance and genetic diversity of Klebsiella pneumoniae strains from different clinical sources in horses. Klebsiella pneumoniae is a major cause of infections and reproductive disorders among horses, ranked in recent French studies as the sixth most frequently isolated bacterial pathogen in equine clinical samples. The proportion of multidrug-resistant (MDR) K. pneumoniae is therefore significant in a context where MDR K. pneumoniae strains are considered a major global concern by the World Health Organization. Unassigned: In this study, we used a genomic approach to characterize a population of 119 equine K. pneumoniae strains collected by two laboratories specialized in animal health in Normandy...
Core genome multilocus sequence typing analysis of Finnish Taylorella equigenitalis isolates. In Finland, Taylorella equigenitalis, the causative agent of contagious equine metritis (CEM), was first detected in 1992. The aim of this study was to genotype Finnish T. equigenitalis isolates to investigate the epidemiology of the infection in the Finnish horse population. A total of 34 T. equigenitalis isolates from 24 horses obtained during 1992-2021 were subjected to whole genome sequencing (WGS) and subsequent local ad hoc core genome multi-locus sequence typing (cgMLST) targeting 1259 loci. Classical MLST profiles were extracted from the whole-genome sequence data. Three novel MLST ty...
Enhanced detection of Taylorella equigenitalis by qPCR using ‘Dry’ swabs. Detection of Taylorella equigenitalis (CEMO) in the horse uses genital swabs. These swabs traditionally have been put in Amies charcoal transport medium for detection by culture but are also used for PCR. We determined the suitability of swabs without transport medium (Dry swabs) for CEMO PCR compared to swabs in Amies charcoal transport medium. The experiment was a factorial design using swab type and dilution of organism in culture suspensions, done in two parts. Simulated genital swabs were prepared in the laboratory by dipping in pairs into culture suspensions containing T. equigenitalis w...
Surveillance of Contagious Equine Metritis: Results of the First 5-Year Period of French Proficiency Tests for Taylorella equigenitalis Detection by Real-Time PCR. Contagious equine metritis (CEM) detection by PCR is recognized by the European Union according to Commission Implementing Regulation (EU) No 846/2014, and real-time PCR is now recommended by the World Organisation for Animal Health Terrestrial Manual at the same level as the culture method. The present study highlights the creation of an efficient network of approved laboratories in France in 2017 for CEM detection by real-time PCR. The network currently consists of 20 laboratories. A first proficiency test (PT) was organized by the national reference laboratory for CEM in 2017 to evaluate th...
First report and molecular characterization of cases of natural Taylorella asinigenitalis infection in three donkey breeds in Spain. Taylorella asinigenitalis is a non-pathogenic bacteria isolated from the genital tract of donkeys but also a cause of metritis and vaginal discharge in mares. It is closely related to Taylorella equigenitalis, the cause of Contagious Equine Metritis (CEM) in horses, and has been present in different countries in Europe since 1995. Up to date, there are no studies on the prevalence of T. asinigenitalis in the equine or asinine populations in Spain; this is the first report of the presence of T. asinigenitalis in donkeys (Equus asinus) from different breeds in three regions of Spain. A total of ...
Screening for Taylorella equigenitalis in Equine Semen: An Exploratory Study. The study examined and compared the sensitivity of culture and a quantitative PCR assay for screening equine semen for the presence of Taylorella equigenitalis (CEMO). Chilled semen samples, both raw and treated with extender, from two stallions were spiked with the organism at seven or 23 days postejaculation and prepared in serial dilutions. Culture of the 7-day raw semen readily detected CEMO at all dilutions, but extended semen yielded counts that were two log cycles lower at equivalent dilutions, with the organism being nearly undetectable at the maximal dilutions. By contrast, PCR sensit...
Taylorella asinigenitalis: raising awareness of its importance and presence in equine and asinine populations. Taylorella equigenitalis has long been recognised as a causative agent of contagious equine metritis, but practitioners may be less familiar with Taylorella asinigenitalis, which has been identified more recently. Here, Abel Dorrego, Consuelo Serres and Fatima Cruz-Lopez of the Universidad Complutense de Madrid describe T asinigenitalis and report the findings of a survey they carried out in donkeys in Spain.
Comparison of five basal compositions of selective chocolate agar media for isolation of Taylorella equigenitalis. The gold standard method to isolate and identify Taylorella equigenitalis, the contagious agent of equine metritis, is the culture method according to the World Organisation for Animal Health Terrestrial Manual. No selective T. equigenitalis chocolate agar medium has been developed since the 1980s and the existing media show limited performances due to the fastidious nature of T. equigenitalis and the presence of interfering bacteria in the genital tract of equines. Here, the growth rates of 6 T. equigenitalis strains and 7 non-T. equigenitalis strains were compared on Timoney's selective medi...
Comparison of seven nucleic acid amplification tests for detection of Taylorella equigenitalis. Taylorella equigenitalis causes contagious equine metritis. Here we compared seven nucleic acid amplification tests for T. equigenitalis to select a rapid and reliable diagnostic method. The 95% detection limits of each assay varied greatly: real-time PCR had the lowest detection limit (0.77 fg/reaction); those of some of the conventional PCRs (cPCRs) were >100 fg/reaction. In experimentally infected samples, real-time PCR and semi-nested PCR showed the highest positive numbers (33 out of 42 samples), but two of the cPCRs detected only 2 and 7 positive results. Our results indicate that the us...
Preservation of viable Taylorella equigenitalis in different commercially available transport systems. The cultural diagnosis of the causal agent of contagious equine metritis (Taylorella equigenitalis) using transport swabs is challenging. Swabs must be placed in Amies charcoal medium, refrigerated during transport, and plated out at the laboratory no later than 48 h after sampling. In this study, the viability of T. equigenitalis strain CIP 79.7T in 11 commercial swab transport systems was initially compared at 1 day and 2 days of storage at ambient (20 ± 3 °C) or refrigerated (5 ± 3 °C) temperature. The four best swab transport systems, systems B, E, F (used as the reference) and K, were...
Validation of an Easy Handling Sample Preparation and Triplex Real Time PCR for Rapid Detection of T. equigenitalis and Other Organisms Associated with Endometritis in Mares. Isolation and identification of Taylorella equigenitalis, the causative agent of contagious equine metritis, by bacteriology is laborious and does not permit differentiation from the other member of the genus, Taylorella asinigenitalis. Moreover, other organisms such as Klebsiella pneumoniae and Pseudomonas aeruginosa can also cause endometritis in mares and warrant diagnostic detection. Our objectives were to develop a rapid preparation method for field swab samples and to validate this protocol using new multiplex real-time polymerase chain reaction (rtPCR) detection tools for identification...
Comparative Semen Microbiota Composition of a Stallion in a Taylorella equigenitalis Carrier and Non-Carrier State. Contagious equine metritis is receiving renewed attention due to the continuous detection of carriers in apparent agent-free farms. Interactions of Taylorella with the seminal microflora may be the plausible cause behind these spontaneous changes of the carrier state. Accordingly, the aim of this study was to compare the differences in the seminal microbiome composition of one stallion in the contagious equine metritis carrier state and non-carrier state. Samples were cryopreserved after their extraction. Cell disruption was performed by high-speed homogenization in grinding media. Bacterial f...
Overview of spatio-temporal distribution inferred by multi-locus sequence typing of Taylorella equigenitalis isolated worldwide from 1977 to 2018 in equidae. The accurate identification of Taylorella equigenitalis strains is essential to improve worldwide prevention and control strategies for contagious equine metritis (CEM). This study compared 367 worldwide equine strains using multilocus sequence typing according to the geographical origin, isolation year and equine breed. The strains were divided into 49 sequence types (STs), including 10 described for the first time. Three major and three minor clonal complexes (CCs), and 11 singletons, were identified. The genetic heterogeneity was low (0.13 STs/strain) despite the wide diversity of geographi...
Ten years of Taylorella equigenitalis ring trial results comparing culture and polymerase chain reaction. Taylorella equigenitalis, the cause of contagious equine metritis (CEM), can be detected by culture but in recent years polymerase chain reaction (PCR) has also been used. In 2008, the World Organisation for Animal Health (OIE) Reference Laboratory for CEM in the United Kingdom set up a ring trial for laboratories to assess their ability to identify T. equigenitalis in laboratory-prepared samples because the identification of T. equigenitalis in the laboratory was recognised to be difficult. Freeze-dried culture suspensions in various combinations of any of T. equigenitalis, Taylorella asinige...
Direct culture-independent sequence typing of Taylorella equigenitalis obtained from genital swabs and frozen semen samples from South African horses. We report herein the use of crude extracts obtained from samples of Taylorella equigenitalis-infected horses for the purpose of multi-locus sequence typing (MLST). Samples (n = 36) were collected from horses in South Africa from 1996 to 2017: 34 from genital swabs (stored at -20°C for 2-3 y) and 2 from cryopreserved raw semen aliquots (stored at -70°C for 18 y) prior to assay. The MLST assay showed a single sequence type (ST), designated ST4, that supported a point introduction and thus a common source for the South African outbreak of contagious equine metritis.
Acute Endometritis due to Taylorella equigenitalis Transmission by Insemination of Cryopreserved Stallion Semen. Taylorella equigenitalis can be transmitted during artificial insemination. This report describes clinical T. equigenitalis transmission by cryopreserved stallion semen. T. equigenitalis isolates from a mare's vaginal discharge and semen from the same batch of the cryopreserved semen used for the insemination gave identical API ZYM, antibiotic susceptibility, and multilocus sequence typing results (ST-46); furthermore, the multilocus sequence typing lineage ST-46 is known to circulate in the country of semen collection. These results support the need for strict contagious equine metritis scre...
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 ...
Draft Genome Sequence of Taylorella equigenitalis Strain 210217RC10635, Isolated from a Pony Stallion in Germany. Here, we report the draft genome sequence of Taylorella equigenitalis strain 210217RC10635, a Gram-negative bacterium belonging to the genus Taylorella and the order Burkholderiales. Taylorella equigenitalis is the causative agent of contagious equine metritis (CEM). The strain reported here was isolated in 2017 from a German stallion.
Pooling of genital swabs for detection by PCR of Taylorella equigenitalis, the cause of contagious equine metritis. Sets of genital swabs are routinely taken from horses to screen for the presence of Taylorella equigenitalis, the cause of contagious equine metritis. Typically, two to four different sites are swabbed at a time and tested by culture or PCR. Objective: This study explored the feasibility of pooling these swabs for a single PCR test per animal instead of testing each swab individually. Methods: In vitro. Methods: PCR signal strengths (Ct values) from 149 historical PCR positive genital swabs, together with historical data on the number of swabs in a set expected to be positive, were used to ass...
Frequency of shedding of respiratory pathogens in horses recently imported to the United States. Imported horses that have undergone recent long distance transport might represent a serious risk for spreading infectious respiratory pathogens into populations of horses. Objective: To investigate the frequency of shedding of respiratory pathogens in recently imported horses. Methods: All imported horses with signed owner consent (n = 167) entering a USDA quarantine for contagious equine metritis from October 2014 to June 2016 were enrolled in the study. Methods: Prospective observational study. Enrolled horses had a physical examination performed and nasal secretions collected at the ti...
Towards European harmonisation of contagious equine metritis diagnosis through interlaboratory trials. The performance of culture and PCR methods routinely used to diagnose contagious equine metritis (CEM) was evaluated and compared by two interlaboratory trials involving a total of 24 European laboratories, including 22 National Reference Laboratories for CEM. Samples were swab specimens artificially contaminated with bacteria present in the genital tract of Equidae, some with and some without Taylorella equigenitalis, the causative agent of CEM, and T asinigenitalis, responsible for possible misidentification as T equigenitalis Throughout both interlaboratory trials, PCR performed better in t...
Genomic diversity of Taylorella equigenitalis introduced into the United States from 1978 to 2012. Contagious equine metritis is a disease of worldwide concern in equids. The United States is considered to be free of the disease although sporadic outbreaks have occurred over the last few decades that were thought to be associated with the importation of horses. The objective of this study was to create finished, reference quality genomes that characterize the diversity of Taylorella equigenitalis isolates introduced into the USA, and identify their differences. Five isolates of T. equigenitalis associated with introductions into the USA from unique sources were sequenced using both short an...
Half a century of equine reproduction research and application: A veterinary tour de force. Over the past 50 years, per season pregnancy rate in Thoroughbred mares have risen from 70 to >90% and foaling rates from 55 to >80%. Some of the significant pharmacological treatments and diagnostic methods which have driven this marked improvement in breeding efficiency are reviewed. They include the application of artificial lighting to hasten the onset of ovulatory oestrous cyclicity in early Spring, rapid steroid hormone assays to aid in determining the stage and normality of the mare's cycle, prostaglandin analogues, synthetic progestagens and Gonadotrophin-releasing Hormone (GnRH) anal...
Contagious equine metritis in Portugal: A retrospective report of the first outbreak in the country and recent contagious equine metritis test results. Contagious equine metritis (CEM), a highly contagious bacterial venereal infection of equids, caused by Taylorella equigenitalis, is of major international concern, causing short-term infertility in mares. Portugal has a long tradition of horse breeding and exportation and until recently was considered CEM-free. However, in 2008, T. equigenitalis was isolated at our laboratory from a recently imported stallion and 2 mares from the same stud. Following this first reported outbreak, the Portuguese Veterinary Authority (DGVA) performed mandatory testing on all remaining equines at the stud (n=30)...
Draft Genome Sequence of Taylorella equigenitalis Strain ERC_G2224 Isolated from the Semen of a Lipizzaner Stallion in South Africa. Taylorella equigenitalis is the causative agent of contagious equine metritis (CEM), a sexually transmitted infection of horses. We report here the genome sequence of T. equigenitalis strain ERC_G2224, isolated in 2015 from a semen sample collected in 1996 from a Lipizzaner stallion in South Africa.