Microbiology and horses explores the interactions between microorganisms and equine hosts, focusing on the role of bacteria, viruses, fungi, and other microbes in horse health and disease. This field examines the microbial flora present in various equine environments, including the gastrointestinal tract, skin, and respiratory system, and investigates how these microorganisms influence equine physiology and pathology. Research in this area includes studies on microbial infections that affect horses, the development of antimicrobial resistance, and the impact of probiotics and prebiotics on equine health. This page compiles peer-reviewed research studies and scholarly articles that investigate the diversity, dynamics, and implications of microbial communities in horses, as well as the strategies for managing microbial-related diseases.
Motta D, Aymée L, Roussouliéres I, Di Azevedo MIN, Jacob JCF, Lilenbaum W.Leptospirosis is a zoonotic disease caused by spirochetes of the genus Leptospira. Equine genital leptospirosis (EGL) has been described as a chronic and silent syndrome, presenting reproductive alterations such as abortion, stillbirth, placentitis, embryonic loss, repeat breeding syndrome, and subfertility. This study aimed to investigate the genital Leptospira infection in naturally infected mares with poor reproductive performance, as well as to genetically characterize the agents. A total of 41 mares with a history of poor reproductive performance were selected. Sera were collected for ser...
Uprety T, Shaffer CL, Loynachan A, Janes J, Cassone L, Kennedy L, Bryant U, Ruby R, Swan M, Sponseller BT, Adam E, Lubbers B, Erol E.Salmonellosis is a highly contagious, zoonotic disease affecting both animal and human health. Early characterization of emerging Salmonella serotypes and associated antimicrobial resistance patterns are essential for outbreak controls in animals and humans. Between 2018 and 2025, 245 Salmonella enterica subsp. enterica were isolated from both ante-mortem and post-mortem equine cases. The predominant Salmonella serotypes were Typhimurium (83), Newport (28), 1,4,[5],12:i:- (26), Saintpaul (25), Hartford (15), and Mbandaka (12). S. Saintpaul, previously rare in horses, was detected in 21 cases i...
Uzal FA, Navarro MA, Asin J, Henderson E.Clostridioides difficile affects humans, and several other animal species, such as horses, pigs, gerbils, guinea pigs, hamsters, and rabbits. This microorganism has also been isolated from the gastrointestinal tract of healthy individuals of a wide variety of animal species in which its association with disease is not known. Traditionally, in most domestic animal species, C. difficile-infection disease (CDI) was antibiotic-associated, although in the past few years more cases in which no antibiotic association was known have been described. In addition, no antibiotic association has been descr...
Junkkari R, Mykkänen A, Sulku P, Rantala M, Pohjanvirta T, Eklund M, Pelkonen S, Grönthal T. subsp. (), an opportunistic pathogen often found in the stable environment and upper respiratory tract of young horses, can cause severe pneumonias in Equidae. In this study we investigated the occurrence, genetic variation and antimicrobial susceptibility of isolates from 63 weanling horses kept in loose housing or conventional stables. The bacterial isolates were typed by using pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST). The possible associating factors (stable type, age, breed and clinical signs) for positive finding were analysed using logistic regre...
Stöckle SD, Kannapin DA, Merle R, Lübke-Becker A, Gehlen H. The emergence and spread of multi-drug-resistant (MDR) bacteria pose a growing threat in veterinary medicine, particularly in equine hospitals. This study investigated the colonization and infection dynamics of horses undergoing emergency laparotomy with two distinct antibiotic protocols (single-shot versus 5-day protocol) during hospitalization. Nasal swabs and fecal samples were collected from 67 horses undergoing emergency laparotomy at clinic admission as well as on postoperative days 3 and 10. These were screened for multi-drug-resistant indicator pathogens. As multi-drug-resistant indi...
Salinas P, Vergara MA, Tapia D.Navicular syndrome (NS) is a chronic, degenerative condition of the equine thoracic limb that compromises the distal sesamoid bone (DSB) and associated structures responsible for stabilization and load absorption during locomotion. Although historically attributed to vascular alterations, its etiology is now recognized as biomechanical, characterized by chronic overload of the deep digital flexor tendon. Conventional diagnostic techniques-radiography, scintigraphy, and ultrasonography-lack the sensitivity and precision required to detect early microarchitectural alterations. This study aimed t...
Stolle LM, Oltmanns H, Meißner J, Heun F, Schieder AK, Wolff HT, Ohnesorge B, Busse C.To determine the in vitro antimicrobial activity of specific antiseptics against common equine ocular surface pathogens. Methods: Staphylococcus aureus (S. aureus) (n = 12), Streptococcus equi subspecies zooepidemicus (S. zooepidemicus) (n = 9), Enterobacter hormaechei (E. hormaechei) (n = 6), and Bacillus cereus (B. cereus) (n = 5) were collected from corneal samples of horses with ulcerative keratitis. Reference strains were included. Minimum bactericidal concentrations (MBC) of polyhexanide, povidone-iodine, and hypochlorous acid were tested using the microdilution method. ...
Ganbaatar O, Batbaatar V, Kimura T, Ganzorig S, Tseren-Ochir EO, Suzuki Y, Takai S.ELISA antibody titers against Rhodococcus equi strain ATCC 6939 were measured in serum samples collected from 644 horses aged 1-21 years at 13 provinces and the capital of Mongolia, of which 631 (98%) samples showed values of approximately zero. The mean antibody titers in the 14 areas ranged from -0.08 to -0.01. Nine samples (1.4%) exhibited titers of 0.1-0.2, and surprisingly, four horses (0.6%) each aged 2, 5, 8, and 9 years demonstrated positive values in the range of 0.3-0.8. Considering the age resistance characteristic of this disease, the positive horses were hypothesized to exhibit no...
Khalil WA, Sharf MI, Derbala MK, Hassan MAE, Abdelnour SA, El-Harairy MA.This study aims to investigate the cryoprotective effect of Omega-3 nano-emulsion (Omega-3 NE) on stallion sperm quality, kinematic parameters, acrosome status, subcellular ultrastructure, oxidative/antioxidant markers, and semen microbiota. Forty ejaculates were collected, extended, and cryopreserved from 5 fertile Pure Egyptian stallions (Equus caballus). The ejaculates were divided into five groups: a control group (without additive) and four groups supplemented with 25, 50, 100, and 200 μg of Omega-3 NE/mL. The Omega-3 NE exhibited an average particle size of 51-146 nm, a PDI of 0.58,...
Franzan BC, da Silva Coelho I, Ramos EM, de Souza ARP, de Almeida FQ, Silva VP.This study aimed to investigate the gradual adaptation of the fecal bacterial community and in vitro fermentative capacity of horses fed a complete extruded diet (CED). Twelve geldings weighing 370 kg were removed from a native pasture and fed coastcross hay (Cynodon spp) for 7 days. In the second week, horses were assigned to two groups: one group was fed exclusively with coastcross hay (HAY) for 28 days and the other group fed with weekly increases of CED (30%, 60%, and 100%) to replace HAY. Fecal samples were collected on Days 7, 14, 21, and 28 for microbiota and in vitro fermentati...
Dersch K, Kreuder A, Wang C, Troy J.Surgical site infections (SSI) are a common postoperative complication of equine orthopedic surgery and often increase morbidity and mortality. Objective: This study aimed to determine if covering surgical instruments during surgery decreased bacterial environmental air contamination during early opening of surgical packs (EOSP). The authors hypothesized that covering instruments with sterile surgical towels would reduce the total number of bacterial colonies to which the instruments were exposed. Methods: Blood agar plates (BAP) were allocated into two groups (non-covered vs. covered with a s...
Liu J, Huang X, Wang Y, Wang Y, Luo R, Lu X, Cao K, Xing J, Tu Y, Zheng W.Antibiotic resistance genes (ARGs) are emerging contaminants threatening public health, yet their transmission risk via mare milk products remains understudied. Using metagenomics, we analyzed lactic acid bacteria (LAB)-inoculated fermented, naturally fermented, raw, and pasteurized mare milk to investigate the effect of LAB inoculation on the distribution and transmission pathways of ARGs in mare milk. The results showed that naturally fermented, raw, and pasteurized mare milk had the highest number of pathogens, relative abundance of ARGs, and relative abundance of mobile genetic elements (M...
To date, there is extensive scientific evidence affirming that physical exercise plays a fundamental role in both the prevention and treatment of various pathological conditions in humans as well as in animals. It is understood that the advantages of movement and exercise have a multifactorial origin and they depend on a category of bioactive molecules vehicolated by extracellular microvesicles known as exosomes. The exosomes act as potential delivery systems for messages within the organism. These findings have drawn significant attention, leading researchers to further investigate the role o...
He H, Han L, Ni W, Yu J, Liu K, Li W, Li C, Hu S, Li C, Li X.Herbivores represent crucial subjects for mining highly efficient carbohydrate-active enzymes (CAZymes) from gut microbiomes. Here, we analyzed 12,763 metagenome-assembled genomes (MAGs) from the horse gut, revealing that its microbial community as a rich reservoir of CAZymes diversity, with 5,204,848 glycoside hydrolases (GHs) and 4,596,191 glycosyl transferases (GTs) identified. Our findings demonstrate that Bacteroidota (5,479,287 CAZymes) and Bacillota_A (2,987,684 CAZymes) serve as the primary functional phyla for plant polysaccharide degradation. A total of 17,250 polysaccharide utilizat...
Petry S, Tapprest J, Maillard K, Barbut F, Duquesne F, Kozak S, Foucher N, Bernez-Romand M, Bridoux L, Poquet I. an anaerobic, spore-forming enteropathogen, is less studied in animals than in humans despite its importance in One Health. We evaluated occurrence, diversity, circulation, and virulence in French Equidae ( = 100) after their necropsy in northwestern France, from 2019 to 2021. We systematically recovered all cecal contents and any watery intestinal contents. We isolated strains, determined their toxin gene profile by PCR, and established their PCR-ribotype according to the WEBRIBO database. We also performed free toxin detection. Twenty-seven Equidae were positive for and 20 had a toxigeni...
Friedlund AM, Bracamonte JL, Koziy RV, Epp T, Thomas KL.To evaluate if high-volume lavage results in a negative bacterial culture of egress fluid, regardless of pathogen in an experimental model of equine septic arthritis. Methods: Experimental study. Methods: A total of 11 horses in three groups (lipopolysaccharide [LPS] Group 1, n = 4; Escherichia coli [E. coli] Group 2, n = 4; Staphylococcus aureus [S. aureus] Group 3, n = 3). Methods: A middle carpal joint of each horse was injected with LPS (synovitis Group 1), E. coli (septic arthritis Group 2) or S. aureus (septic arthritis Group 3). Arthroscopic lavage of the middle carpal joint...
Zhang Y, Zhang M, Zhao Z, Peng Y, Deng F, Jiang H, Zhang M, Song B, Kim JK, Pan JH, Chai J, Li Y.Unique skin microbial communities have been shaped by the harsh climatic conditions in high-altitude areas, such as intense ultraviolet radiation and low oxygen concentration. However, it is unknown whether high altitude contributes to shaping common microbiota inhabiting the skin across different mammals. The skin microbial communities of humans and horses living in high-altitude (Tibetan) and low-altitude areas were analyzed using full-length 16S rRNA sequencing technology. Alpha diversity differed between high- and low-altitude groups ( < 0.01). Skin microbial community composition also dif...
Strompfová V, Štempelová L, Bujňáková D, Karahutová L, Gondoľová D, Nagyová M, Siegfried L.In order to develop non-antibiotic therapies to treat dermatological diseases it is urgent to spread knowledge on composition and properties of skin bacteria in healthy animals. Since horses are popular companions of humans, it is necessary to know what risk skin bacteria pose to humans. Therefore the aim of this work was to analyse species composition of staphylococci isolated from skin swabs of 50 healthy horses using MALDI-TOF (Matrix-Assisted Laser Desorption/Ionization Time-of-Flight) spectrometry and to characterize their virulence properties. Swabs were collected from five body areas (n...
Wei L, Wei J, Liu X, Chen W, Wang C, Khan MZ, Zhang Z.Donkeys () remain nutritionally understudied despite their critical roles in agriculture across developing regions, with current feeding practices inappropriately extrapolating horse standards without accounting for species-specific digestive physiology. No comprehensive synthesis has integrated how dietary modifications systematically alter gut microbial communities to drive measurable health outcomes in donkeys, preventing development of evidence-based feeding strategies. This review critically synthesizes current evidence on donkey nutritional requirements and gut microbiota dynamics to est...
Wang C, Wang J, Ma B, Liu T, Yuan X, Meng J, Zeng Y.: This study investigated the effects of dietary bamboo leaf extract (BLE) on milk parameters and intestinal microbiota in lactating mares. : Twenty-four mares of similar age (10 ± 2 years), weight (360.62 ± 15.23 kg) and body condition were selected for this study and randomly divided into four groups of six mares each: an untreated control group (CG) and three experimental groups (EG1, EG2, EG3) were fed a basal diet supplemented with 0, 10, 20, or 30 g/day of BLE, respectively, for 60 days. Then, horse milk composition, antioxidant activity, and immunoglobulin levels along with the rela...
Verwilghen DR, Pelosi A, Abbas M, Allerton F, Archer D, Baxter G, Brehm W, Burgess BA, Dallap-Schaer B, Ferreira J, Isgren C, Harbarth S, Jacobsen S....To establish specific veterinary surgical site infection (SSI) terminology to support the creation of consistent, comparable, and repeatable clinical and research datasets. Unassigned: Establishment of SSI definitions by iterative Delphi questionnaires leading to a convergence of consensus opinion by a multidisciplinary panel of 32 specialists in large- and small-animal surgery (European College of Veterinary Surgeons, American College of Veterinary Surgeons), veterinary internal medicine (American College of Veterinary Internal Medicine, European College of Veterinary Internal Medicine, Europ...
Parker M, Arnade H, Parker JL, Gordon J, Peroni JF.Investigation of alternative antibiotic therapies is critical for the future of medicine. Platelet lysate (PL) is a blood product that has shown antibiotic potential, which could be used to augment or replace current antibiotics. Objective: To compare the effects of equine PL versus antibiotics on growth of clinically isolated antibiotic resistant bacteria. We hypothesized that PL would exert an antimicrobial effect on equine bacterial isolates resistant to antibiotics. Methods: In vitro experimental study. Platelets were collected via apheresis from nine donor horses and underwent two freeze-...
Bazan L, Argibay HD, Borges-Silva W, Pita Gondim LF, Dos Santos Mattos TA, Santana JO, da Silva EM, Begon M, Khalil H, Costa F, de Oliveira Carneiro I.Toxoplasma gondii is a globally neglected zoonotic parasite, particularly prevalent in socioeconomically vulnerable areas. Various animal species serve as reservoirs for T. gondii across different regions, including domestic cats, livestock, and a variety of wild and synanthropic animals. In urban areas, especially informal settlements, the close coexistence of humans, domestic animals, and wildlife may influence local transmission dynamics. This study evaluated the seroprevalence and associated risk factors for T. gondii infection in domestic and synanthropic animals from two low-income neigh...
Hoerdemann M, Sahoo DK, Allbaugh RA, Kubai MA.To assess if an inexpensive, commercially available ultraviolet C (UV-C) light device with a peak emission of 275 nm can inhibit equine keratomycosis-associated pathogens located at different corneal depths in an ex vivo model. Methods: A controlled, randomized experimental design. Aspergillus fumigatus and Fusarium solani isolates were inoculated in fresh bovine corneoscleral transplants, superficially or at 450 μm of stromal depth for the ulcerative keratomycosis or stromal abscess model, respectively. After a minimum of 18 h of incubation, treatment groups received 15 s of UV-C li...
Singh B, Sulaiman ZI, Raynor EM.We present a rare case of subspecies zooepidemicus (SEZ) bacteremia in a 73-year-old male with a history of Parkinson's disease, pulmonary embolism, and recent left knee total arthroplasty who developed fever and sepsis complicated by septic arthritis of a prosthetic knee and deep vein thrombosis (DVT). Blood cultures grew in four out of four bottles, and history revealed frequent horse exposure, suggesting zoonotic transmission with hematogenous seeding of the prosthetic joint. The diagnosis was further challenged by systemic computed tomography (CT) abnormalities and the concurrent DVT, wh...
Gao W, Liu M, Nurdaly K, Caidan D, Sun Y, Duan J, Zhao J, Gong X, Zhou J, Zhang Y, Chen Q.Equine bacterial abortion presents substantial economic and One Health challenges; however, comprehensive epidemiological data from China are limited. This study sought to ascertain the overall prevalence of key pathogens-namely, spp., , , and spp.-in equine populations in northwestern China. In this study, we aimed to further elucidate the characteristics of co-infections, profile antimicrobial resistance genes, and identify associated risk factors. Conducted as a cross-sectional analysis across four provinces, we collected 508 blood samples and 24 abortion tissue samples from 15 farms. Pat...
Southwood LL, Long A, Perez J, Daniel S, Bittinger K, Aitken M, Redding L.Based on human studies, surgical antimicrobial (AMD) prophylaxis (SAP) beyond 24 h is unnecessary and potentially detrimental. Objective: To compare clinical and microbiological outcomes in patients receiving 24- or 72-h of SAP for colic surgery. Methods: Prospective randomised clinical trial. Methods: Horses that recovered from colic surgery were considered. Exclusion criteria were (1) age <2 years; (2) Miniature Horses, pony, and draught breeds; (3) azotaemia; (4) recent hospitalisation, colic surgery, or AMDs; (5) local AMD administration. Eligible horses were randomly assigned to recei...
Rudeekiatthamrong A, Nguyen GT, Kamyingkird K. infection (Surra) remains a major constraint to equine health and productivity in Thailand. The only available trypanocidal drug, diminazene aceturate (DA), has limited efficacy, poor blood-brain barrier penetration, and toxicity in horses. This study aimed to investigate the inhibitory effects of commonly used equine antibiotics, gentamicin (GMC), ceftiofur (CTF), and trimethoprim-sulfamethoxazole (TS), against (Thai strain isolated from dairy cattle number 953; TEDC 953) to identify potential therapeutic alternatives or adjuncts for equine trypanosomosis. Unassigned: An growth inhibition...
Nowicka B, Łopuszyński W, Krajewska-Wędzina M, Biazik A, Sobuś M, Polkowska I, Szacawa E.Gastrointestinal mycobacteriosis in horses is difficult to diagnose because of the pathogen's intracellular nature and the non-specific clinical symptoms. Effective accurate diagnosis facilitates prognosis and treatment. Current diagnostic procedures and methods of collecting material do not permit definitive antemortem diagnosis. However, culturing, acid-fast bacilli staining, histopathology, PCR and immunological marker evaluation may prove useful. Unassigned: Three horses were admitted to a clinic for intensive care and a final diagnosis. Physical examination and additional tests were perfo...
Silva JG, Martins KR, Rahal NM, Schuch LFD, Cunha RC, Meireles MCA.Neorickettsia risticii, an obligate intracellular bacterium, is the causative agent of Potomac Horse Fever (PHF) - a systemic, acute, and potentially fatal diarrheal disease. This pathogen is an endosymbiont of digenetic trematodes, with freshwater snails playing a role in its biological cycle. The disease exhibits endemic and seasonal patterns, primarily affecting horses in wetlands during warmer months, and has been documented in the United States, Canada, Europe, and South America. Previous studies confirmed the pathogen's presence in herds from southern Brazil via serology and PCR; however...
Ewers C, Stamm I, Pfeifer Y, Wieler LH, Kopp PA, Schønning K, Prenger-Berninghoff E, Scheufen S, Stolle I, Günther S, Bethe A.To investigate the clinical relevance and molecular epidemiology of extended-spectrum β-lactamase (ESBL)-producing Klebsiella species in animals. Methods: Antimicrobial susceptibilities and presence of ESBLs were examined among Klebsiella spp. (n = 1519) from clinical samples (>1200 senders from Germany and other European countries) mainly from companion animals and horses from October 2008 to March 2010. Multilocus sequence typing (MLST) and PFGE were performed including human isolates for comparative purposes. Results: The overall ESBL rate was 8% for Klebsiella pneumoniae subsp. pne...
O' Donnell MM, Harris HM, Jeffery IB, Claesson MJ, Younge B, O' Toole PW, Ross RP.In this study, we characterized the gut microbiota in six healthy Irish thoroughbred racehorses and showed it to be dominated by the phyla Firmicutes, Bacteroidetes, Proteobacteria, Verrucomicrobia, Actinobacteria, Euryarchaeota, Fibrobacteres and Spirochaetes. Moreover, all the horses harboured Clostridium, Fibrobacter, Faecalibacterium, Ruminococcus, Eubacterium, Oscillospira, Blautia Anaerotruncus, Coprococcus, Treponema and Lactobacillus spp. Notwithstanding the sample size, it was noteworthy that the core microbiota species assignments identified Fibrobacter succinogenes, Eubacterium copr...
McNulty SN, Tort JF, Rinaldi G, Fischer K, Rosa BA, Smircich P, Fontenla S, Choi YJ, Tyagi R, Hallsworth-Pepin K, Mann VH, Kammili L, Latham PS....Food borne trematodes (FBTs) are an assemblage of platyhelminth parasites transmitted through the food chain, four of which are recognized as neglected tropical diseases (NTDs). Fascioliasis stands out among the other NTDs due to its broad and significant impact on both human and animal health, as Fasciola sp., are also considered major pathogens of domesticated ruminants. Here we present a reference genome sequence of the common liver fluke, Fasciola hepatica isolated from sheep, complementing previously reported isolate from cattle. A total of 14,642 genes were predicted from the 1.14 GB gen...
Canisso IF, Segabinazzi LGTM, Fedorka CE.Post-breeding endometritis (i.e., inflammation/infection of the endometrium), is a physiological reaction taking place in the endometrium of mares within 48 hours post-breeding, aimed to clear seminal plasma, excess sperm, microorganisms, and debris from the uterine lumen in preparation for the arrival of an embryo. Mares are classified as susceptible or resistant to persistent breeding-induced endometritis (PBIE) based on their ability to clear this inflammation/infection by 48 hours post-breeding. Mares susceptible to PBIE, or those with difficulty clearing infection/inflammation, have a def...
Costa MC, Weese JS.The equine intestinal tract contains a complex microbial population (microbiota) that plays an important role in health and disease. Despite the undeniable importance of a 'normal' microbiota, understanding of the composition and function of this population is currently limited. As methods to characterize the microbiota and its genetic makeup (the microbiome) have evolved, the composition and complexity of this population are starting to be revealed. As is befitting a hindgut fermenter, members of the Firmicutes phylum appear to predominate, yet there are significant populations of numerous ot...
Prokhorov NS, Riccio C, Zdorovenko EL, Shneider MM, Browning C, Knirel YA, Leiman PG, Letarov AV.Bacteriophages recognize and bind to their hosts with the help of receptor-binding proteins (RBPs) that emanate from the phage particle in the form of fibers or tailspikes. RBPs show a great variability in their shapes, sizes, and location on the particle. Some RBPs are known to depolymerize surface polysaccharides of the host while others show no enzymatic activity. Here we report that both RBPs of podovirus G7C - tailspikes gp63.1 and gp66 - are essential for infection of its natural host bacterium E. coli 4s that populates the equine intestinal tract. We characterize the structure and funct...
Julliand V, Grimm P.In the early 1990s, the equine hindgut microbial ecosystem looked like a "black box." Its vital role in hydrolyzing and fermenting fiber, thus providing energy to the host, was recognized. Although there was a critical lack of information on the hindgut microbes, their role in preventing intestinal diseases was suggested. Traditionally, the microbes of the horse hindgut were studied using culture-dependent techniques. More recently, culture-independent methods have been used and provided further insight. This review presents the history and updated knowledge regarding the microbes that live in...
Al Jassim RA, Andrews FM.The gastrointestinal tract of the horse has unique characteristics that make it well suited for the ingestion and utilization of roughage. The horse is considered a simple-stomached herbivore and is classed as a hindgut fermenter. The upper segments of the gastrointestinal tract resemble those of a typical simple-stomached animal. The lower have undergone modification to become voluminous and host to a large number of microbial populations similar to those of the compartmental stomach of ruminant animals. The main advantage of this arrangement is the ability of the horse to extract valuable nu...
Båverud V, Gustafsson A, Franklin A, Aspán A, Gunnarsson A.Clostridium difficile has been associated with acute colitis in mature horses. Objective: To survey C. difficile colonisation of the alimentary tract with age, occurrence of diarrhoea and history of antibiotic therapy; and to study the occurrence and survival of C. difficile in the environment and antimicrobial susceptibility of isolated strains. Methods: A total of 777 horses of different breeds, age and sex were studied. Further, 598 soil samples and 434 indoor surface samples were examined. Antimicrobial susceptibility of 52 strains was investigated by Etest for 10 antibiotics. Results: In ...
DebRoy C, Maddox CW.The pathogenic strains of Escherichia coli recovered from the intestinal tract of animals fall into categories called enterotoxigenic, enteropathogenic, enterohemorrhagic and necrotoxigenic. The other two categories, enteroinvasive and enteroaggregative, have not been reported in animals. The pathogenicity of these strains is determined by the presence of certain genes that encode adhesins and toxins, are generally organized in large blocks in chromosomes, large plasmids or phages, and are often transmitted horizontally between strains. In this review, we summarize current knowledge of the vir...
Miller TL, Lin C.Formal nomenclature is proposed for five methanogens, isolated from horse, pig, cow, goose and sheep faeces, that represent four novel species of the genus Methanobrevibacter. The four species, Methanobrevibacter gottschalkii sp. nov., Methanobrevibacter thaueri sp. nov., Methanobrevibacter woesei sp. nov. and Methanobrevibacter wolinii sp. nov., are distinguished from each other by a lack of genomic DNA reassociation and from previously described members of the genus on the basis of differences in the sequences of the 16S rRNA genes.
Janvilisri T, Scaria J, Thompson AD, Nicholson A, Limbago BM, Arroyo LG, Songer JG, Gröhn YT, Chang YF.Clostridium difficile is a gram-positive, spore-forming enteric anaerobe which can infect humans and a wide variety of animal species. Recently, the incidence and severity of human C. difficile infection has markedly increased. In this study, we evaluated the genomic content of 73 C. difficile strains isolated from humans, horses, cattle, and pigs by comparative genomic hybridization with microarrays containing coding sequences from C. difficile strains 630 and QCD-32g58. The sequenced genome of C. difficile strain 630 was used as a reference to define a candidate core genome of C. difficile a...
Mach N, Foury A, Kittelmann S, Reigner F, Moroldo M, Ballester M, Esquerré D, Rivière J, Sallé G, Gérard P, Moisan MP, Lansade L.Weaning has been described as one of the most stressful events in the life of horses. Given the importance of the interaction between the gut-brain axis and gut microbiota under stress, we evaluated (i) the effect of two different weaning methods on the composition of gut microbiota across time and (ii) how the shifts of gut microbiota composition after weaning affect the host. A total of 34 foals were randomly subjected to a progressive (P) or an abrupt (A) weaning method. In the P method, mares were separated from foals at progressively increasing intervals every day, starting from five min ...
Riddle WT, LeBlanc MM, Stromberg AJ.Endometrial cytology and culture specimens (n=2123) were collected concurrently with a guarded uterine culture instrument from 970 mares (738 barren, 1230 foaling and 155 maiden mares) during three breeding seasons (2001-2004). Results were compared to the 28-d pregnancy rate for the cycle from which the samples were taken. Cytological smears were evaluated for inflammation at x100 and graded as: not inflammatory (0-2 neutrophils/field), moderate inflammation (2-5 neutrophils/field), severe inflammation (>5 neutrophils/field), or hypocellular (scant epithelial cells and no neutrophils). Ute...
Walther B, Monecke S, Ruscher C, Friedrich AW, Ehricht R, Slickers P, Soba A, Wleklinski CG, Wieler LH, Lübke-Becker A.Despite the increasing importance of methicillin-resistant Staphylococcus aureus (MRSA) in veterinary medicine, knowledge about the epidemiology of the pathogen in horses is still poor. The phylogenetic relationship of strains of human and equine origins has been addressed before, usually by analyzing results of common standard classification methods for MRSA. This work intends to go beyond the baseline of typing procedures in order to comparatively characterize equine and human MRSA strains with similar phylogenetic backgrounds. In addition to multilocus sequence typing, pulsed-field gel elec...
Anderson MA, Whitlock JE, Harwood VJ.Escherichia coli is the most completely characterized prokaryotic model organism and one of the dominant indicator organisms for food and water quality testing, yet comparatively little is known about the structure of E. coli populations in their various hosts. The diversities of E. coli populations isolated from the feces of three host species (human, cow, and horse) were compared by two subtyping methods: ribotyping (using HindIII) and antibiotic resistance analysis (ARA). The sampling effort required to obtain a representative sample differed by host species, as E. coli diversity was consis...
Higuera A, Herrera G, Jimenez P, García-Corredor D, Pulido-Medellín M, Bulla-Castañeda DM, Pinilla JC, Moreno-Pérez DA, Maloney JG, Santín M.... is frequently reported in fecal samples from animals and humans worldwide, and a variety of subtypes (STs) have been observed in wild and domestic animals. In Colombia, few studies have focused on the transmission dynamics and epidemiological importance of in animals. In this study, we characterized the frequency and subtypes of in fecal samples of domestic animals including pigs, minipigs, cows, dogs, horses, goats, sheep, and llama from three departments of Colombia. Of the 118 fecal samples included in this study 81.4% ( = 96) were positive for using a PCR that amplifies a fragment of t...
Julliand V, de Vaux A, Millet L, Fonty G.Detection and quantification of cellulolytic bacteria with oligonucleotide probes showed that Ruminococcus flavefaciens was the predominant species in the pony and donkey cecum. Fibrobacter succinogenes and Ruminococcus albus were present at low levels. Four isolates, morphologically resembling R. flavefaciens, differed from ruminal strains by their carbohydrate utilization and their end products of cellobiose fermentation.
Islam MZ, Espinosa-Gongora C, Damborg P, Sieber RN, Munk R, Husted L, Moodley A, Skov R, Larsen J, Guardabassi L.Denmark is a country with high prevalence of livestock-associated methicillin-resistant Staphylococcus aureus (MRSA) clonal complex (CC) 398 in pigs. Even though pig farming is regarded as the main source of human infection or colonization with MRSA CC398, 10-15% of the human cases appear not to be linked to pigs. Following the recent reports of MRSA CC398 in horses in other European countries and the lack of knowledge on S. aureus carriage in this animal species, we carried out a study to investigate whether horses constitute a reservoir of MRSA CC398 in Denmark, and to gain knowledge on the ...
Biddle AS, Black SJ, Blanchard JL.Laminitis is a chronic, crippling disease triggered by the sudden influx of dietary starch. Starch reaches the hindgut resulting in enrichment of lactic acid bacteria, lactate accumulation, and acidification of the gut contents. Bacterial products enter the bloodstream and precipitate systemic inflammation. Hindgut lactate levels are normally low because specific bacterial groups convert lactate to short chain fatty acids. Why this mechanism fails when lactate levels rapidly rise, and why some hindgut communities can recover is unknown. Fecal samples from three adult horses eating identical di...
Vannucci FA, Gebhart CJ.Proliferative enteropathy is an infectious disease caused by an obligate intracellular bacterium, Lawsonia intracellularis, and characterized by thickening of the intestinal epithelium due to enterocyte proliferation. The disease is endemic in swine herds and has been occasionally reported in various other species. Furthermore, outbreaks among foals began to be reported on breeding farms worldwide within the past 5 years. Cell proliferation is directly associated with bacterial infection and replication in the intestinal epithelium. As a result, mild to severe diarrhea is the major clinical si...
Marx C, Gardner S, Harman RM, Van de Walle GR.Mesenchymal stromal cells (MSCs) from various species, such as humans, mice, and horses, were recently found to effectively inhibit the growth of various bacteria associated with chronic infections, such as nonhealing cutaneous wounds, via secretion of antimicrobial peptides. These MSC antimicrobial properties have primarily been studied in the context of the planktonic phenotype, and thus, information on the effects on bacteria in biofilms is largely lacking. The objectives of this study were to evaluate the in vitro efficacy of the MSC secretome against various biofilm-forming wound pathogen...
Golomidova A, Kulikov E, Isaeva A, Manykin A, Letarov A.The diversity of coliphages and indigenous coliform strains (ICSs) simultaneously present in horse feces was investigated by culture-based and molecular methods. The richness of coliforms (as estimated by the Chao1 method) is about 1,000 individual ICSs distinguishable by genomic fingerprinting present in a single sample of feces. This unexpectedly high value indicates that some factor limits the competition of coliform bacteria in the horse gut microbial system. In contrast, the diversity of phages active against any selected ICS is generally limited to one to three viral genotypes present in...
Mach N, Plancade S, Pacholewska A, Lecardonnel J, Rivière J, Moroldo M, Vaiman A, Morgenthaler C, Beinat M, Nevot A, Robert C, Barrey E.The adaptive response to extreme endurance exercise might involve transcriptional and translational regulation by microRNAs (miRNAs). Therefore, the objective of the present study was to perform an integrated analysis of the blood transcriptome and miRNome (using microarrays) in the horse before and after a 160 km endurance competition. A total of 2,453 differentially expressed genes and 167 differentially expressed microRNAs were identified when comparing pre- and post-ride samples. We used a hypergeometric test and its generalization to gain a better understanding of the biological functio...
Edwards JE, Shetty SA, van den Berg P, Burden F, van Doorn DA, Pellikaan WF, Dijkstra J, Smidt H.Equine gut microbiology studies to date have primarily focused on horses and ponies, which represent only one of the eight extant equine species. This is despite asses and mules comprising almost half of the world's domesticated equines, and donkeys being superior to horses/ponies in their ability to degrade dietary fiber. Limited attention has also been given to commensal anaerobic fungi and archaea even though anaerobic fungi are potent fiber degrading organisms, the activity of which is enhanced by methanogenic archaea. Therefore, the objective of this study was to broaden the current knowl...
Vengust M, Anderson ME, Rousseau J, Weese JS.To evaluate the prevalence of methicillin-resistant staphylococcal (MRS) colonization in clinically normal dogs and horses in the community. Results: Three hundred clinically normal horses and 200 clinically normal dogs were enrolled. One nasal swab was collected from each horse. Two swabs were taken from each dog: (i) from an anterior nare, and (ii) a combination of the perineal area and 0.5 cm into the anus. Enrichment cultures were performed. Methicillin-resistant Staphylococcus aureus (MRSA) was not identified. Methicillin-resistant Staphylococcus intermedius (MRSI) was isolated from the n...
Thiel PG, Marasas WF, Sydenham EW, Shephard GS, Gelderblom WC, Nieuwenhuis JJ.Fumonisins B1 (FB1) and B2 (FB2), two structurally related mycotoxins with cancer-promoting activity, were recently isolated from corn cultures of Fusarium moniliforme MRC 826. These toxins have been reported to be produced also by isolates of F. proliferatum. Contamination of foods and feeds by F. moniliforme has been associated with human esophageal cancer risk, and FB1 has been shown to be the causative agent of the neurotoxic disease leukoencephalomalacia in horses. Because of the toxicological importance of the fumonisins, the potential to produce FB1 and FB2 was determined in a study of ...
Schoster A, Mosing M, Jalali M, Staempfli HR, Weese JS.The intestinal microbiota is important for health and disease. Factors that disturb the equine intestinal microbiota need further investigation. Objective: To determine the effects of transport, fasting and anaesthesia on the faecal microbiota of healthy adult horses using next-generation sequencing. Methods: Experimental trial. Methods: Faecal samples were taken from 8 horses at baseline, after transport, 12 h of fasting and 24, 48 and 72 h after a 6 h anaesthesia. Next generation sequencing of the V4 region of the 16S rRNA gene was used to assess the microbial composition of faeces. Alpha...
