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.
Rogers HJ.Under a variety of conditions of concentration, Eh, and pH, horse anti- serum and normal horse serum exerted similar bacteriostatic effects against Type A. Ferric iron abolished the bacteriostatic effect when added during the first 2 hours of incubation at Eh+60 mV. Ferrous iron abolished the bacteriostatic effect when added after 3 hours. Ferric iron abolished the bacteriostatic effect at—140 mV. A mixture consisting of horse β- and γ-globulins together with human transferrin exerted a bacteriostatic effect similar to that of whole serum. This system responded in the same way as whole se...
Haque RU.A technique for identifying and characterizing staphylococcal hemolysins by first separating them electrophoretically in barbital-buffered agar gel (pH 8.4) at 5 ma/cm for 2 hr and then determining their hemolytic activities by exposing them to human, horse, rabbit, and sheep erythrocytes is described. The alpha-hemolysin produced by a White variant of the Wood 46 strain of Staphylococcus aureus migrated 18 mm towards the cathode, and it lysed horse, rabbit, and sheep erythrocytes, whereas a Clear variant of the Wood 46 strain of S. aureus produced a lysin which migrated similarly to the alpha...
Goebel WF, Staub AM.1. The immunization of horses with the colicinogenic bacillus E. coli K235 L + O(m) stimulates antibodies which precipitate and neutralize colicine K and neutralize the heterologous colicine I as well. 2. Unlike rabbits, horses evoke predpitating antibodies for the sialic acid-containing polysaccharide colominic acid.
HARDY FM, ARBITER D.Hardy, Frank M. (Fort Detrick, Frederick, Md.), and David Arbiter. Lipid inclusions in L cells associated with Venezuelan equine encephalomyelitis virus infection. J. Bacteriol. 89:1101-1103. 1965.-Venezuelan equine encephalomyelitis (VEE) virus has been shown to induce changes of lipid components within the L cell. Lipid inclusions in the form of dark granular bodies were observed in the L cell after aqueous osmium tetroxide fixation and Sudan black staining. Microscopic examination of cells as early as 8 hr after infection with VEE virus showed an increase in the concentration of these inclu...
BOYD WL, BOYD JW.Boyd, William L. (Ohio State University, Columbus) and Josephine W. Boyd. Viability of coliform bacteria in antarctic soil. J. Bacteriol. 85:1121-1123. 1963.-The distribution of coliform bacteria in soils of Ross Island and the nearby mainland was studied. None was found in almost all of the samples collected, including some from the Adelie penguin rookeries at Cape Royds and Cape Crozier and in soil at the McMurdo Base which had been recently contaminated by human sewage. Samples of pony manure left from previous expeditions were also negative, with one exception where Escherichia coli were p...
VAN UDEN N, DO SOUSA LC, FARINHA M.From the caeca of 252 horses, 503 sheep, 250 goats and 250 swine, 486 yeast isolates belonging to 28 species and 1 variety were obtained. The distribution of the yeasts of any species and for Candida albicans respectively was: horses, 52·4%, 4·4%; sheep, 6·8%, 4·2%; goats, 6·4%, 08%; swine, 88·8%, 9·2%. The suitability of the sheep and goats as hosts for yeasts of any species seems very limited.
The most frequent occurrences for single species were: Candida slooffii in swine (48·4%), Trichosporon cutaneum in horses (21·8%) and Saccharomyces tellustris (Candida bovina) in swine (14%...
ADAMS KM.The ciliate population of the large intestine of the horse shows large, daily variations. The ventral colon is the site where the ciliate fauna varies most. Two species, Cycloposthium edentatum and C. dentiferum, became established in the large intestine after passage through the stomach and small intestine. The introduction of new species into the ventral colon caused significant changes in the fauna of that part of the gut.
RANDALL CC, ORR MF, SCHELL FG.Intracellular organisms resembling Histoplasma capsulatum have been observed in apparently normal amnio-allantoic membrane and adult horse spleen maintained in tissue culture.
The significance of this finding and comparison with another fungus Cryptococcus jarciminosus is discussed.
Amaral Júnior FP, Souza de Sousa CE, Rafael de Almeida Moreira B, Rodrigues Alves BJ, Longhini VZ, da Silva Cardoso A, Ruggieri AC.There is an important gap in how variations in herbivore dung composition affect GHG emissions on pastures, especially due to differences in dry matter (DM) and nitrogen contents. Oversimplifications can compromise the accuracy of mitigation strategies. This study aims to address this gap by investigating how the chemical composition of dung from different species influences GHG emissions in pasture systems. The results showed that drier dung led to higher cumulative N₂O emissions. The highest emissions were observed from goat at 9.47 mg N-N₂O g⁻ dry soil, followed by sheep at 5.95 mg ...
Zu H, Sun R, Li J, Guo X, Wang M, Guo W, Wang X.Strangles, a highly contagious disease caused by subspecies (), significantly impacts horse populations worldwide, with Iceland as the only exception. This disease poses serious threats to equine health and results in considerable economic losses. Consequently, the accurate, sensitive, and rapid detection of from clinical samples is essential for early warning and effective disease management. This study introduces a novel detection method that integrates recombinase-aided amplification (RAA) with CRISPR/Cas12a technologies. We specifically designed RAA primers and CRISPR RNA to target the ...
Martin G, Tyson GH, Guag J, Strain E, Ceric O.Klebsiella spp. is an important human and animal pathogen, and it is commonly found with resistance to clinically important antimicrobials worldwide. The main goals of this study were to determine the prevalence of antimicrobial resistance genes in our study population and to assess the relatedness between Klebsiella spp. isolated from humans and animals. Isolates were collected in 2019 and 2020 from various animal hosts that presented to veterinary hospitals in the U.S. that participate in the FDA's Center for Veterinary Medicine Veterinary Laboratory Investigation and Response Network's anti...
Belhout C, Wang F, Rossano A, Collaud A, Fernandez JE, Marchionatti E, Keller JE, Overesch G, Kaessmeyer S, Schwendener S, Perreten V.Nine Gram-positive, non-motile, facultatively anaerobic cocci, designated EM39Eᵀ, JEK85, 18KM676, 21M1142, 18KM445, 18KM444, 18KM245, 18KM583 and 21KM1573, were isolated from diverse animal material, including horse and pig skin, bovine mastitis milk and feline urine from a urinary tract infection. Phylogenomic analysis based on amino-acid alignment obtained from translated whole-genome sequences; digital DNA-DNA hybridization (dDDH); 16S rRNA, , , and gene comparison; and MALDI-TOF MS spectral profiles placed the strains within the clade. They were closely related to CCM 7100ᵀ, CCM 7...
Tasnim Y, Rahman MK, Awosile B.We aimed to determine the genetic relatedness among β-lactamase-producing Escherichia coli isolated from soil, lake water, and feces of geese, pigs, dogs, cattle, coyotes, wild hogs, and horses at one health interface in West Texas. Results: Previously isolated 56 β-lactamase-producing E. coli isolates from the feces of geese, pigs, horses, coyotes, dogs, cattle, and wild hogs, and soil and lake water from different locations in West Texas were analyzed for genetic relatedness using whole-genome sequencing, core genome multilocus sequence typing, and phylogenetic single-nucleotide polymorphi...
Gomes-Gonçalves S, Mesquita JR, Ruano ZM, Barradas PF.Coxiella burnetii is a bacterium that causes coxiellosis in animals and Q fever in humans. While ruminants are the main reservoirs, the role of ticks in their transmission is still uncertain. This study looked for C. burnetii in ticks collected from two autochthonous breeds in Portugal: Churra Galega Mirandesa sheep and Garrano horses. A total of 555 ticks were tested, including 100 Rhipicephalus sanguineus sensu (s.) stricto (s.) from sheep and 455 Rhipicephalus bursa from horses. Coxiella burnetii was found in 7 % of R. sanguineus s.s., but not in R. bursa. Phylogenetic analysis confirmed th...
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...
Wang R, Ren W, Liu S, Li Z, Li L, Ma S, Yao X, Meng J, Zeng Y, Wang J.This study aimed to assess the anti-inflammatory properties of mare milk by analyzing immune markers in mice following gavage of mare milk. Metagenomic sequencing was employed to examine variations in the composition and functional profiles of the intestinal microbiota across different experimental groups. Bacterial diversity, abundance, and functional annotations of gut microbiota were evaluated for each group. The results show that, compared to the control group, the mare milk group exhibited a significant decrease in the pro-inflammatory cytokine IL-6 levels and a significant increase in se...
Ma S, Luo T, Zheng Y, Wang Y, Yu J, Qu H, Liu B, Wang T, Wu C, Zhu Y, Bai X, Wang Z, Li J.Endometritis is a major cause of infertility in intensively farmed donkeys. Streptococcus equi subsp. zooepidemicus (SEZ) is a predominant pathogen that readily forms biofilms in equine endometritis, conferring resistance to conventional treatments. Objective: This study aimed to characterize the biofilm dynamics of SEZ isolates obtained from donkeys and to evaluate potential anti-biofilm strategies with different drug combinations. Methods: Uterine lavage samples were collected from 30 Dezhou Black donkeys with clinical endometritis. Bacterial cultures were performed on blood agar and MacConk...
Hayashi M, Yonetamari J, Muto Y, Kinoshita Y, Uchida E, Niwa H, Fujiwara N, Nakaya M, Yamagishi Y, Tanaka K.In this study, five strains of anaerobic, Gram-negative, rod-shaped bacteria were characterized phenotypically, biochemically and genotypically. These strains were clinically isolated from horse specimens in Japan. Phylogenetic trees constructed based on 16S rRNA gene sequence comparisons showed distinct clustering of the five strains with the type strains of closely related species. The genomic DNA G+C content was 46.7 mol%. The major cellular fatty acids identified were C, 3-OH-C and 3-OH-iso-C. Whole-genome comparisons based on average nucleotide identity using blast (ANIb) and digital DNA...
Rymaszewska A, Kubiak K, Dmitryjuk M, Rząd I, Kirczuk L.Ixodes ricinus is a widespread vector of numerous microorganisms pathogenic to humans and animals in Europe. The risk of exposure to tick-borne pathogens (TBPs) has increased in recent years due to climate change, the conversion of natural green areas to recreational areas, and growing human and animal populations, including pets. Using molecular methods, the prevalence, diversity, and co-occurrence of selected tick-borne microorganisms were assessed in questing I. ricinus collected from recreational areas (n = 409), in ticks feeding on horses (n = 135), and in blood samples from red d...
Jimenez Rihuete P, Martin C, Villarino NF, Rubio-Martínez LM.Silica-sprayed tubes (SSTs) are often used to transport synovial fluid samples in equine practice. They promote the coagulation of the sample. The objective of the study is to evaluate the effect of SST on bacterial culture. The study was divided into two parts: sterile saline (Part A) and synovial fluid (Part B). Four common bacteria associated with equine synovial sepsis were used: Streptococcus pyogenes, Escherichia coli, Staphylococcus aureus and methicillin-resistant S. aureus (MRSA). Three collection tubes were used: STT, plain (no-additives) and brain and heart infusion (BHI) broth. Bac...
Abdulkadir A, Kabir J, Bello M, Olayinka B.Methicillin resistant Staphylococcus aureus (MRSA) represents a worrying example of antimicrobial resistance, and it is essential to acquire new information to monitor the spread and limit it further diffusion. This study aimed to characterise 22 MRSA isolates from horses, dogs, cats, and their human handlers focusing on spa typing. In the analysis of the sequences obtained, the spa type is "unknown" (unidentified) and all the sequences except one had repeats previously not known in all databases potentially indicating new spa-repeats. This could possibly indicate either permanent import of no...
Ma Y, Zhang J, Li X, Zhao H, Lu W, Li H, Yang K.Anthelmintic treatment is widely used in equine health management to control parasitic infections; however, its potential effects on the gut microbiota and metabolic characteristics remain poorly understood. In this study, twelve Yili horses were randomly assigned to two groups: a control group (C), which received no anthelmintic treatment, and a Miechongshu-treated group (T), which was orally administered Miechongshu at a dose of 0.36 g/kg body weight on day 0. Fecal samples were collected from the rectums of Yili horses on day 14 after administration, and differences in gut microbial composi...
Ilbeigi K, Mabille D, Roy R, Bundschuh M, Van de Velde E, Hulpia F, Van Calenbergh S, Caljon G.Surra and Dourine are widespread diseases caused by two protozoan parasites Trypanosoma brucei evansi and Trypanosoma brucei equiperdum, respectively. A wide range of animals including camels, horses, cattle and buffaloes are susceptible to infection. These diseases pose a significant socio-economic burden, primarily due to the limited therapeutic options and the complications associated with toxicity and drug resistance, making disease management particularly challenging. This study evaluated the potential of 3'-deoxytubercidin, a previously identified antitrypanosomal nucleoside, as a therap...
Seeger MG, Correa DC, Barcelos RAD, Werle J, Masuda EK, Bordin AI, Cohen ND, Vogel FSF, Cargnelutti JF.Strangles is a common infectious disease caused by Streptococcus equi subspecies equi (S. equi) that primarily affects the upper respiratory system. To date, 271 alleles of the M protein (seM) have been identified that may be related to antigenic differences of isolates. This study evaluated the virulence of S. equi isolates from different alleles of the M protein in an experimental mouse model. Thirty-six Swiss mice were allocated into 12 groups (G1-G12) and each infected group received a different isolate of S. equi recovered from horses with strangles: G1: seM-117; G2: seM-61; G3: seM-123; ...
Ma R, Wang C.Gut microbiota is vital to host health, involving many aspects including immunity, metabolism and digestion. Exercise is recognized as a significant factor influencing the gut microbiota. However, the effects of exercise on the gut microbiota in horses remain unclear. Here, this study aims to investigate the effects of exercise on the gut bacterial and fungal communities in the horses using 16S rDNA and ITS genes amplicon sequencing. Results indicated that exercise significantly increased the ACE, Chao1 and Shannon indices of the gut bacterial community, accompanied by significant alterations ...
Houben RMAC, Broens EM, Broekhuizen-Stins MJ, Sloet van Oldruitenborgh-Oosterbaan MM, van Maanen C, Heesterbeek JAP.Streptococcus equi subspecies equi (S. equi) carriers are thought to be important drivers for strangles outbreaks. Limited data are available on the prevalence of carriers in European horse husbandry settings. Objective: To estimate the prevalence of S. equi carriers among apparently healthy adult horses and ponies in the Netherlands. Methods: Cross-sectional survey. Methods: The carrier prevalence in the Netherlands was estimated, detecting carriers by PCR analysis of three repeated nasopharyngeal lavages at weekly intervals. Bayesian methods were used for a true prevalence estimation. Result...
The animal microbiome plays a crucial role in determining the health, productivity, and welfare of livestock species, including sheep, horses, cattle, camel, and chicken. These animal species were selected due to the high consumption of their products in Kazakhstan. Enhancing their productivity, while maintaining the safety and quality of meat and milk derived from them, represents a pressing research priority. This review article includes current research on the composition, diversity, and purposes of the microbiota found within different organ systems of these species. This study focuses on ...
van Heule M, Heil B, Norris JK, Gedye K, Lin X, De Spiegelaere W, Daels P, Dini P.Ascending placentitis is a leading cause of late-term pregnancy loss in mares. Although pathogens are presumed to ascend from the caudal reproductive tract, the association between the vaginal microbiome and placentitis has not been systematically examined. Objective: To characterise microbial and host gene expression in the equine vagina during gestation and to identify taxa or transcripts that were associated with the presence of an abnormal placenta at birth. Methods: Prospective, paired observational study. Methods: Vaginal wall swabs were collected from 49 multiparous Thoroughbred mares a...
Jackson K, Quintrell E, Staszyk C, Ha W, Kelty E, Patalwala D, Bogen G.Equine endodontic treatment for apical infections is performed infrequently due to anatomical and accessibility challenges of equine cheek teeth. However, the alternative of extraction is not without risk and lifelong implications for the horse. Mineral trioxide aggregate (MTA), a calcium silicate cement (CSC), has been used successfully in human dentistry for decades. MTA and other CSCs demonstrate excellent biocompatibility with favourable antimicrobial and physicochemical properties. These characteristics may support their application as an alternative filling material when used in equine e...
Khalil WA, Mostafa HE, Derbala MK, Hassan MAE, Abdelnour SA, El-Harairy MA.This experiment explores the comparative ability of vitamin E (VE) and its nano-emulsion (VEN) in enhancing cryo-resistance of stallion spermatozoa by examining semen quality, kinematic variables, acrosome integrity, apoptosis, antioxidant capacity, ultra-structural alterations and microbiota of cryopreserved stallion sperm. Semen from five stallions (8-10 years) was cryopreserved with 0.1 or 1 mM of VE or VEN; and a non-additive group served as the control. The VEN particles ranged in size from 72 to 172 nm, with a mean diameter of 287 nm. Supplementation with VE (1 mM) or VEN (0.1 ...
Guo L, Holyoak GR, DeSilva U.The Earth's estimated 10 virions, primarily phages, significantly impact microbial ecosystems. Despite their abundance, viromes remain relatively understudied-particularly in domestic animals. While recent studies have described a dynamic commensal microbiome in mammalian uteri, no research has yet characterized the commensal virome in a mammalian uterus. In this study, we report for the first time the presence of a sparse, but diverse native virome in the equine uterus. The resulting virome database consists of 513 non-redundant viral genomes (> 2 kb). Taxonomic annotations revealed the...
Wang T, San Juan MR, Choi H, Hwang M, Jinadatha C, Navarathna DH. subspecies (SESZ) is an uncommon zoonotic pathogen in humans but can cause severe joint infections. Reported cases are often linked to exposure to horses, dairy products, or raw pork, though infections may occur without an identifiable animal source. Unassigned: An 84-year-old man with multiple comorbidities presented with acute left shoulder pain, fever, and chills. Synovial fluid aspiration yielded turbid fluid containing calcium pyrophosphate dihydrate crystals, while Gram stain was negative. Despite empiric broad-spectrum antibiotics, his symptoms persisted, requiring surgical irrigation...
Pelenė U, Šiukščius A, Nainienė R, Merkelytė I, Šveistienė R.The equine reproductive microbiota has emerged as an important factor influencing reproductive health and fertility in both mares and stallions. Traditionally, the equine uterus was considered sterile, and microbial presence was interpreted primarily in the context of infection. However, sequencing-based studies have demonstrated that the reproductive tract, including the uterus and semen, contains detectable microbial communities or microbial DNA signatures, challenging this traditional paradigm. In mares, the vaginal microbiota is consistently dominated by , , , and , whereas the uterine env...
Ren J, Ma C, Yang K, Li X, Yang F, Guo X, Yao X, Wang C.Zn-CS chelate has shown beneficial effects on gut health and growth in piglets, but its impact on weaned foals remains largely unknown. This study evaluated the effects of dietary Zn-CS supplementation on growth performance, nutrient digestibility, physiological status, and fecal microbiota in weaned Ili foals. Thirty-two six-month-old foals were randomly assigned to four treatment groups receiving 0, 2, 4, or 6 mg Zn-CS/kg body weight per day for 90 days. Growth performance, nutrient digestibility, plasma biochemical parameters, liver function enzymes, serum hormones, antioxidant indices, fec...
Mair E, Nekouei O, Trummer-Schug P, Haralambus R, Biermann NM.Age-related dental changes are major contributors to dental disorders in older horses, and cheek tooth extractions are often required to maintain masticatory function and oral comfort. However, limited information is available on clinical and treatment characteristics in this older patient population. Objective: To describe clinical features, treatments, complication rates and short-term outcomes of horses undergoing oral cheek tooth extraction and treatment of odontogenic sinusitis, and to compare findings between geriatric and non-geriatric horses. Methods: Retrospective analysis of clinical...
Paillot R, Newton JR, Gonzalez Medina S, Frosth S, Frykberg L, Flock M, Guss B, Flock JI, Waller AS.Streptococcus equi subspecies zooepidemicus is a highly diverse opportunistic pathogen of horses, associated with respiratory disease and endometritis. Objective: To characterise S. zooepidemicus isolates recovered from young ponies during a natural episode of respiratory disease, and to determine if vaccination with Strangvac®, a vaccine against Streptococcus equi subspecies equi, conferred cross-protection. Methods: Retrospective analysis of a double-blinded placebo-controlled study involving 32 ponies (16 vaccinates and 16 placebo controls) that experienced a natural episode of respiratory...
El-Halim MOA, Shoraba M, Gattan HS, Alruhaili MH, Selim A.Staphylococcus aureus is a common commensal organism in both humans and animals, frequently colonizing the skin and nasal cavities of healthy individuals, although it can also cause a wide range of severe infections. The present study investigated the prevalence and risk factors of S. aureus in equines, along with antimicrobial resistance patterns of methicillin-resistant S. aureus (MRSA) isolates. The results revealed a prevalence of 38.6% in nasal samples collected from equines, highlighting the organism's significant presence and potential to cause infections in these animals. A genotypic p...
Rochegüe T, Hughes S, Saras E, Gillet B, Drapeau A, Glaser P, Madec JY, Haenni M, Lupo A.In streptococci, the acquisition of high-level gentamicin resistance (HLGR) abolishes the synergy with beta-lactams, constituting a medical concern for humans and animals. This synergy between gentamicin and beta-lactams is useful to treat severe infections like endocarditis, among others. HLGR has been characterized mostly in roup B Streptococci mediated by the bi-functional gene (6)-(2).HLGR- subsp. () (=27) were isolated from the uterus of mares during a routine screening before fecundation. One HLGR- was isolated from a lymph node of a mare. The mares resided in six different studs locat...
