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.
The potential of effective microorganisms in composting animal manure might be significant. This work aimed at isolating promising microbial strains for composting cattle and horse manure. A total of forty-five isolates have been isolated from soils of Northern Kazakhstan as well as cattle and horse manure. These microorganisms were extensively studied for their cellulose-degrading capacity, non-pathogenicity, protease, nitrogenase and catalase activities, as well as their growth stimulation, antagonistic ability, and growth rate. As a result, 21 potent strains were selected and genotyped for ...
Cito F, Di Francesco CE, Averaimo D, Chiaverini A, Alessiani A, Di Domenico M, Cresci M, Rulli M, Cantelmi MC, Di Bernardo MD, Giammarino A.... subsp. (SEZ) is a major problem in equine veterinary medicine. Typically, a commensal in horses, SEZ can cause severe disease including respiratory infections, septicaemia and reproductive tract infections under certain conditions. Recent evidence suggests that humans can also develop severe disease infection through direct contact with infected animals or the consumption of contaminated unpasteurised milk and milk products. This study investigates SEZ strains isolated from nasal swabs of equidae in central Italy in 2023 to describe the epidemiology and genomic characteristics of circulating...
Villa RE, Azimonti G, Bonos E, Christensen H, Durjava M, Dusemund B, Gehring R, Glandorf B, Kouba M, López-Alonso M, Marcon F, Nebbia C, Pechová A....Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety of a feed additive consisting of NCIMB 30336 (BioWorma®) for all grazing animals other than dairy bovines, ovines and caprines (namely, grazing animals from the following species: pigs (all categories), rabbits (all categories), horses (all categories) and calves/kids of species in the family Cervidae (deer, etc.) and Camelidae (alpacas, etc)). The safety and efficacy of the additive have already been assessed...
Mizani A, Taherkhani P, Kia Lashaki E, Hosseini SA, Basirpour B, Dodangeh S.Giardia duodenalis as a common zoonotic parasite is a public health problem infecting humans and a wide range of animals, including horses. This systematic review and meta-analysis was conducted to estimate the global pooled prevalence of Giardia infection in horses. Literature searches were conducted using databases including Scopus, ScienceDirect, PubMed, Web of Science and ProQuest to December 2023. A random-effect model was performed to calculate the pooled prevalence and corresponding 95% confidence interval (CI) according to the degree of heterogeneity in the included studies. Of 2661 ar...
Sun YF, Han ZX, Yao XK, Meng J, Ren WL, Wang CK, Yuan XX, Zeng YQ, Wang YF, Sun ZW, Wang JW.: The aim of this study was to investigate the effects of different stages of training on the intestinal microbial abundance of Yili horses. : Ten Yili horses, all aged 2 years old and weighing 305 ± 20 kg, were selected and divided into a training group and an untrained group. The training group performed riding training 6 days a week, and the untrained group moved freely in the activity circle every day. Fecal samples were collected on days 30 and 60, and the intestinal microorganisms were detected and analyzed using metagenomics. : Compared with the 30-day untrained group, the relative abu...
Kinoshita Y, Niwa H, Ueno T.In horses, the gut microbiota plays a critical role in maintaining intestinal homeostasis and overall health, but antimicrobial administration can disrupt its balance, resulting in dysbiosis, which can cause antibiotic-associated diarrhea. This study assessed the impact of intravenous cephalothin sodium administration on the equine gut microbiota by using microbial amplicon sequencing targeting the 16S-ITS-23S rRNA operon. Fecal samples from 39 clinically normal horses, 16 antibiotic-treated horses (cephalothin, n=5; minocycline, n=5; metronidazole, n=6, each administered for 5 days), and seve...
Cerullo A, Di Nicola MR, Scilimati N, Bertoletti A, Pollicino G, Moroni B, Pepe M, Nannarone S, Gialletti R, Passamonti F.Bacterial contamination of the surgical site in horses is a major risk factor for the development of surgical site infections (SSIs), which increase morbidity, mortality, the hospitalisation period, antibiotic use, and management costs. While contamination is a prerequisite for infection, its progression to clinical infection depends on additional factors that compromise host defences. The present study, conducted at the Veterinary Teaching Hospital of the University of Perugia over an 11-month period, investigated bacterial contamination in 70 surgeries (53 clean and 17 clean-contaminated) at...
da Silva-Álvarez E, Gómez-Arrones V, Correa-Fiz F, Martín-Cano FE, Gaitskell-Phillips G, Carrasco JJ, Rey J, Aparicio IM, Peña FJ, Alonso JM....This study aims to unveil potential differences in the vaginal and uterine microbiomes in mares and jennies, and to identify possible mechanisms involved in uterine immune homeostasis. The microbiota was characterized using 16S rRNA sequencing, and the uterine proteome was analyzed using UHPLC/MS/MS in 18 samples from healthy mares and 14 from jennies. While taxonomic analysis revealed high interspecies similarities, β-diversity analysis showed distinct clustering, with only two vaginal taxa and five uterine taxa differing between species. Despite compositional differences, PICRUSt analysis s...
Li Y, Lan Y.The gut microbial importance and its crucial roles in host digestion, immunity, and metabolism have received widely attention. Horses, especially indigenous varieties such as Mongolian horses (MGH) and Guizhou horses (GZH), have not received sufficient attention, and the characteristics of their gut microbiota are still unclear. For this purpose, we collected faecal samples from eight MGH and eight GZH to compare their gut microbial differences using amplicon sequencing. The results of alpha diversity analysis indicated that the gut bacterial diversity and gut fungal abundance in GZH were sign...
Boshuizen B, De Maré L, Oosterlinck M, Van Immerseel F, Eeckhaut V, De Meeus C, Devisscher L, Vidal Moreno de Vega C, Willems M, De Oliveira JE....Aleurone, derived from the bran layer of grains like wheat and barley, has demonstrated positive effects on energy metabolism in pigs, mice, and untrained horses, influencing glucose-insulin dynamics and gut microbiome composition. Training itself enhances insulin sensitivity in horses, similar to the improvements in performance capacity observed in human athletes. This study aimed to investigate whether aleurone supplementation provides additional benefits to training by modulating insulin metabolism and gut microbiota in Standardbred mares. Unassigned: Sixteen Standardbred mares (aged 3-5 ye...
Kukhar Y, Bailina G, Smagulova A, Uakhit R, Kiyan V.Equine skin mycoses are a significant concern in Kazakhstan's livestock industry due to the country's historical livestock farming practices, the development of equestrian sports, and food traditions. Skin infections are among the most common fungal infections in horses. Emerging pathogens of equine dermatophytosis include keratinophilic Chrysosporium spp., which can degrade and metabolize keratin found in superficial tissues. This, combined with their thermotolerance, contributes to their pathogenicity. In this study, we investigated the biological properties and pathogenicity of two Chrysosp...
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; ...
Carvalho IB, Branco S, Laranjo M, Queiroga MC, Bettencourt E.Uterine health is paramount to fertility in broodmares and for the success of a breeding project, and the Lusitano breed is no exception. This study aimed to characterize the mare uterine microbiota using practical clinical evaluation methods. Mares were examined by transrectal palpation and ultrasonography, followed by the collection of samples by one of three different techniques: uterine lavage, biopsy, or swab. The results of cytology, histology, microbiology, and antimicrobial susceptibility testing were recorded, and statistical analyses were performed. Inflammation was present in 42.2% ...
Klymiuk MC, Speer J, Marco I, Elashry MI, Heimann M, Wenisch S, Arnhold S.Osteoarthritis (OA) is a common and incurable disease in humans and animals. To gain a better understanding of the pathogenesis and identify potential treatments, miRNAs will be extracted and analysed from extracellular vesicles (EVs) of equine adipose derived mesenchymal stem cells (AdMSCs). Methods: For this purpose we cultivated and pretreated AdMSCs under different conditions: interleukin 1β, shock wave, chondrogenic differentiation, chondrogenic differentiation under hypoxia, or after senescence. After treatment, EVs were harvested from the cell culture supernatants. Next-generation sequ...
Castanheira CIGD, Anderson JR, Clarke EJ, Hackl M, James V, Clegg PD, Peffers MJ.This study describes a novel technique to analyze the extracellular vesicle (EV)-derived microRNA (miRNA) crosstalk between equine chondrocytes and synoviocytes. Donor cells (chondrocytes, n = 8; synoviocytes, n = 9) were labelled with 5-ethynyl uridine (5-EU); EVs were isolated from culture media and incubated with recipient cells (chondrocytes [n = 5] were incubated with synoviocyte-derived EVs, and synoviocytes [n = 4] were incubated with chondrocyte-derived EVs). Total RNA was extracted from recipient cells; the 5-EU-labelled RNA was recovered and sequenced. Differential expression analysi...
Polo MC, Huby FD, Uehlinger FD, Rubin JE.Antimicrobial resistance is a serious threat in human and veterinary medicine. Among the most problematic resistant organisms are the extended-spectrum β-lactamase (ESBL)-producing Enterobacterales, which are resistant to the 3rd-generation cephalosporins. The purpose of this study was to determine the frequency of colonization of horses admitted to the Western College of Veterinary Medicine with resistant Escherichia coli. Unassigned: Rectal swabs were collected from 60 horses admitted between November 2021 and March 2022. Swabs were selectively cultured for E. coli, which was identified usi...
Hain-Saunders NMR, Knight DR, Harvey A, Bruce M, Hampson BA, Riley TV.Clostridioides difficile is a known cause of diarrhea and colitis in human and non-human animals. While C. difficile is regularly isolated from domesticated horses, little is known about its prevalence in wild or feral populations. In Australia, the horse population encompasses a mix of both domesticated and feral animals, with the feral population of 400,000 estimated to be the largest in the world. This study investigated the presence and characteristics of C. difficile in Australian feral horses and evaluated their potential as a source or reservoir of C. difficile in the wider community. F...
The emergence of new strains in the Mediterranean region poses a challenge for both veterinary medicine and public health, as it can lead to more complex diagnostic and treatment strategies. Species related to and , two important tick-borne pathogens, have been reported in several Mediterranean countries. However, the data on their presence in Sardinia remain limited. This study aimed to such as or , in Using various molecular approaches targeting the and genes, the results confirm the presence of () and reveal the emergence of () and an -like strain, designated as -like 2, in Sardi...
Simms N, Bertone JJ, Melgarejo T, O'Shea C, Linde A.Emerging research suggests the presence of a blood microbiome in clinically healthy individuals. Characterizing bacterial composition and abundance in blood from a group of healthy horses is of clinical interest. Objective: Horses in a closed herd environment will have blood microbiomes with similarities among individuals. Methods: Twenty trail-riding horses of different breeds and ages living in relative isolation on a dry lot pasture in Colorado at 7680 ft elevation. Methods: Cross-sectional study. Blood was collected from the jugular vein into serum, blood collection, and EDTA tubes. Samp...
Laroche N, Grimm P, Julliand S, Sorci G.Sainfoin (Onobrychis viciifolia), a polyphenol-rich plant, has shown promising anti-parasitic properties in ruminants, but results in horses are fewer and inconsistent. The mechanisms of action involved are not fully understood and different factors may influence its anti-parasitic properties. Recently, it has been shown that the effect of sainfoin depends on the horse's diet. Indeed, the inclusion of dehydrated sainfoin pellets in a high starch diet limited the rate of increase in strongyle egg shedding over a short period of time (21 days). The objective of this study was to evaluate, in viv...
Wilson HJ, Dong J, van Tonder AJ, Ruis C, Lefrancq N, McGlennon A, Bustos C, Frosth S, Léon A, Blanchard AM, Holden M, Waller AS, Parkhill J. subsp. causes the equine respiratory disease 'strangles', which is highly contagious, debilitating and costly to the equine industry. emerged from the ancestral subsp. and continues to evolve and disseminate globally. Previous work has shown that there was a global population replacement around the beginning of the twentieth century, obscuring the early genetic events in this emergence. Here, we have used large-scale genomic analysis of and its ancestor to identify evolutionary events, leading to the successful expansion of . One thousand two hundred one whole-genome sequences of were ...
Gravey F, Sévin C, Langlois B, Maillard K, Foucher N, Duquesne F, Léon A, Le Hello S, Petry S.Misidentifications as Klebsiella pneumoniae were observed during a French retrospective study of a necropsy-associated K. pneumoniae bacterial collection from horses. Accordingly, the present study aimed to further characterise the 12 Raoultella spp. and Klebsiella spp. strains involved in these misidentifications. The strains were identified and characterised using the Api 20E system, K. pneumoniae PCR detection, matrix-assisted laser desorption/ionisation time-of-flight mass spectroscopy and whole-genome sequencing. Antimicrobial susceptibilities were tested by the disc diffusion method with...
Curadi MC, Vallone F, Tenuzzo M, Gazzano A, Gazzano V, Macchioni F, Vannini C.The gut microbiota plays a basic role in maintaining the psychophysical health and well-being of horses. Understanding the complex interactions among microbial communities in relation to age, management, and health is a topic of growing interest. The equine microbiota, given its complexity, is subject to variations caused by internal or external stressors that can lead to metabolic problems and pathologies, i.e., obesity and laminitis. The aim of this study was to characterize the fecal microbiota of 12 purebred Arabian horses and to compare the microbial communities in two distinct management...
Zhang W, Guo R, Sulayman A, Sun Y, Liu S.Microbiota in the gastrointestinal tract play a crucial role in nutrient digestion, health and so forth in equines. As the research attention on gut microbes has increased, several studies have investigated the composition of the gastrointestinal microbial flora in equines. This article reviews the effects of breed, age, intestinal site, nutritional management and diseases on the gastrointestinal microbiota of horses and donkeys, thus offering references for improving the gastrointestinal microecological environment in these animals and preventing and controlling disease occurrence in them.
Allano M, Arsenault J, Archambault M, Fairbrother JH, Sauvé F.Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of nosocomial infections, including in veterinary settings. Objective: To investigate the prevalence, risk factors for Staphylococcus aureus (SA) and MRSA colonization, and the duration of MRSA colonization. Methods: Elective cases admitted to the Veterinary Teaching Hospital were recruited (228 horses). Methods: A cross-sectional study was conducted over 3 years. Nasal swabs were collected at admission and cultured for SA. Methicillin-resistant isolates were identified using matrix-assisted laser desorption/ionization-time-...
Marchi S, Amodeo D, Peccetti B, De Palma I, Messina G, Montomoli E, Trombetta CM.Influenza D virus (IDV) is a novel influenza virus, first isolated from swine with influenza-like symptoms in the USA in 2011. To date, IDV circulation has been reported in various animal species such as cattle, pigs, horses with the ability to expand its range of hosts. UV radiation has been widely used for the disinfection of various sources such as water, air, and surfaces, especially in places at greater risk of contamination by viruses and bacteria, such as hospitals and health facilities. The aim of this study was to evaluate the potential virucidal effect of a violet-blue light against ...
Snedden K, Frye E, Conklin R, Aprea M, Rishniw M, Lejeune M, Goodrich E.To analyze the results and metadata of canine, feline, and equine respiratory PCR panel assays performed at the New York State Animal Health Diagnostic Center and inform veterinary diagnostic sample submission. Unassigned: This retrospective study reviewed laboratory data from routine sample submissions to the Animal Health Diagnostic Center for canine, feline, and equine respiratory PCR panels from January 1 through December 31, 2023. Associations were compared between variables using χ2 tests of independence or Fisher exact tests. Unassigned: A total of 1,902 canine, feline, and equine resp...
Bain ME, Alsop EJ, Knox CA, Tweedie MA, Knottenbelt DC.Mycobacterium ulcerans infection in horses is under-reported. Objective: To document the successful multimodal treatment of M. ulcerans and highlight the need for further investigation due to the zoonotic nature of M. ulcerans with its related potential public health concerns. Methods: Case report CASE DESCRIPTION: A 14-year-old gelding in the Southeastern region of Australia was diagnosed with M. ulcerans infection, initially presenting as a non-healing wound of the right flank progressing to extensive necrotic ulceration. Ziehl-Neelsen and Wade-Fite stained incisional biopsies revealed large...
Uprety T, Swan M, Kennedy L, Bryant U, Cassone L, Loynachan A, Janes J, Evely MM, Calvaruso FC, Quick M, Morgan J, Abdelrazek S, Lahmers K, Carter C....Clostridium piliforme is an obligate intracellular filamentous bacterium that causes Tyzzer disease (TD) in many animals. The disease manifests as severe, multifocal necrotizing hepatitis, with a high fatality rate in foals. Through retrospective investigation, we detected C. piliforme in 43 equine necropsy cases from 2012 to 2024. Positive cases were diagnosed from February to July, peaking in May. The age of affected foals ranged from 4 days to 2 months. Histologically, all cases had necrotizing hepatitis with multifocal, coalescing pinpoint, tan or reddish foci. Since only a partial 16S rRN...
Kaštovská E, Mastný J, Choma M, Čapek P, Jirků M, Bitomský M, Konvička M.Based on a growing understanding of the role of wild megafauna in the functioning of natural ecosystems, trophic rewilding by large herbivores is increasingly used as a nature-based solution to mitigate biodiversity loss and climate change in Europe and beyond. Despite the growing interest in implementing nature-based approaches to restore key non-productive ecosystem services, there is relatively little data available to assess the benefits and risks of rewilding projects. We therefore investigated the effects of year-round grazing by large ungulates on plant biomass characteristics and their...
Suganuma K, Narantsatsral S, Battur B, Yamasaki S, Otgonsuren D, Musinguzi SP, Davaasuren B, Battsetseg B, Inoue N.Trypanosoma equiperdum causes dourine via sexual transmission in Equidae. T. equiperdum is classified under the subgenus Trypanozoon along with the T. brucei sspp. and T. evansi; however, the species classification of Trypanozoon remains a controversial topic due to the limited number of T. equiperdum reference strains. In addition, it is possible that some were misclassified T. evansi strains. Thus, there is a strong need for a new T. equiperdum strain directly isolated from the genital mucosa of a horse with a clinically- and parasitologically-confirmed dourine infection. Trypanosomes isolat...
Hanafy RA, Lanjekar VB, Dhakephalkar PK, Callaghan TM, Dagar SS, Griffith GW, Elshahed MS, Youssef NH.We isolated and characterized 65 anaerobic gut fungal (AGF; Neocallimastigomycota) strains from fecal samples of five wild (W, axis deer, white-tailed deer, Boer goat, mouflon, and Nilgiri tahr), one zoo-housed (Z, zebra), and three domesticated (D, horse, sheep, and goat) herbivores in the US states of Texas (TX) and Oklahoma (OK), Wales (WA), and the Indian states of Kerala (KE) and Haryana (HA). Phylogenetic assessment using the D1-D2 regions of the large subunit (28S) rDNA and internal transcribed spacer 1 (ITS1) identified seven monophyletic clades that are distinct from all curren...
Castanheira C, Balaskas P, Falls C, Ashraf-Kharaz Y, Clegg P, Burke K, Fang Y, Dyer P, Welting TJM, Peffers MJ.Osteoarthritis remains one of the greatest causes of morbidity and mortality in the equine population. The inability to detect pre-clinical changes in osteoarthritis has been a significant impediment to the development of effective therapies against this disease. Synovial fluid represents a potential source of disease-specific small non-coding RNAs (sncRNAs) that could aid in the understanding of the pathogenesis of osteoarthritis. We hypothesised that early stages of osteoarthritis would alter the expression of sncRNAs, facilitating the understanding of the underlying pathogenesis and potenti...
Hong CB, Donahue JM, Giles RC, Petrites-Murphy MB, Poonacha KB, Roberts AW, Smith BJ, Tramontin RR, Tuttle PA, Swerczek TW.Placentas from aborted, stillborn, and premature foals were examined during the 1988 and 1989 foaling seasons, and 236 of 954 (24.7%) had placentitis. Microorganisms associated with placentitis were isolated or demonstrated from 162 of 236 (68.6%) placentitis cases. Leptospira spp. and a nocardioform actinomycete were 2 important, newly emerging bacteria associated with equine placentitis. Major pathogens identified in decreasing order were Streptococcus zooepidemicus, Leptospira spp., Escherichia coli, a nocardioform actinomycete, fungi, Pseudomonas aeruginosa, Streptococcus equisimilis, Ente...
Xia Y, Qin S, Shen Y.In this study, we isolated four Weissella confusa strains from the healthy horse feces to test their potential as equine probiotics. The identification and characteristics of these isolates were determined as per standard methods. Resistance and susceptibility of the isolated strains were tested to low pHs, different heat treatments, commonly used antibiotics and against the pathogenic strains of Salmonella, Pasteurella, Staphylococcus aureus, and Escherichia coli. After 3 h cultural in different pH medium, the 4 strains still had a certain amount of survival above pH 3.0. WH2 and WH4 were s...
Schamberger GP, Diez-Gonzalez F.Escherichia coli strains were screened for their ability to inhibit E. coli O157:H7. An initial evaluation of 18 strains carrying previously characterized colicins determined that only colicin E7 inhibited all of the E. coli O157:H7 strains tested. A total of 540 strains that had recently been isolated from humans and nine different animal species (cats, cattle, chickens, deer, dogs, ducks, horses, pigs, and sheep) were tested by a flip-plating technique. Approximately 38% of these strains were found to inhibit noncolicinogenic E. coli K12 strains. The percentage of potentially colicinogenic E...
Charbonneau ARL, Forman OP, Cain AK, Newland G, Robinson C, Boursnell M, Parkhill J, Leigh JA, Maskell DJ, Waller AS.Utilising next generation sequencing to interrogate saturated bacterial mutant libraries provides unprecedented information for the assignment of genome-wide gene essentiality. Exposure of saturated mutant libraries to specific conditions and subsequent sequencing can be exploited to uncover gene essentiality relevant to the condition. Here we present a barcoded transposon directed insertion-site sequencing (TraDIS) system to define an essential gene list for Streptococcus equi subsp. equi, the causative agent of strangles in horses, for the first time. The gene essentiality data for this grou...
Hoet AE, Johnson A, Nava-Hoet RC, Bateman S, Hillier A, Dyce J, Gebreyes WA, Wittum TE.Concurrent to reports of zoonotic and nosocomial transmission of methicillin-resistant Staphylococcus aureus (MRSA) in veterinary settings, recent evidence indicates that the environment in veterinary hospitals may be a potential source of MRSA. The present report is a cross-sectional study to determine the prevalence of MRSA on specific human and animal contact surfaces at a large veterinary hospital during a nonoutbreak period. A total of 156 samples were collected using Swiffers(®) or premoistened swabs from the small animal, equine, and food animal sections. MRSA was isolated and identifi...
Alber J, El-Sayed A, Lämmler C, Hassan AA, Weiss R, Zschöck M.The closely related streptococcal species Streptococcus equi subsp. zooepidemicus and S. equi subsp. equi were identified by polymerase chain reaction using oligonucleotide primers designed according to species-specific parts of the superoxide dismutase A encoding gene sodA. A further differentiation of both subspecies could be performed by amplification of the genes seeH and seeI encoding the exotoxins SeeH and SeeI, respectively, which could be detected for S. equi subsp. equi but not for S. equi subsp. zooepidemicus. A further simplification of the identification and differentiation of both...
Goodson J, Tyznik WJ, Cline JH, Dehority BA.Microbial numbers, pH, fluid volume, and turnover rate in the pony cecum were measured during an abrupt change from an all-forage to an all-concentrate diet, both fed at maintenance energy levels. Concentrate feeding resulted in increased (P less than 0.01) numbers of total viable anaerobic bacteria. The numbers of organisms growing on selective starch medium increased (P less than 0.01) when concentrate was fed, while numbers on xylan and pectin media decreased (P less than 0.025). Seven days after the diet change to concentrate, the number of bacteria growing on lactate medium increased (P l...
Young R, Taylor JE, Kurioka A, Becker M, Louis EJ, Rudenko G.African trypanosomes (including Trypanosoma brucei) are unicellular parasites which multiply in the mammalian bloodstream. T. brucei has about twenty telomeric bloodstream form Variant Surface Glycoprotein (VSG) expression sites (BESs), of which one is expressed at a time in a mutually exclusive fashion. BESs are polycistronic transcription units, containing a variety of families of expression site associated genes (ESAGs) in addition to the telomeric VSG. These polymorphic ESAG families are thought to play a role in parasite-host adaptation, and it has been proposed that ESAG diversity might ...
Kim MC, Lee SW, Ryu DY, Cui FJ, Bhak J, Kim Y.The role of microRNAs (miRNAs) as a post-transcriptional gene regulator has been elucidated in a broad range of organisms including domestic animals. Characterization of miRNAs in normal tissues is an important step to investigate the functions of miRNAs in various physiological and pathological conditions. Using Illumina Next Generation Sequencing (NGS) technology, we identified a total of 292 known and 329 novel miRNAs in normal horse tissues including skeletal muscle, colon and liver. Distinct sets of miRNAs were differentially expressed in a tissue-specific manner. The miRNA genes were dis...
Walther B, Klein KS, Barton AK, Semmler T, Huber C, Merle R, Tedin K, Mitrach F, Lübke-Becker A, Gehlen H.Continuing introduction of multi-drug resistant, zoonotic pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) in horse clinics challenges the biosafety of employees and animal patients. This study was aimed to determine the occurrence of mobile genetic elements facilitating survival in the early stages of invasive infection in different host species, including humans and horses, in MRSA carried by equine patients admitted to a large horse clinic. A total of 341 equine patients were investigated for carriage of MRSA by hygiene screening directly at hospital admission. MRSA were...
Burton S, Reid-Smith R, McClure JT, Weese JS.Methicillin-resistant Staphylococcus aureus (MRSA) colonization was not identified in any of 497 horses from Atlantic Canada. Methicillin-susceptible S. aureus (MSSA) was isolated from a subsample of 19/242 (7.9%) horses. Colonization with MSSA is relatively common in healthy horses in Atlantic Canada, but MRSA is currently rare or absent. Colonisation par Staphylococus aureus de chevaux en santé sur la côte atlantique du Canada. La colonisation par Staphylococus aureus résistant à la méthicilline (SARM) n’a été identifiée sur aucun des 497 chevaux testés provenant de la côte atlan...
Damborg P, Marskar P, Baptiste KE, Guardabassi L.The objective of this longitudinal study was to investigate the occurrence and genetic background of faecal Escherichia coli resistant to cefotaxime (CTX) in horses receiving broad-spectrum antimicrobial prophylaxis after admission to a veterinary teaching hospital. The ten horses enrolled in the study were treated with cefquinome either alone (n=4) or in combination with metronidazole (n=3) or other antimicrobial agents (n=3). CTX-resistant coliforms in faeces collected before, during and after treatment were quantified on selective MacConkey agar supplemented with CTX, and a colony isolated ...
Tajima M, Nakajima H, Ito Y.Equine infectious anemia (EIA) virus was observed in thin sections of infected cultured horse leukocytes by electron microscopy. The virus particles had a spherical shape and were between 80 and 120 nm in diameter. Most of them contained an electron-dense nucleoid 40 to 60 nm in diameter. They were observed to form by a process of budding from the plasma membrane and appeared to have thin surface projections. The particles described were not detected in uninfected cultured cells, and their appearance could be prevented by adding EIA immune serum to the inoculum. The implications of these findi...
Björnsdóttir S, Harris SR, Svansson V, Gunnarsson E, Sigurðardóttir ÓG, Gammeljord K, Steward KF, Newton JR, Robinson C, Charbonneau ARL....Iceland is free of the major infectious diseases of horses. However, in 2010 an epidemic of respiratory disease of unknown cause spread through the country's native horse population of 77,000. Microbiological investigations ruled out known viral agents but identified the opportunistic pathogen subsp. () in diseased animals. We sequenced the genomes of 257 isolates of to differentiate epidemic from endemic strains. We found that although multiple endemic clones of were present, one particular clone, sequence type 209 (ST209), was likely to have been responsible for the epidemic. Concurrent ...
Donadeu FX, Schauer SN.Relatively little is known about the physiological roles of microRNAs (miRNAs) during follicular development. Previous evidence from in vitro studies suggests specific roles for a subset of miRNAs, including miR-21, miR-23a, miR-145, miR-503, miR-224, miR-383, miR-378, miR-132, and miR-212, in regulating ovarian follicle development. The objective of this study was to gain insight on the involvement of these miRNAs during follicle maturation. Follicular fluid was aspirated from dominant follicles (>32 mm) during the ovulatory season (July to October) and the anovulatory season (January to M...
Riesenberg A, Feßler AT, Erol E, Prenger-Berninghoff E, Stamm I, Böse R, Heusinger A, Klarmann D, Werckenthin C, Schwarz S.The aim of this study was to determine the MICs of 32 antimicrobial agents for 200 isolates of Rhodococcus equi of animal origin by applying a recently described broth microdilution protocol, and to investigate isolates with distinctly elevated rifampicin MICs for the genetic basis of rifampicin resistance. Methods: The study included 200 R. equi isolates, including 160 isolates from horses and 40 isolates from other animal sources, from the USA and Europe. MIC testing of 32 antimicrobial agents or combinations thereof followed a recently published protocol. A novel PCR protocol for the joint ...
Halbert ND, Reitzel RA, Martens RJ, Cohen ND.To evaluate sensitivity and specificity of a multiplex polymerase chain reaction (PCR) assay for simultaneous detection of Rhodococcus equi and differentiation of strains that contain the virulence-associated gene (vapA) from strains that do not. Methods: 187 isolates of R equi from equine and nonequine tissue and environmental specimens and 27 isolates of bacterial species genetically or morphologically similar to R equi. Methods: The multiplex PCR assay included 3 gene targets: a universal 311-bp bacterial 16S ribosomal RNA amplicon (positive internal control), a 959-bp R equi-specific targe...
Renshaw RW, Glaser AL, Van Campen H, Weiland F, Dubovi EJ.A virus that could not be identified as a previously known equine virus was isolated from the mononuclear cells of a horse. Electron microscopy revealed enveloped virions with nucleocapsid structures characteristic of viruses in the Paramyxoviridae family. The virus failed to hemabsorb chicken or guinea pig red blood cells and lacked neuraminidase activity. Two viral genes were isolated from a cDNA expression library. Multiple sequence alignments of one gene indicated an average identity of 45% as compared to Morbillivirus N protein sequences. A weaker relationship was found with Tupaia paramy...
Tripathi VN, Harding WC, Willingham-Lane JM, Hondalus MK.Rhodococcus equi is a facultative intracellular, Gram-positive, soilborne actinomycete which can cause severe pyogranulomatous pneumonia with abscessation in young horses (foals) and in immunocompromised people, such as persons with AIDS. All strains of R. equi isolated from foals and approximately a third isolated from humans contain a large, ~81-kb plasmid which is essential for the intramacrophage growth of the organism and for virulence in foals and murine in vivo model systems. We found that the entire virulence plasmid could be transferred from plasmid-containing strains of R. equi (dono...
Kecerova Z, Cizek A, Nyc O, Krutova M.Clostridium difficile has been recovered from the faeces of several animal species as well as horses. Between April 2015 and October 2016, 213 samples of faeces from non-hospitalized (n = 138) and hospitalized horses (n = 75) were investigated and eighteen C. difficile isolates were cultured using an enrichment method. Sixteen C. difficile positive samples were identified from hospitalised horses (p < 0.01). Molecular typing revealed seven ribotypes and sequence types (RT033/ST11 n = 8, 44.4%; RT081/ST9 n = 4, 22.2%; RT009/ST3 n = 2, 11.1%; RT003/ST12 n = 1, 5.6%;...
Destrez A, Grimm P, Julliand V.The bidirectional communication between the central and the enteric nervous system named the gut-brain axis has been widely recognized. The gut microbiota has been implicated in a variety of stress-related conditions including anxiety, depression and irritable bowel syndrome based on rodent studies or correlative analysis in human patients. The aim of the present study was to investigate to what extent changes in behavior during stressful events and in the microbial composition of the colonic ecosystem were associated in horses. The microbiota alterations were induced by a change from a high-f...
Marsh PS, Palmer JE.To assess microorganisms isolated from blood specimens obtained from critically ill neonatal foals and to evaluate their antimicrobial susceptibility patterns. Methods: Retrospective study. Methods: 543 neonatal foals. Methods: Medical records of foals that were < 1 month old and were admitted to a referral neonatal intensive care unit were reviewed for results of bacteriologic culture of blood and antimicrobial susceptibility patterns. Results: At least 1 microorganism was isolated from 155 of 543 (28.5%) foals. Escherichia coli was the most commonly isolated bacterium. A single gram-posit...
Garrett LA, Brown R, Poxton IR.This study compares quantitatively the microbiota of the gastrointestinal tract of healthy horses with that of horses with equine grass sickness (EGS). Faecal and ileal samples were cultured quantitatively on selective and non-selective media. Confirmed anaerobes were identified to species level. Overall faecal counts gave a ratio of aerobes:anaerobes of approximately 1:1. However, the mean counts in healthy horses of 4.4x10(8) aerobes:3.7x10(8) anaerobes per gram wet weight were different from counts in EGS (means were 10-100-fold higher), with statistically significant differences for the an...
Pezzanite LM, Chow L, Johnson V, Griffenhagen GM, Goodrich L, Dow S.To evaluate effects of Toll-like and nucleotide-binding oligomerization domain (NOD)-like receptor (TLR, NLR) ligand stimulation of equine mesenchymal stromal cells (MSCs) on antibacterial and immunomodulatory properties in vitro. Methods: Controlled laboratory study. Methods: Equine bone-marrow-derived MSCs (three horses). Methods: MSCs were stimulated with TLR (polyinosinic:polycytidylic acid [pIC] and lipopolysaccharide [LPS]) and NLR agonists (γ-d-Glu-mDAP [IE-DAP]) for 2 h, and plated at 1 × 105 cells/well 24 h. MSC-conditioned media (MSC-CM) were collected and assessed for antimicr...
Wunderlich G, Bull M, Ross T, Rose M, Chapman B.The equine gastrointestinal tract is a self-sufficient fermentation system, housing a complex microbial consortium that acts synergistically and independently to break down complex lignocellulolytic material that enters the equine gut. Despite being strict herbivores, equids such as horses and zebras lack the diversity of enzymes needed to completely break down plant tissue, instead relying on their resident microbes to carry out fibrolysis to yield vital energy sources such as short chain fatty acids. The bulk of equine digestion occurs in the large intestine, where digesta is fermented for 3...
Research in microbiologyJanuary 14, 2016
Volume 167, Issue 4 313-324 doi: 10.1016/j.resmic.2016.01.001
Deredjian A, Alliot N, Blanchard L, Brothier E, Anane M, Cambier P, Jolivet C, Khelil MN, Nazaret S, Saby N, Thioulouse J, Favre-Bonté S.The occurrence of Stenotrophomonas maltophilia was monitored in organic amendments and agricultural soils from various sites in France and Tunisia. S. maltophilia was detected in horse and bovine manures, and its abundance ranged from 0.294 (±0.509) × 10(3) to 880 (±33.4) × 10(3) CFU (g drywt)(-1) of sample. S. maltophilia was recovered from most tested soil samples (104/124). Its abundance varied from 0.33 (±0.52) to 414 (±50) × 10(3) CFU (g drywt)(-1) of soil and was not related to soil characteristics. Antibiotic resistance properties of a set of environmental strains were ...