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.
Lin J, Jing H, Wang J, Lucien-Cabaraux JF, Yang K, Liu W, Li X.The nutritional benefits of mare milk are attracting increasing consumer interest. Limited availability due to low yield poses a challenge for widespread adoption. Although lysine and threonine are often used to enhance protein synthesis and muscle mass in horses, their impact on mare milk yield and nutrient composition remains underexplored. This study investigated the effects of lysine and threonine supplementation on 24 healthy Yili mares, mares at day 30 of lactation, over a 120-day period. The mares were divided into control and three experimental groups (six mares each) under pure grazin...
Pusterla N, Lawton K, Barnum S.In populations of healthy show horses, the subclinical transmission and circulation of respiratory pathogens can lead to disease outbreaks. Due to recent outbreaks of equine herpesvirus-1 myeloencephalopathy (EHM) in the USA and Europe, many show organizers have instituted various biosecurity protocols such as individual horse testing, monitoring for early clinical disease and increasing hygiene and cleanliness protocols. The aim of this study was to determine the accuracy of detecting EHV-1 in the various environmental samples collected from the stalls of subclinical shedders. Four healthy ad...
Bishop RC, Migliorisi A, Holmes JR, Kemper AM, Band M, Austin S, Aldridge B, Wilkins PA.Understanding normal microbial populations within areas of the respiratory tract is essential, as variable regional conditions create different niches for microbial flora, and proliferation of commensal microbes likely contributes to clinical respiratory disease. The objective was to describe microbial population variability between respiratory tract locations in healthy horses. Samples were collected from four healthy adult horses by nasopharyngeal lavage (NPL), transtracheal aspirate (TTA), and bronchoalveolar lavage (BAL) of six distinct regions within the lung. Full-length 16S ribosomal DN...
Behroozi M, Graïc JM, Gerussi T.Diffusion-weighted Imaging (DWI) is an effective and state-of-the-art neuroimaging method that non-invasively reveals the microstructure and connectivity of tissues. Recently, novel applications of the DWI technique in studying large brains through imaging enabled researchers to gain insights into the complex neural architecture in different species such as those of (e.g., horses and rhinos), (e.g., bovids, swines, and cetaceans), and (e.g., felids, canids, and pinnipeds). Classical tract-tracing methods are usually considered unsuitable for ethical and practical reasons, in large animals...
Heil BA, van Heule M, Thompson SK, Kearns TA, Beckers KF, Oberhaus EL, King G, Daels P, Dini P, Sones JL.The equine uterus is highly interrogated during estrus prior to breeding and establishing pregnancy. Many studies in mares have been performed during estrus under the influence of high estrogen concentrations, including the equine estrual microbiome. To date, it is unknown how the uterine microbiome of the mare is influenced by cyclicity; while, the equine vaginal microbiome is stable throughout the estrous cycle. We hypothesized that differences would exist between the equine endometrial microbiome of mares in estrus and anestrus. The aim of this study was two-fold: to characterize the reside...
Strompfová V, Štempelová L.Characterization of microbiota structure on the skin of healthy horses is important for further development of modulation strategies to ensure optimal bacterial composition for physiological processes. This requirement is also supported by the relatively high incidence of dermatological diseases in horses and thus the need to manage them therapeutically. The taxonomic analysis of skin samples (n = 30) from five different body parts of clinically healthy Shetlands ponies females (neck, back, abdomen, pastern, muzzle) kept under homogeneous conditions (in open stalls with paddock, feed with ...
Nakajima K, Kasuya K, Senba H, Tagami K, Kinoshita Y, Niwa H.Strangles is a globally widespread, commonly diagnosed and important infectious disease of equids caused by Streptococcus equi subsp. equi. We performed whole genome sequencing of 19 S. equi isolates collected from imported horses at the Japanese border. Of these isolates, 15 isolates were obtained from clinical cases and 4 were from subclinical cases. The 19 isolates were grouped into 3 Bayesian analysis of population structure (BAPS) groups by the core genome single nucleotide polymorphism analysis corresponding to exporting country, SeM typing, or exporter of the horses. The 19 isolates pos...
Wester RJ, Baillie LL, McCarthy GC, Keever CC, Jeffery LE, Adams PJ.Free Fecal Liquid (FFL), also termed Fecal Water Syndrome (FWS), is an ailment in horses characterized by variable solid and liquid (water) phases at defecation. The liquid phase can be excreted before, during, or after the solid defecation phase. While the underlying causes of FFL are unknown, hindgut dysbiosis is suggested to be associated with FFL. Three European studies investigated dysbiosis in horses with FFL using 16S rRNA sequencing and reported results that conflicted between each other. In the present study, we also used 16S rRNA sequencing to study the fecal microbial composition in...
Baraille M, Buttet M, Grimm P, Milojevic V, Julliand S, Julliand V.Horse owners and veterinarians report that from the age of 15, their horses can lose body condition and be more susceptible to diseases. Large intestinal microbiome changes may be involved. Indeed, microbiota is crucial for maintaining the condition and health of herbivores by converting fibres into nutrients. This study aimed to compare the faecal microbiome in horses aged from 6 to 30 years old (yo), living in the same environment and consuming the same diet, in order to assess whether the parameters changed linearly with age and whether there was a pivotal age category. Fifty horses were se...
Kawaida MY, Maas KR, Moore TE, Reiter AS, Tillquist NM, Reed SA.To determine the effects of astaxanthin (ASTX) supplementation on the equine gut microbiota during a deconditioning-reconditioning cycle, 12 polo ponies were assigned to a control (CON; n = 6) or supplemented (ASTX; 75 mg ASTX daily orally; n = 6) group. All horses underwent a 16-week deconditioning period, with no forced exercise, followed by a 16-week reconditioning program where physical activity gradually increased. Fecal samples were obtained at the beginning of the study (Baseline), after deconditioning (PostDecon), after reconditioning (PostRecon), and 16 weeks after the ces...
Tong P, Pan J, Dang Y, Yang E, Jia C, Duan R, Tian S, Palidan N, Kuang L, Wang C, Lu G, Xie J.Equine herpesvirus type 1 (EHV-1) is commonly associated with horse abortion. Currently, there are no reported cases of abortion resulting from EHV-1 infection in donkeys. This was the first survey-based study of Chinese donkeys. The presence of EHV-1 was identified by PCR. This survey was conducted in Chabuchar County, North Xinjiang, China, in 2020. A donkey EHV-1 strain (Chabuchar/2020) was successfully isolated in MDBK cells. Seventy-two of 100 donkey sera were able to neutralize the isolated EHV-1. Moreover, the ORF33 sequence of the donkey-origin EHV-1 Chabuchar/2020 strain showed high l...
Ramos-Vázquez JR, Sánchez-Montes S, Esparza-González SC, Romero-Salas D, Pardio-Sedas V, Estrada-Coates AT, Alva-Trujillo M, Ballados-González GG....Leptospirosis is an infectious disease with a worldwide distribution, which represents a major challenge in animal production across developing countries, mainly in tropical areas. Horses are particularly susceptible to the disease, presenting manifestations ranging from subclinical to the development of uveitis that compromises the visual health of the animals. In recent years, serological studies have been carried out in equid populations from America, demonstrating high exposure. For this reason, the aim of this study was to demonstrate microbiologically and molecularly the presence of the ...
Zečević I, Picardeau M, Vince S, Hađina S, Perharić M, Štritof Z, Stevanović V, Benvin I, Turk N, Lohman Janković I, Habuš J.Leptospirosis is one of the most common zoonotic infections and a major problem in terms of both veterinary medicine and public health. However, the disease is under-recognised and under-diagnosed worldwide, particularly in horses. Clinical leptospirosis in horses is mainly associated with recurrent uveitis (ERU), which has recently been studied more intensively, and reproductive disorders, the epidemiology of which is still relatively poorly understood. To enhance our comprehension of abortions caused by leptospirosis in horses and to identify the causative strains, a serological study was ca...
Raspa F, Chessa S, Bergero D, Sacchi P, Ferrocino I, Cocolin L, Corvaglia MR, Moretti R, Cavallini D, Valle E.Diet is one of the main factors influencing the intestinal microbiota in horses, yet a systematic characterization of the microbiota along the length of the digestive tract in clinically healthy horses, homogenous for age and breed and receiving a specific diet is lacking. Unassigned: The study used 16S rRNA amplicon sequencing to characterize the microbiota of the intestinal tracts of 19 healthy Bardigiano horses of 14.3 ± 0.7 months of age fed one of two diets. Nine horses received a high-starch diet (HS), and ten horses received a high-fiber diet (HF). After 129 days, the horse...
Mady EA, Osuga H, Toyama H, El-Husseiny HM, Inoue R, Murase H, Yamamoto Y, Nagaoka K.The gut microbiota (GM) is essential for mammalian health. Although the association between infant GM and breast milk (BM) composition has been well established in humans, such a relationship has not been investigated in horses. Hence, this study was conducted to analyze the GM formation of foals during lactation and determine the presence of low-molecular-weight metabolites in mares' BM and their role in shaping foals' GM. The fecal and BM samples from six pairs of foals and mares were subjected to 16S ribosomal RNA metagenomic and metabolomic analyses, respectively. The composition of foal G...
Green de Freitas M, Gonçalves Lino Borges D, Henrique Conde M, Takemi Muchon Nakatani M, Francieli Tutija J, Fuzaro Scaléa GO, Reckziegel GH....The aim of the present study was to validate methods of stool sample conservation for the egg hatch test (EHT). This study involved the use of a bovine naturally infected predominantly by Cooperia spp. and one equine naturally infected predominantly by cyathostomins characterized as susceptible to benzimidazoles in the EHT. Fecal samples were submitted to three treatments: aerobic methods (anaerobic storage in plastic bottles, anaerobic storage in vacuum-sealed bags or aerobic storage in plastic bags), under two temperature conditions (room temperature and refrigeration) analyzed at four diffe...
Ducrocq M, Kamus L, Richard H, Beauchamp G, Janvier V, Laverty S.Stifle osteoarthritis (OA) lesions are most common in the medial femorotibial (MFT) compartment. Their characterisation and mapping will inform equine veterinarians towards an accurate diagnosis of OA. Objective: Investigate and map micro-CT (μCT) changes in the hyaline articular cartilage (HAC) in the medial femoral condyle (MFC) and medial tibial plateau (MTP). Methods: Ex vivo cadaveric. Methods: Stifles (n = 7 OA and 17 control [CO]) were retrieved from a tissue bank. The MFC and MFT were imaged with μCT. Regions of interest (ROIs) were cranial (MFCcr; MTPcr) and caudal (MFCca; MTPca...
Sun J, Xu X, Gao S, Pan Q, Liu Z, Huang Y, Lian Y.Prevotella heparinolytica is a Gram-negative bacterium that is commonly found in the oral, intestinal, and urinary tracts. It has been extensively studied in lower respiratory tract infections in horses, which has heparinolytic activity and can secrete heparinase and further induces virulence factors in cells and causes disease. However, no such cases have been reported in humans. Methods: A 58-year-old male patient from China presented to the respiratory clinic in Suzhou with a productive cough producing white sputum for 20 days and fever for 3 days. Prior to this visit, a chest computed to...
Tuniyazi M, Tang R, Hu X, Fu Y, Zhang N.Diarrhea is a common gastrointestinal disorder in horses, with diet-induced diarrhea being an emerging challenge. This study aimed to investigate the gut microbiota differences in healthy and diet-induced diarrheic horses and evaluate the effectiveness of fecal microbiota transplantation (FMT) and carbonate buffer mixture (CBM) as potential therapeutic approaches. Twenty healthy horses were included in the study, with four groups: Control, Diarrhea, CBM, and FMT. Diarrhea was induced using oligofructose, and fecal samples were collected for microbiota analysis. FMT and CBM treatments were admi...
Emiru AY, Regassa F, Endebu Duguma B, Kassaye A, Desyebelew B.Effective therapy for many infections is becoming difficult due to the evolutionary development of drug resistance, and hence, the development of alternative treatment options mainly from herbs is crucial. The objective of this study was to investigate the antibacterial effects of ethanol extracts of stem bark, leaves and roots of Combretum molle against Streptococcus equi isolated from clinical cases of strangles using in vitro tests. Methods: Plant extraction was performed using a maceration technique with 80% ethanol. The mean zone of inhibition was determined using the agar well diffusion ...
Muroni G, Serra E, Biggio GP, Sanna D, Cherchi R, Taras A, Appino S, Foxi C, Masala G, Loi F, Chisu V.The members of the family are important pathogens that infect a wide range of vertebrate hosts, including humans. Among them, , historically considered as an avian agent, has recently been identified in livestock, primarily sheep and cattle, but also in horses, with the infection being linked to reproductive disorders, such as abortion, absorption of embryos, stillbirth, and the birth of weak foals. Much less is known about chlamydial infections in the Sardinian equine population. This study aimed to identify the chlamydial diversity in genital samples from asymptomatic Sardinian horses. Howe...
Hellman S, Martin F, Tydén E, Sellin ME, Norman A, Hjertner B, Svedberg P, Fossum C.Stem cell-derived organoid cultures have emerged as attractive experimental models for infection biology research regarding various types of gastro-intestinal pathogens and host species. However, the large size of infectious nematode larvae and the closed structure of 3-dimensional organoids often hinder studies of the natural route of infection. To enable easy administration to the apical surface of the epithelium, organoids from the equine small intestine, i.e. enteroids, were used in the present study to establish epithelial monolayer cultures. These monolayers were functionally tested by s...
Higgins C, Cohen ND, Slovis N, Boersma M, Gaonkar PP, Golden DR, Huber L.Antimicrobial residues excreted in the environment following antimicrobial treatment enhance resistant microbial communities in the environment and have long-term effects on the selection and maintenance of antimicrobial resistance genes (AMRGs). In this study, we focused on understanding the impact of antimicrobial use on antimicrobial residue pollution and antimicrobial resistance (AMR) in the environment of horse-breeding farms. is an ideal microbe to study these associations because it lives naturally in the soil, exchanges AMRGs with other bacteria in the environment, and can cause disea...
Hamad MH, Islam SI, Jitsamai W, Chinkangsadarn T, Naraporn D, Ouisuwan S, Taweethavonsawat P.The indiscriminate use of anthelmintics to control parasitic nematodes in horses has led to the emergence of anthelmintic resistance worldwide. However, there are no data available on using ivermectin for treating strongyle infections within domesticated horses in Thailand. Therefore, this study aimed to use the fecal egg count reduction (FECR) test to determine the strongylid egg reappearance period (ERP). Additionally, the nemabiome metabarcoding approach is incorporated to study patterns of strongyle species infection following ivermectin treatment. The study results indicate that, although...
Girma T, Chala G, Mekibib B.Epizootic lymphangitis is an infectious and chronically debilitating disease of the equines. Histoplasma capsulatum var. farciminosum, a thermally dimorphic fungi, is the causative agent for the disease. In Ethiopia, the disease significantly affects carthorses, posing threats to animal welfare, and resulting in substantial economic losses. Limited availability of widely accessible antifungals in addition to the chronic nature of the disease is the major challenge against management of epizootic lymphangitis. This study aimed to assess the in vitro efficacy of specific local medicinal plant ex...
Mirabal B, Andrade BS, Souza SPA, Oliveira IBDS, Melo TS, Barbosa FS, Jaiswal AK, Seyffert N, Portela RW, Soares SC, Azevedo V, Meyer R, Tiwari S....Equine strangles is a prevalent disease that affects the upper respiratory in horses and is caused by the Gram-positive bacterium . In addition to strangles, other clinical conditions are caused by the two subspecies, and , which present relevant zoonotic potential. Treatment of infections caused by has become challenging due to the worldwide spreading of infected horses and the unavailability of effective therapeutics and vaccines. Penicillin treatment is often recommended, but multidrug resistance issues arised. We explored the whole genome sequence of 18 isolates to identify candidate p...
Cain JL, Norris JK, Swan MP, Nielsen MK.The microbiome plays an important role in health, where changes in microbiota composition can have significant downstream effects within the host, and host-microbiota relationships can be exploited to affect health outcomes. Parasitic helminths affect animals globally, but an exploration of their microbiota has been limited, despite the development of anti-Wolbachia drugs to help control infections with some filarial nematodes. The equine ascarids, Parascaris spp., are considered the most pathogenic nematodes affecting juvenile horses and are also the only ascarid parasite to have developed wi...
Takai S, Suzuki Y, Sasaki Y, Kakuda T, Ribeiro MG, Makrai L, Witkowski L, Cohen N, Sekizaki T.Virulent Rhodococcus equi strains expressing virulence-associated 15-17 kDa protein (VapA) and having a large virulence plasmid (pVAPA) of 85-90 kb containing vapA gene are pathogenic for horses. In the last two decades, following pVAPA, two host-associated virulence plasmid types of R. equi have been discovered: a circular plasmid, pVAPB, associated with porcine isolates in 1995, and a recently detected linear plasmid, pVAPN, related to bovine and caprine isolates. Molecular epidemiological studies of R. equi infection in foals on horse-breeding farms in Japan and many countries around the ...
Grönthal TSC, Lehto AK, Aarnio SS, Eskola EK, Aimo-Koivisto EM, Karlsson T, Koskinen HI, Barkoff AM, He Q, Lienemann T, Rimhanen-Finne R, Mykkänen A.Corynebacterium diphtheriae and Corynebacterium ulcerans, when producing toxin, are the cause of diphtheria, a potentially life-threatening illness in humans. Horses (Equus ferus caballus) are known to be susceptible to infection that may manifest clinically on rare occasions. In late 2021 and early 2022, specimens from five horses suffering from pastern dermatitis were cultured at the Laboratory of Clinical Microbiology at the Faculty of Veterinary Medicine, University of Helsinki, Finland. C. diphtheriae and/or C. ulcerans were recovered from all of these. This study aimed to (1) analyse the...
Samuelson DA, Andresen TL, Gwin RM.Conjunctival swab specimens were obtained from both eyes of 43 horses, 25 cows, 50 dogs, and 25 cats without keratitis or other ophthalmologic problems. Fungi were isolated from 95% of the horses, 100% of the cows, 22% of the dogs, and 40% of the cats. Aspergillus spp were isolated from 56% of the horses, 12% of the cows, 8% of the cats, and none of the dogs. Penicillium spp and Cladosporium spp were isolated ubiquitously. Collectively, 28 species from 209 isolants were identified.
Hébert L, Moumen B, Duquesne F, Breuil MF, Laugier C, Batto JM, Renault P, Petry S.Taylorella equigenitalis is the causative agent of contagious equine metritis (CEM), a sexually transmitted infection of horses. We herein report the genome sequence of T. equigenitalis strain MCE9, isolated in 2005 from the urethral fossa of a 4-year-old stallion in France.
Takai S, Takeda K, Nakano Y, Karasawa T, Furugoori J, Sasaki Y, Tsubaki S, Higuchi T, Anzai T, Wada R, Kamada M.To investigate the emergence of rifampin resistance in Rhodococcus equi strains isolated from foals and their environment in Japan, we compared the in vitro antimicrobial susceptibilities to rifampin of 640 isolates from 64 infected foals and 98 soil isolates from their horse-breeding farms. As a control, 39 human isolates from patients with and without AIDS were also tested for susceptibility to rifampin. All of the isolates showed rifampin sensitivity, except isolates from one infected foal and two patients with AIDS that showed rifampin resistance. To investigate the emergence of rifampin-r...
Lwin KO, Matsui H.Comparative analysis of methanogen compositions in the feces of horse and pony was carried out by constructing the α -subunit of methyl coenzyme-M reductase (mcrA) gene and 16S ribosomal RNA gene (16S rRNA) clone libraries. The mcrA clone library analysis indicated that Methanomicrobiales was predominant in both horse and pony. Furthermore, most of the clones of the 16S rRNA gene library showed that Methanomicrobiales was also predominant in horse and pony, but the LIBSHUFF analysis showed that the horse and pony libraries were significantly different (P < 0.05). Most of operational taxono...
Lee S, Hwang S, Yu HJ, Oh D, Choi YJ, Kim MC, Kim Y, Ryu DY.MicroRNAs (miRNAs) in blood plasma are stable under high levels of ribonuclease activity and could function in tissue-to-tissue communication, suggesting that they may have distinctive structural characteristics compared with non-circulating miRNAs. In this study, the expression of miRNAs in horse plasma and their characteristic nucleotide composition were examined and compared with non-plasma miRNAs. Highly expressed plasma miRNA species were not part of the abundant group of miRNAs in non-plasma tissues, except for the eca-let-7 family. eca-miR-486-5p, -92a, and -21 were among the most abund...
Diab SS, Rodriguez-Bertos A, Uzal FA.Clostridium difficile is commonly associated with diarrhea and colitis in humans and other mammals, including horses. To this date, the epidemiologic, microbiologic, clinical, and diagnostic aspects of C. difficile-associated disease (CDAD) in horses have been thoroughly described. However, reports describing the enteric pathology of this disease in horses are limited. This study presents a comprehensive description of the pathologic characteristics of CDAD in 21 horses and discusses the criteria for the diagnosis of the disease. Case selection was based on C. difficile A/B toxins detection (e...
Moore RM, Schneider RK, Kowalski J, Bramlage LR, Mecklenburg LM, Kohn CW.Bacterial culture and susceptibility results were analysed from 233 horses with septic arthritis/tenosynovitis or osteomyelitis that developed after fracture repair. Antibiotics were deemed highly effective, effective or ineffective if > or = 85%, 70-84.9% or < 70% of the isolates were susceptible respectively. In total, 424 bacterial types were isolated; 386 were aerobic or facultative and 38 were anaerobic. Enterobacteriaceae (28.8%) were the most common bacterial group isolated, followed by non-beta-haemolytic streptococci (13.0%), coagulase-positive staphylococci (11.8%), beta-haemol...
Mapes S, Rhodes DM, Wilson WD, Leutenegger CM, Pusterla N.Fifty-five isolates of Escherichia coli from septicaemic neonatal foals were used to validate five real-time pcr assays targeting different known virulence factor genes: curli fibre (csgD), ferric hydroxamate uptake (fhuA), type 1A pilin (fimA), aerobactin (lutA) and yersiniabactin (fyuA). A pcr assay targeting a universal sequence of the bacterial 16S rrna gene served as quality control. The pcr assays showed good analytical specificity and sensitivity on the basis of sequencing the pcr products, their lack of cross-reactivity with non-E coli organisms, high amplification efficiency and a lim...
Al-Kass Z, Guo Y, Vinnere Pettersson O, Niazi A, Morrell JM.Bacteria colonize stallion semen during collection and processing which may cause disease in inseminated females or negatively affect sperm quality during storage prior to insemination. Antibiotics are added to semen extenders to control the growth of these bacteria but may induce antimicrobial resistance. Research into alternatives to antibiotics for this purpose requires knowledge of which bacteria are present in semen. Not all bacteria in semen, however, can be identified by conventional microbiological techniques. The objectives of the study were to: i) determine which bacteria are present...
Skive B, Rohde M, Molinari G, Braunstein TH, Bojesen AM. subsp. () is an opportunistic pathogen of several species including humans. is found on mucus membranes of healthy horses, but can cause acute and chronic endometritis. Recently was found able to reside in the endometrium for prolonged periods of time. Thus, we hypothesized that an intracellular phase may be part of the pathogenesis and investigated if was able to invade and survive inside epithelial cells. HEp-2 and HeLa cell lines were co-cultured with two strains (1-4a and S31A1) both originating from the uterus of mares suffering from endometritis. Cells were fixed at different time...
Smits K, Gansemans Y, Tilleman L, Van Nieuwerburgh F, Van De Velde M, Gerits I, Ververs C, Roels K, Govaere J, Peelman L, Deforce D, Van Soom A.The signal for maternal recognition of pregnancy (MRP) has still not been identified in the horse. High-throughput molecular biology at the embryo-maternal interface has substantially contributed to the knowledge on pathways affected during MRP, but an integrated study in which proteomics, transcriptomics and miRNA expression can be linked directly is currently lacking. The aim of this study was to provide such analysis. Endometrial biopsies, uterine fluid, embryonic tissues, and yolk sac fluid were collected 13 days after ovulation during pregnant and control cycles from the same mares. Micro...
Olivo G, Lucas TM, Borges AS, Silva RO, Lobato FC, Siqueira AK, da Silva Leite D, Brandão PE, Gregori F, de Oliveira-Filho JP, Takai S, Ribeiro MG.Diarrhea is a major clinical problem affecting foals up to 3 months of age. The aim of this study was to identify enteric microorganisms involved in monoinfections and coinfections and the associated virulence factors in healthy and diarrheic foals. Diarrheic (D) ( = 56) and nondiarrheic (ND) foals ( = 60) up to three months of age were studied. Fecal samples were analyzed for identification of infectious agents (microbiological culturing, molecular techniques, and microscopic analyses). (30% versus 25%), spp. (25% versus 7%), (25% versus 25%), type A (21% versus 10%), (20% versus 35%), ...
Harlow BE, Donley TM, Lawrence LM, Flythe MD.The goal was to determine the effect of starch source (corn, oats and wheat) and concentration on: (i) total amylolytic bacteria, Group D Gram-positive cocci (GPC), lactobacilli and lactate-utilizing bacteria, and (ii) fermentation by equine microbiota. Results: When faecal washed cell suspensions were incubated with any substrate amylolytics increased over time. However, at 24 h there were 10 and 1000-fold more amylolytics with corn than wheat or oats respectively. Predominant amylolytics isolated were Enterococcus faecalis (corn, wheat) and Streptococcus bovis (oats). GPC increased with any ...
Swyers KL, Burk AO, Hartsock TG, Ungerfeld EM, Shelton JL.A study was conducted to determine whether direct-fed microbials (DFM) could be used to increase digestibility and minimize the risk of acidosis associated with feeding an increase in the amount of starch fed to horses. Fifteen mature Thoroughbred geldings were randomly assigned to 1 of 3 treatments in a 3 x 3 Latin square design balanced for carryover effects. Within each 26-d period, horses were offered grass hay + low-starch concentrate (LS; 1.2 g of starch x kg of BW(-1) x meal(-1)) from d 1 to 13 and then were abruptly changed to hay + high-starch concentrate (HS; 2.4 g of starch.kg of BW...
Srivastava A, Singh BN, Deepak D, Rawat AK, Singh BR.The discovery of quorum-sensing (QS) systems regulating antibiotic resistance and virulence factors (VFs) has afforded a novel opportunity to prevent bacterial pathogenicity. Dietary molecules have been demonstrated to attenuate QS circuits of bacteria. But, to our knowledge, no study exploring the potential of colostrum hexasaccharide (CHS) in regulating QS systems has been published. In this study, we analyzed CHS for inhibiting QS signaling in Staphylococcus aureus. We isolated and characterized CHS from mare colostrum by high-performance thin-layer chromatography (HPTLC), reverse-phase hig...
Shnaiderman-Torban A, Navon-Venezia S, Dor Z, Paitan Y, Arielly H, Ahmad WA, Kelmer G, Fulde M, Steinman A. We aimed to investigate the prevalence, molecular characteristics and risk factors of extended-spectrum β-lactamase (ESBL)-producing (ESBL-E) shedding in horses. A prospective study included three cohorts: (i) farm horses (13 farms, n = 192); (ii) on hospital admission (n = 168) and; (iii) horses hospitalized for ≥72 h re-sampled from cohort (ii) (n = 86). Enriched rectal swabs were plated, ESBL-production was confirmed (Clinical and Laboratory Standards Institute (CLSI)) and genes were identified (polymerase chain reaction (PCR)). Identification and antibiotic susceptibility were determi...
ter Laak EA, Fennema G, Jaartsveld FH.Contagious Equine Metritis (CEM) was detected in the Netherlands for the first time in 1987. A total number of five mares (Dutch saddle-horse) were infected in three separate outbreaks. The origin of the infection could not be determined in any of the cases. As the isolates of the causal organism, Taylorella equigenitalis, showed auto-agglutination, diagnosis was difficult. Therefore, an indirect immune fluorescence test as used to diagnose the second isolate. Five strains were isolated, which all were resistant to streptomycin. The prevalence of CEM since 1981 is summarised. The importance of...
Ren J, Prescott JF.An 81 kb virulence plasmid containing a pathogenicity island (PI) plays a crucial role in the pathogenesis of Rhodococcus equi pneumonia in foals but its specific function in virulence and regulation of plasmid-encoded virulence genes is unclear. Using a LacZ selection marker developed for R. equi in this study, in combination with an apramycin resistance gene, an efficient two-stage homologous recombination targeted gene mutation procedure was used to mutate three virulence plasmid genes, a LysR regulatory gene homologue (ORF4), a ResD-like two-component response regulator homologue (ORF8), a...
Gilbertie JM, Schnabel LV, Stefanovski D, Kelly DJ, Jacob ME, Schaer TP.Bacterial colonization of synovial structures can cause infections that are difficult to treat. Systemic and local antimicrobials and repeated joint lavages are the mainstays of therapy. However, despite aggressive treatments, infection may persist, leading to significant tissue damage or death of the patient. In order to investigate the impact of bacterial culture and antimicrobial resistance on survival to discharge, we reviewed medical records of horses admitted to the University of Pennsylvania's large animal teaching hospital from 2010-2015. Two-hundred and six cases with a definitive dia...
Hu R, Yao R, Li L, Xu Y, Lei B, Tang G, Liang H, Lei Y, Li C, Li X, Liu K, Wang L, Zhang Y, Wang Y, Cui Y, Dai J, Ni W, Zhou P, Yu B, Hu S.With the rapid development of high-throughput sequencing technology, the amount of metagenomic data (including both 16S and whole-genome sequencing data) in public repositories is increasing exponentially. However, owing to the large and decentralized nature of the data, it is still difficult for users to mine, compare, and analyze the data. The animal metagenome database (AnimalMetagenome DB) integrates metagenomic sequencing data with host information, making it easier for users to find data of interest. The AnimalMetagenome DB is designed to contain all public metagenomic data from animals,...
Buczkowska J, Kozdrowski R, Nowak M, Raś A, Staroniewicz Z, Siemieniuch MJ.Endometritis is a major cause of infertility in the mare. Therefore, the diagnosis of this disease is very important in veterinary practice. The objective of this study was to compare bacteriological and cytological results obtained from the mare uterus using biopsy (EB) and cytobrush (CB) techniques and relating these findings to the presence of polymorphonuclear cells (PMNs) in endometrial tissue as the gold standard for detection of endometritis. In particular, we tested the hypothesis that endometrial cytology and microbiology data obtained from material collected using the EB and CB techn...
Jensen BB.Studies of methanogenic bacteria present in monogastric animals are still scarce. Methanogens have been isolated from faeces of rat, horse, pig, monkey, baboon, rhinoceros, hippopotamus, giant panda, goose, turkey and chicken. The predominant methanogen in all except the chicken and turkey is species of Methanobrevibacterium. The chicken and turkey harbour species of Methanogenium. In pig the population of methanogenic bacteria is more than 30 times as dense in the distal colon as in the caecum. This finding is in agreement with the finding that the rate of methane production is much higher in...
Mitchell CJ, O'Sullivan CM, Pinloche E, Wilkinson T, Morphew RM, McEwan NR.Next-generation sequencing of DNA from nematode eggs has been utilised to give the first account of the equine 'nemabiome'. In all equine faecal samples investigated, multiple species of Strongylidae were detected, ranging from 7.5 (SEM 0.79) with 99+% identity to sequences in the NCBI database to 13.3 (SEM 0.80) with 90+% identity. This range is typical of the number of species described previously in morphological studies using large quantities of digesta per animal. However, the current method is non-invasive; relies on DNA analysis, avoiding the need for specialist microscopy identificatio...
Klebanoff SJ, Agosti JM, Jörg A, Waltersdorph AM.Stimulated eosinophils release cytotoxic granule constituents, including eosinophil peroxidase (EPO) and a group of granule basic proteins (GBP). EPO reacts with H2O2 formed by the respiratory burst and a halide to form cytotoxic oxidants. The relative potency of the EPO-H2O2-halide system and the GBP is considered here. Horse eosinophils were induced to degranulate, the degranulation products were separated by chromatography on Sephadex G-50 and comparable volumes of the column fractions were tested for toxicity to Escherichia coli and the schistosomula of Schistosoma mansoni in the presence ...
Heidelberger M.Data accumulated over many years are brought together on cross-reactions of 46 among the more than 80 pneumococcal serological types, with the idea of correlating cross-reactions with the structures of the relevant type-specific capsular polysaccharides, insofar as these have been determined. The precipitin reaction was carried out with the polysaccharides and antibodies raised in horses, rabbits, and a mule. Quantitative values (micrograms of antibody nitrogen per milliliter of antiserum at 0 to 1 degree C) are given in many instances and discussed, together with arbitrary qualitative data, i...
Hashimoto-Hill S, Alenghat T.Domestic animals represent important resources for understanding shared mechanisms underlying complex natural diseases that arise due to both genetic and environmental factors. Intestinal inflammation, particularly inflammatory bowel disease (IBD), is a significant health challenge in humans and domestic animals. While the etiology of IBD is multifactorial, imbalance of symbiotic gut microbiota has been hypothesized to play a central role in disease pathophysiology. Advances in genomic sequencing and analytical pipelines have enabled researchers to decipher the composition of the intestinal mi...
Waters M, Raju D, Garmory HS, Popoff MR, Sarker MR.Recent epidemiological studies suggested that cpb2-positive Clostridium perfringens isolates are associated with gastrointestinal (GI) diseases in horses. These putative relationships, indicated by PCR genotyping, were tested in the present study by further genotyping and phenotyping of 23 cpb2-positive C. perfringens isolates from horses with GI disease (referred to hereafter as horse GI disease isolates). Our beta2-toxin (CPB2) Western blot analyses demonstrated that all of the tested isolates were unable to produce detectable levels of CPB2. However, Southern blot and nucleotide sequencing ...
Tyma JF, Epstein KL, Whitfield-Cargile CM, Cohen ND, Giguère S.OBJECTIVE To determine the effects of oral omeprazole administration on the fecal and gastric microbiota of healthy adult horses. ANIMALS 12 healthy adult research horses. PROCEDURES Horses were randomly assigned to receive omeprazole paste (4 mg/kg, PO, q 24 h) or a sham (control) treatment (tap water [20 mL, PO, q 24 h]) for 28 days. Fecal and gastric fluid samples were collected prior to the first treatment (day 0), and on days 7, 28, 35, and 56. Sample DNA was extracted, and bacterial 16S rRNA gene sequences were amplified and sequenced to characterize α and β diversity and differential ...
Pusterla N, Madigan JE, Chae JS, DeRock E, Johnson E, Pusterla JB.We report successful helminthic transmission of Ehrlichia risticii, the causative agent of Potomac horse fever, using trematode stages collected from Juga yrekaensis snails. The ehrlichial agent was isolated from the blood of experimentally infected horses by culture in murine monocytic cells and identified as E. risticii ultrastructurally and by characterization of three different genes.
