The equine microbiome refers to the diverse community of microorganisms, including bacteria, fungi, and viruses, residing in various parts of a horse's body, such as the gastrointestinal tract, skin, and respiratory system. These microorganisms are involved in numerous physiological processes, including digestion, metabolism, and immune function. The composition and diversity of the microbiome can be influenced by factors such as diet, environment, and health status. Research in this area explores the characterization of the equine microbiome, its impact on health and disease, and potential applications in managing equine health. This page compiles peer-reviewed research studies and scholarly articles that investigate the composition, function, and implications of the microbiome in horses.
Muhonen S, Sadet-Bourgeteau S, Julliand V.Fibrous feeds are essential for horses. When developing feeding regimens promoting health and performance, we need to understand the digestion of plant cell walls and the functioning of the hindgut microbial ecosystem. Our objective was to investigate the effect of grass fibre maturity and legume forage on the hindgut microbiota and its activity. Six caecum and colon fistulated geldings were fed three diets differing in fibre composition: concentrate and late harvested grass haylage (35:65 energy ratio) (C); early and late harvested grass haylage (80:20) (G); lucerne and late harvested grass h...
Paul LJ, Ericsson AC, Andrews FM, Keowen ML, Morales Yniguez F, Garza F, Banse HE.The role of the gastric microbiome in development or persistence of equine glandular gastric disease (EGGD) remains to be investigated. Objective: The objective was to characterize the glandular mucosal and gastric fluid microbiomes of horses with and without EGGD. It was hypothesized that differences in the mucosal microbiome are associated with EGGD. Methods: Twenty-four horses were enrolled. Methods: Gastroscopy was performed and EGGD scores recorded (score 0, n = 6; score 1, n = 8; score ≥2, n = 10). Gastric fluid and pinch biopsies of healthy glandular mucosa and EGGD lesions were...
Fernandes KA, Gee EK, Rogers CW, Kittelmann S, Biggs PJ, Bermingham EN, Bolwell CF, Thomas DG.Seasonal variation in the faecal microbiota of forage-fed horses was investigated over a 12-month period to determine whether the bacterial diversity fluctuated over time. Horses ( = 10) were maintained on pasture for one year, with hay supplemented from June to October. At monthly intervals, data were recorded on pasture availability and climate (collected continuously and averaged on monthly basis), pasture and hay samples were collected for nutrient analysis, and faecal samples were collected from all horses to investigate the diversity of faecal microbiota using next-generation sequencing ...
Juśkiewicz J, Fotschki B, Jaworska J, Siemieniuch M.Gastrointestinal microbiota play a key role in the nutrients digestion and hence maintaining animal health and welfare. The diet offered to the animals in captivity may differ considerably from that on natural pastures. In a stabled maintenance system, horses have a limited choice of habitat and feed. Time spend for feeding is relevant for equine welfare because the reduction of the time devoted for foraging may be responsible for inducing gastric inflammation and ulceration. Therefore, in the present study, it was hypothesized that fecal bacterial fermentative processes differ between free-ro...
Godwin T, Webb G, Lancaster P.Previous research indicates equine fecal inoculates produce comparable results to cecal fluid when used for in vitro procedures to analyze dry matter digestibility (DMD). Equine hindgut microbial communities represented in fecal samples have been shown to be affected by diet. The study's objective was to determine the effect of the donor diet on in vitro DMD when fecal donors were fed high starch, or high fiber diets. Six Quarter Horses were used in a crossover design to compare the effects of a grain versus forage diet on in vitro digestion of forages ranging from: CP 7.7 to 16.4 %DM, NDF 53 ...
Jiménez BLM, Elghandour MMMY, Adegbeye MJ, Tirado González DN, Tirado Estrada G, Salem AZM, Pacheco EBF, Pliego AB.In the race against deadly diseases, multiple drugs have been developed as a treatment strategy in livestock. Each treatment is based on a specific mechanism to find a suitable drug. Antibiotics have become a fundamental part of the equine industry to treat bacterial diseases. These antibiotics have specific doses and side effects, and understanding each parameter allows veterinarians to avoid or limit the adverse effects of such drugs. Use of antibiotics causes microbial imbalance, decreased microbial diversity and richness in both cecal and fecal samples. Antibiotics reduced metabolites prod...
Arnold CE, Pilla R, Chaffin MK, Leatherwood JL, Wickersham TA, Callaway TR, Lawhon SD, Lidbury JA, Steiner JM, Suchodolski JS.The fecal microbiome of healthy horses may be influenced by signalment, diet, environmental factors, and disease. Objective: To assess the effects of age, breed, sex, geographic location, season, diet, and colitis caused by antibiotic use (antimicrobial-associated diarrhea [AAD]) and Salmonella infection on fecal microbiota. Methods: Healthy horses (n = 80) were sampled from nonhospital environments across multiple geographical locations in the United States. Horses with AAD (n = 14) were defined as those that developed diarrhea secondary to antimicrobial use. Horses with Salmonella infect...
Johnson ACB, Biddle AS.Thriftiness in horses has been associated with more efficient nutrient harvesting in digestion, absorption and/or utilization, but the relative contribution of the gut microbiome to host metabolic tendency is not well understood. Recognizing the unreliability of owner reported assignment of keeper status, this research describes a novel tool for calculating whether a horse is an easy (EK) or hard (HK) keeper and then characterizes microbiome differences in these groups. The Equine Keeper Status Scale (EKSS) was developed and validated based on data gathered from 240 horses. Estimates of dietar...
O'Shaughnessy-Hunter LC, Yu A, Rousseau JD, Foster RA, Weese JS.Next-generation sequencing techniques have revealed that human and animal skin is colonised by a rich and diverse population of bacteria, and that microbial composition varies between different body sites and individuals. Very little is known about the normal microbiota of healthy equine skin. Objective: To describe the taxonomic distributions of cutaneous bacterial microbiota in a population of healthy horses in Ontario, Canada, and to evaluate the effects of body site, individual and time of year on microbial diversity and community composition. Methods: Samples were collected from four body...
Leng J, McNally S, Walton G, Swann J, Proudman C, Argo C, Emery S, La Ragione R, Eustace R.Gut microbial communities are increasingly being linked to diseases in animals and humans. Obesity and its associated diseases are a concern for horse owners and veterinarians, and there is a growing interest in the link among diet, the intestinal microbiota and metabolic disease. Objective: Assess the influence of long-term hay or haylage feeding on the microbiota and metabolomes of 20 Welsh mountain ponies. Methods: Longitudinal study. Methods: Urine, faeces and blood were collected from 20 ponies on a monthly basis over a 13-month period. Urine and faeces were analysed using proton magnetic...
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...
Walshe N, Cabrera-Rubio R, Collins R, Puggioni A, Gath V, Crispie F, Cotter PD, Brennan L, Mulcahy G, Duggan V.Obesity is endemic in human populations in the western society, and with mounting evidence that the intestinal ecological environment plays a major role in its pathogenesis, identification of therapies based on intestinal microbiota modulation are gaining attention. Obesity in companion animals is also a common clinical problem. We set out using a multidimensional approach, to determine the effectiveness and safety of a weight loss program for horses incorporating diet restriction and exercise. In addition, we aimed to investigate the effect of this program on the overall intestinal health of ...
Arnold C, Pilla R, Chaffin K, Lidbury J, Steiner J, Suchodolski J.Diarrhea is an adverse effect of antimicrobial therapy in horses. This matched, case-controlled study compared the fecal microbiome and metabolome of horses on antibiotics that developed diarrhea (AAD, = 17) to those that did not develop diarrhea (ABX, = 15) and to a control population not exposed to antibiotics (CON, = 31). Fecal samples were collected from horses that were matched for diet and antimicrobial agent (including dose, route, and duration of therapy). Illumina sequencing of 16S rRNA genes was performed, and QIIME 2.0 was used to generate alpha and beta diversity metrics. Untarg...
Park T, Cheong H, Yoon J, Kim A, Yun Y, Unno T.(1) Background: The intestinal microbiota plays an essential role in maintaining the host's health. Dysbiosis of the equine hindgut microbiota can alter the fermentation patterns and cause metabolic disorders. (2) Methods: This study compared the fecal microbiota composition of horses with intestinal disease and their healthy counterparts living in Korea using 16S rRNA sequencing from fecal samples. A total of 52 fecal samples were collected and divided into three groups: horses with large intestinal disease (n = 20), horses with small intestinal disease (n = 8), and healthy horses (n = 24). (...
Theelen MJP, Luiken REC, Wagenaar JA, Sloet van Oldruitenborgh-Oosterbaan MM, Rossen JWA, Zomer AL.Several studies have described the faecal microbiota of horses and the factors that influence its composition, but the variation in results is substantial. This study aimed to investigate the microbiota composition in healthy equids in The Netherlands under standard housing and management conditions and to evaluate the effect of age, gender, horse type, diet, pasture access, the season of sampling and location on it. Spontaneously produced faecal samples were collected from the stall floor of 79 healthy horses and ponies at two farms. The validity of this sampling technique was evaluated in a ...
Kinoshita Y, Niwa H, Uchida-Fujii E, Nukada T.Microbial communities are commonly studied by using amplicon sequencing of part of the 16S rRNA gene. Sequencing of the full-length 16S rRNA gene can provide higher taxonomic resolution and accuracy. To obtain even higher taxonomic resolution, with as few false-positives as possible, we assessed a method using long amplicon sequencing targeting the rRNA operon combined with a CCMetagen pipeline. Taxonomic assignment had > 90% accuracy at the species level in a mock sample and at the family level in equine fecal samples, generating similar taxonomic composition as shotgun sequencing. The...
Valdez-Miramontes CE, De Haro-Acosta J, Aréchiga-Flores CF, Verdiguel-Fernández L, Rivas-Santiago B.Antimicrobial peptides (AMPs) are molecules with a broad-spectrum activity against bacteria, fungi, protozoa, and viruses. These peptides are widely distributed in insects, amphibians and mammals. Indeed, they are key molecules of the innate immune system with remarkable antimicrobial and immunomodulatory activity. Besides, these peptides have also shown regulatory activity for gut microbiota and have been considered inductors of growth performance. The current review describes the updated findings of antimicrobial peptides in domestic animals, such as bovines, goats, sheep, pigs, horses, cani...
Lindenberg FC, Lützhøft DO, Krych L, Fielden J, Kot W, Frøkiær H, van Galen G, Nielsen DS, Hansen AK.Some oligosaccharides induce growth of anti-inflammatory bacterial species and induce regulatory immunity in humans as well as animals. We have shown that the equine gut microbiota and the immune-microbial homeostasis largely stabilize within the first 50 days of life. Furthermore, we have previously established that certain bacterial species in the equine gut correlated with regulatory immunity. Accordingly, we hypothesized that an oligosaccharide rich diet fed to foals during the first 50 days would increase the abundance of bacterial species associated with regulatory immunity, and that thi...
Park T, Yoon J, Kim A, Unno T, Yun Y.(1) Background: The large intestine of horses is an anaerobic fermentative chamber filled with fibrolytic bacteria that play essential roles in digesting and absorbing nutrients for energy production. Although Jeju horses are a prominent local breed in Korea, few studies have investigated the gut microbiota of Jeju horses; (2) Methods: This study performed sequencing of V3 and V4 hypervariable regions of the partial 16S rRNA genes obtained from horse fecal samples and compared the gut microbiota between Jeju and Thoroughbred horses. Thirty and 24 fecal samples were obtained from Jeju and Thoro...
Hu D, Chao Y, Zhang B, Wang C, Qi Y, Ente M, Zhang D, Li K, Mok KM.Horse botflies have been a threat to the Przewalski's horses in the Kalamaili Nature Reserve in Xinjiang of China since their reintroduction to the original range. As larvae of these parasites could infest the intestine of a horse for months, they could interact with and alter the structure and composition of its intestinal microbiota, affecting adversely its health. Nonetheless, there are no such studies on the rewilded Przewalski's horses yet. For the first time, this study characterizes the composition of the intestinal microbiota of 7 rewilded Przewalski's horses infected severely by Gaste...
Zhu Y, Wang X, Deng L, Chen S, Zhu C, Li J.Diet is an important factor affecting intestinal microbiota in horses. Fecal microbiota is commonly used as a substitute for studying hindgut microbiota when investigating the relationship between intestinal microbial changes and host health. So far, no study has compared the difference between the fecal microbiota found in horses that are fed pasture grass, silage, and hay. The present study aims to characterize the fecal microbiota in horses that were exclusively on one of the three forage diets, and to analyze the potential impact of these forages, especially silage, on horse intestinal hea...
Collinet A, Grimm P, Julliand S, Julliand V.In horses, abrupt changes from high-fiber (HF) to high-starch (HS) diets can affect the cecal and colonic microbiota. This study investigated modifications and recovery of fecal microbiota after two consecutive abrupt dietary changes. Twelve horses fed HF for 2 weeks were changed to HS for 5 days then returned to HF for 7 weeks. Six received lactic acid bacteria supplementation. Bacterial population diversity, structure, and activity, especially fibrolysis, were assessed to obtain an overview of alteration in hindgut microbiota. Two days after the abrupt change from HF to HS, the findings in f...
Mitchell S, Bull M, Muscatello G, Chapman B, Coleman NV.Antibiotic resistance in bacterial pathogens is a growing problem for both human and veterinary medicine. Mobile genetic elements (MGEs) such as plasmids, transposons, and integrons enable the spread of antibiotic resistance genes (ARGs) among bacteria, and the overuse of antibiotics drives this process by providing the selection pressure for resistance genes to establish and persist in bacterial populations. Because bacteria, MGEs, and resistance genes can readily spread between different ecological compartments (e.g. soil, plants, animals, humans, wastewater), a "One Health" approach is need...
Zhu Y, Chen S, Yi Z, Holyoak R, Wang T, Ding Z, Li J. subsp. equi () is the pathogen causing strangles, a highly infectious disease that can affect equids including donkeys of all ages. It can persistently colonize the upper respiratory tract of animals asymptomatically for years, which serves as a source of infection. Several strangles outbreaks have been reported in the donkey industry in China in the last few years and pose a great threat to health, production, and the welfare of donkeys. Nasopharyngeal swab samples for culture and PCR are used widely in strangles diagnosis. Additionally, microbiomes within and on the body are essential to ho...
Kushugulova A, Löber U, Akpanova S, Rysbekov K, Kozhakhmetov S, Khassenbekova Z, Essex M, Nurgozhina A, Nurgaziyev M, Babenko D, Markó L....Probiotics and prebiotics are widely used for recovery of the human gut microbiome after antibiotic treatment. High antibiotic usage is especially common in children with developing microbiome. We hypothesized that dry Mare's milk, which is rich in biologically active substances without containing live bacteria, could be used as a prebiotic in promoting microbial diversity following antibiotic treatment in children. The present pilot study aims to determine the impacts of dry Mare's milk on the diversity of gut bacterial communities when administered during antibiotic treatment and throughout ...
Boshuizen B, Moreno de Vega CV, De Maré L, de Meeûs C, de Oliveira JE, Hosotani G, Gansemans Y, Deforce D, Van Nieuwerburgh F, Delesalle C.Aleurone, a layer of the bran fraction, is deemed to be responsible for the positive health effects associated with the consumption of whole-grain products. Studies on rodents, pigs, and humans report beneficial effects of aleurone in five main areas: the reduction of oxidative stress, immunomodulatory effects, modulation of energy management, digestive health, and the storage of vitamins and minerals. Our study is the first aleurone supplementation study performed in horses. The aim of this study was to investigate the effect of an increase in the dose levels of aleurone on the postprandial g...
Kaiser-Thom S, Hilty M, Axiak S, Gerber V.Equine pastern dermatitis (EPD), a multifactorial syndrome, manifests as skin lesions of variable severity in the pastern area. Despite the widespread use of antibacterial therapy for treating this condition, little is known about the contributing bacteria. Objective: To investigate the bacterial skin microbiota in EPD-affected and unaffected (control) pasterns. Methods: Case-control study with 80 client-owned horses; each with at least one EPD-affected and one control pastern. Methods: Horses were grouped by the form of EPD (mild, exudative or proliferative), the assigned severity grade and t...
Mach N, Moroldo M, Rau A, Lecardonnel J, Le Moyec L, Robert C, Barrey E.Endurance exercise has a dramatic impact on the functionality of mitochondria and on the composition of the intestinal microbiome, but the mechanisms regulating the crosstalk between these two components are still largely unknown. Here, we sampled 20 elite horses before and after an endurance race and used blood transcriptome, blood metabolome and fecal microbiome to describe the gut-mitochondria crosstalk. A subset of mitochondria-related differentially expressed genes involved in pathways such as energy metabolism, oxidative stress and inflammation was discovered and then shown to be associa...
Hesta M, Costa M.Many horses are fed differently than their wild ancestors. They often have limited access to pasture and are fed conserved forage and concentrates rich in starch and sugars, in only 2 meals per day. Feeding practices in contrast to natural feeding behavior can lead to gastrointestinal issues. Standard nutritional evaluation is warranted because of its important role in prevention and in treatment and management of diseases. When medical and nutritional treatments are combined, success rates are higher. New techniques to characterize equine microbiota have been used, allowing for microbiota man...
Ericsson AC, Johnson PJ, Gieche LM, Zobrist C, Bucy K, Townsend KS, Martin LM, LaCarrubba AM.Common treatments for Equine Metabolic Syndrome (EMS) and associated conditions include removal from pasture and adoption of an all-hay diet. Pharmacological treatments for EMS include metformin, a biguanide antihyperglycemic agent also administered to people to help improve glucose tolerance and insulin sensitivity. Both treatments may work, at least partially, through the gut microbiota, yet little is known regarding these effects in the equine host. To determine the influence on the fecal microbiota of this diet change and administration of metformin, six healthy horses were removed from pa...
Virendra A, Gulavane SU, Ahmed ZA, Reddy R, Chaudhari RJ, Gaikwad SM, Shelar RR, Ingole SD, Thorat VD, Khanam A, Khan FA.The application of high throughput technologies has enabled unravelling of unique differences between healthy mares and mares with endometritis at transcriptomic and proteomic levels. However, differences in the uterine microbiome are yet to be investigated. Objective: The present study was aimed at evaluating the differences in uterine microbiome between healthy mares and mares with endometritis. Methods: Low-volume lavage (LVL) samples were collected from the uterus of 30 mares classified into healthy (n = 15) and endometritis (n = 15) based on their reproductive history, intrauterine fl...
Salem SE, Hough R, Probert C, Maddox TW, Antczak P, Ketley JM, Williams NJ, Stoneham SJ, Archer DC.Periparturient mares are at increased risk of colic including large colon volvulus, which has a high mortality rate. Alterations in colonic microbiota related to either physiological or management changes, or both, that occur at this time have been suggested as potential causes for increased colic risk in this population of horses. Although the effect of management changes on the horse faecal microbiota has been investigated, limited work has been conducted to investigate changes in faecal microbiota structure and function in the periparturient period. The objectives of the current study were ...
Hu D, Yang J, Qi Y, Li B, Li K, Mok KM.Intestinal microbiota is involved in immune response and metabolism of the host. The frequent use of anthelmintic compounds for parasite expulsion causes disturbance to the equine intestinal microbiota. However, most studies were on the effects of such treatment on the intestinal bacterial microbes; none is on the entire microbial community including archaea and eukaryotic and viral community in equine animals. This study is the first to explore the differences of the microbial community composition and structure in Przewalski's horses prior to and following anthelmintic treatment, and to dete...
Tavenner MK, McDonnell SM, Biddle AS.Early development of the gut microbiome is an essential part of neonate health in animals. It is unclear whether the acquisition of gut microbes is different between domesticated animals and their wild counterparts. In this study, fecal samples from ten domestic conventionally managed (DCM) Standardbred and ten semi-feral managed (SFM) Shetland-type pony foals and dams were compared using 16S rRNA sequencing to identify differences in the development of the foal hindgut microbiome related to time and management. Results: Gut microbiome diversity of dams was lower than foals overall and within ...
Tang L, Yan L, Jia H, Xiong Y, Ma X, Chu H, Sun Z, Wang L, Shalitanati M, Li K, Hu D, Zhang D.Host-associated microbiota can significantly impact host fitness. Therefore, naturally occurring variations in microbiota may influence the health and persistence of their hosts. This finding is particularly important in reintroduced animals, as they typically experience habitat changes during translocations. However, little is known about how microbiomes are altered in response to conservation translocation. Here, we accessed the gut microbiome of Przewalski's horse (Equus przewalskii) populations in China from three nature reserves (i.e. Xinjiang Kalamaili Nature Reserve, KNR; Dunhuang Xihu ...
Muhonen S, Sadet-Bourgeteau S, Julliand V.Fibrous feeds are essential for horses. When developing feeding regimens promoting health and performance, we need to understand the digestion of plant cell walls and the functioning of the hindgut microbial ecosystem. Our objective was to investigate the effect of grass fibre maturity and legume forage on the hindgut microbiota and its activity. Six caecum and colon fistulated geldings were fed three diets differing in fibre composition: concentrate and late harvested grass haylage (35:65 energy ratio) (C); early and late harvested grass haylage (80:20) (G); lucerne and late harvested grass h...
Masty J, Stradley RP.The equine Paneth cell response to a shift in the microbial balance of the intestinal tract was studied by inducing an acute episode of alimentary laminitis in 6 mature ponies. The normal bacterial population of the gut was modified by administration of a carbohydrate-rich ration. During acute laminitis a dramatic degranulation of the Paneth cells occurred in the intestinal glands throughout the duodenum, jejunum, and ileum. Bacteriocidal lysozyme, which was immunohistochemically identified as a component of the Paneth cell secretory granule, was evident in the glandular lumina and in degranul...
Hu D, Chao Y, Li Y, Peng X, Wang C, Wang Z, Zhang D, Li K.Many studies on human intestinal microbiota indicate that gender difference is one of the key factors influencing microbial community composition. To date, the degree of influence that gender has on equid intestinal microbiota has not been reported. Thus, microbiota was analyzed in feces of seven female Przewalski's horses (FRPHs) and seven male Przewalski's horses (MRPHs) in this study, determining which microbiota characteristics respond to gender biases. The microbial community composition and structure were explored by 16S rRNA sequencing, followed by diversity analysis and difference anal...
Whitfield-Cargile CM, Cohen ND, Suchodolski J, Chaffin MK, McQueen CM, Arnold CE, Dowd SE, Blodgett GP.In equids, susceptibility to disease caused by Rhodococcus equi occurs almost exclusively in foals. This distribution might be attributable to the age-dependent maturation of immunity following birth undergone by mammalian neonates that renders them especially susceptible to infectious diseases. Expansion and diversification of the neonatal microbiome contribute to development of immunity in the gut. Moreover, diminished diversity of the gastrointestinal microbiome has been associated with risk of infections and immune dysregulation. We thus hypothesized that varying composition or reduced div...
Lucassen A, Hankel J, Finkler-Schade C, Osbelt L, Strowig T, Visscher C, Schuberth HJ.Feed supplements such as fermentation products (SCFP) alter immune responses in horses. The purpose of this study was to analyze whether a prebiotic activity of the SCFP alters the gut microbiome in horses. Racehorses were fed either SCFP (Olimond BB, OLI, = 6) or placebo pellets (PLA, = 5) for 43 days. Fecal microbiota analysis was performed using 16S rRNA gene sequencing. The numbers and function of circulating immune cell subpopulations were analyzed by flow cytometry. SCFP supplementation resulted in non-consistent differences in fecal microbiota between the PLA and OLI during the feedi...
McGorum BC, Chen Z, Glendinning L, Gweon HS, Hunt L, Ivens A, Keen JA, Pirie RS, Taylor J, Wilkinson T, McLachlan G.Equine grass sickness (EGS) is a multiple systems neuropathy of grazing horses of unknown aetiology. An apparently identical disease occurs in cats, dogs, rabbits, hares, sheep, alpacas and llamas. Many of the risk factors for EGS are consistent with it being a pasture mycotoxicosis. To identify potential causal fungi, the gastrointestinal mycobiota of EGS horses were evaluated using targeted amplicon sequencing, and compared with those of two control groups. Samples were collected post mortem from up to 5 sites in the gastrointestinal tracts of EGS horses (EGS group; 150 samples from 54 horse...
Zhu Y, Jiang W, Holyoak R, Liu B, Li J.The objective of this study was to investigate the oral microbial composition of the donkey and whether basic dental treatment, such as dental floating, would make a difference to the oral microbial environment in donkeys with dental diseases using high-throughput bacterial 16S rRNA gene sequencing. Oral swab samples were collected from 14 donkeys with various dental abnormalities on day 0 (before treatment) and day 20 (twenty days after treatment). It is the first report focusing on the oral microbiome in donkeys with dental diseases and the impact of common dental procedures thereon. Identif...
Foekel C, Schubert R, Kaatz M, Schmidt I, Bauer A, Hipler UC, Vogelsang H, Rabe K, Jahreis G.In a double-blind, placebo-controlled crossover trial, 23 patients consumed 250 ml mare's milk or placebo for 16 weeks. The aim was to examine the effects of mare's milk on the characteristics of atopic dermatitis (AD), on faecal microbiota and on clinical and immunological parameters. The intensity of AD was examined using the Severity Scoring of Atopic Dermatitis (SCORAD) index. During the mare's milk period, the mean SCORAD value of patients (n=23; 17 females, 6 males) decreased from 30.1 to 25.3 after 12 weeks (P<0.05) and to 26.7 after 16 weeks (P<0.1). In a subgroup (n=7) the SCORA...
Fitzgerald DM, Spence RJ, Stewart ZK, Prentis PJ, Sillence MN, de Laat MA.The equine microbiome can change in response to dietary alteration and may play a role in insulin dysregulation. The aim of this study was to determine the effect of adding pasture to a hay diet on the faecal bacterial microbiome of both healthy and insulin-dysregulated ponies. Faecal samples were collected from 16 ponies before and after dietary change to enable bacterial 16S rRNA sequencing of the V3-V4 region. The dominant phyla in all samples were the Firmicutes and Bacteroidetes. The evenness of the bacterial populations decreased after grazing pasture, and when a pony was moderately insu...
Sadet-Bourgeteau S, Philippeau C, Julliand V.Feeding a diet with a small amount of hay and a high proportion of concentrate given in large meals entails a risk of colic to horses as this can impact the hindgut microbial ecosystem. To counteract this potential negative effect, one feeding strategy is to modify the distribution sequence of concentrate and hay. The purpose of the present study was to assess the impact of feeding the concentrate meal before or with the hay meal on fermentative parameters postprandial variations in caecum and right ventral colon contents and faeces. We focused on the comparison of pH value and volatile fatty ...
Endo A, Futagawa-Endo Y, Dicks LM.Lactobacillus equi, Lactobacillus hayakitensis, Lactobacillus johnsonii, and Weissella confusa/cibaria were the dominant species in 12 South African horses. The Bifidobacterium-group was detected in the feces of only one of the 12 horses. Sequencing of the nested-PCR amplicon identified the Bifidobacterium-group as Parascardovia denticolens. Cell numbers of L. equi, L. hayakitensis, and W. confusa/cibaria were consistent in all samples. P. denticolens, Bifidodobacterium pseudolongum, and a phylogenetic relative of Alloscardovia omnicolens were rarely detected. L. equigenerosi, a dominant speci...
Mitchell S, Bull M, Muscatello G, Chapman B, Coleman NV.Antibiotic resistance in bacterial pathogens is a growing problem for both human and veterinary medicine. Mobile genetic elements (MGEs) such as plasmids, transposons, and integrons enable the spread of antibiotic resistance genes (ARGs) among bacteria, and the overuse of antibiotics drives this process by providing the selection pressure for resistance genes to establish and persist in bacterial populations. Because bacteria, MGEs, and resistance genes can readily spread between different ecological compartments (e.g. soil, plants, animals, humans, wastewater), a "One Health" approach is need...
Kopper JJ, Alexander TL, Kogan CJ, Berreta AR, Burbick CR.Fecal microbiota transplant (FMT), a technique used to restore normal intestinal microbial communities, has been successful in treating humans with Clostridioides difficile colitis. Subsequently, FMT is being used in veterinary patients with suspected intestinal dysbiosis. Unfortunately, little data are available regarding best practices for FMT in horses. The objective of this study was to evaluate the effects of storing manure prepared for equine FMT (MP-FMT) at -20°C for up to 4 weeks and passage through a simulated proximal gastrointestinal (GI) tract on the viability of MP-FMT. The resu...
Quiñones-Pérez C, Martínez A, Ortiz I, Crespo F, Vega-Pla JL.Despite the advances in reproductive technology, there is still a considerable number of low sperm quality cases in stallions. Recent studies in humans have detected several seminal microflora-spermatozoa associations behind some idiopathic infertility cases. However, no studies are available on horses, and there is limited information on the microflora present in stallion ejaculates. Accordingly, the objective of this study was to examine associations to the presence of bacteria families with five sperm quality parameters: concentration, total number of spermatozoa, total and progressive moti...
Zhang Z, Gao X, Dong W, Huang B, Wang Y, Zhu M, Wang C.Equines and ruminants have evolved as grazing herbivores with specialized gastrointestinal tracts capable of utilizing a wide range of fibrous feeds. In China, agricultural by-products, including corn straw, wheat straw, peanut vine, wheat husk, rice husk, and grass hay, have been extensively included in both equine and ruminant diets. These plant materials, which are composed predominantly of cellulose, hemicellulose, noncellulosic polysaccharides, and lignin, are largely undegradable by equines and ruminants themselves. Their breakdown is accomplished by communities of resident microorganism...
Gomez DE, Arroyo LG, Lillie B, Weese JS.The objective of this study was to investigate the nasal bacterial microbiota of healthy horses and horses infected with equine herpesvirus 1 (EHV-1). The nasal bacterial microbiota of 10 horses infected with EHV-1 and 11 control horses from a farm experiencing an outbreak was characterized using the Illumina MiSeq platform targeting the V4 region of the 16S ribosomal RNA gene. The nasal bacterial microbiota of healthy horses and EHV-1 horses was significantly different in community membership and structure. Horses shedding EHV-1 had lower bacterial richness ( = 0.002), evenness ( = 0.008), an...
Willette JA, Pitta D, Indugu N, Vecchiarelli B, Hennessy ML, Dobbie T, Southwood LL.An association between equine gastrointestinal disease causing colic signs and changes in faecal bacterial microbiota has been identified. The reasons for these changes and their clinical relevance has not been investigated. Withholding feed, which is an integral part of managing horses with colic, may contribute to the observed changes in the microbiota and impact interpretation of findings in horses with colic. Study objectives were, therefore, to determine the effect of withholding feed for 24 h on equine faecal bacterial microbiota in healthy mares to differentiate the effects of withhol...
Bino E, Lauková A, Ščerbová J, Kubašová I, Kandričáková A, Strompfová V, Miltko R, Belzecki G.The intestinal microbiota has enormous impact on the health and performance of horses. Staphylococci belong in the phylum Firmicutes, and their occurrence, especially of methicillin-resistant strains and species, has been reported in horses previously. Moreover, biofilm formation is one of the virulence factors; it has been not completely studied in fecal coagulase-negative staphylococci (CoNS) from horses. Therefore, this study was focused on biofilm formation by various species of fecal CoNS from horses because it has been never reported before. In addition, their antibiotic profile was test...
Park J, Kim EB.The ecosystem of an animal farm is composed of various elements, such as animals, farmers, plants, feed, soil, and microorganisms. A domesticated animal's health is largely connected with the reservoir of bacteria and viruses in animal farms. Although a few studies have focused on exploring the gut microbiome of animals, communities of microbiota and viruses in feedlots have not been thoroughly investigated. Methods: Here, we collected feces and dust samples (4 groups: cattle feces, C_F; horse feces, H_F; cattle dust, C_D; and horse dust, H_D) from cattle and horse farms sharing the same housi...
Kulikov EE, Golomidova AK, Efimov AD, Belalov IS, Letarova MA, Zdorovenko EL, Knirel YA, Dmitrenok AS, Letarov AV.Tailed bacteriophages constitute the bulk of the intestinal viromes of vertebrate animals. However, the relationships between lytic and lysogenic lifestyles of phages in these ecosystems are not always clear and may vary between the species or even between the individuals. The human intestinal (fecal) viromes are dominated mostly by temperate phages, while in horse feces virulent phages are more prevalent. To our knowledge, all the previously reported isolates of horse fecal coliphages are virulent. Temperate coliphage Hf4s was isolated from horse feces, from the indigenous equine Escherichia ...
Crotch-Harvey L, Thomas LA, Worgan HJ, Douglas JL, Gilby DE, McEwan NR.Anthelmintics are used as anti-worming agents. Although known to affect their target organisms, nothing has been published regarding their effect on other digestive tract organisms or on metabolites produced by them. The current work investigated effects of fenbendazole, a benzimidazole anthelmintic, on bacteria and ciliates in the equine digestive tract and on and their major metabolites. Animals receiving anthelmintic treatment had high faecal egg counts relative to controls. Analysis was performed over two weeks, with temporal differences detected in bacterial populations but with no other ...
Borkent D, Reardon RJM, McLACHLAN G, Glendinning L, Dixon PM.Although, peripheral caries (PC) affects almost half of UK horses, no comprehensive microbiological study has been performed on this disorder. As a high proportion of oral bacteria cannot be conventionally cultured, molecular microbiological techniques such as Next Generation Sequencing are required to examine the complex oral bacteria community. Objective: To identify the microbiota involved in equine PC, including comparing microbiota at the more commonly and severely affected three caudal cheek teeth with the less commonly affected three rostral cheek teeth. Methods: Equine dental plaque sa...
Park T, Yoon J, Kim A, Unno T, Yun Y.(1) Background: The large intestine of horses is an anaerobic fermentative chamber filled with fibrolytic bacteria that play essential roles in digesting and absorbing nutrients for energy production. Although Jeju horses are a prominent local breed in Korea, few studies have investigated the gut microbiota of Jeju horses; (2) Methods: This study performed sequencing of V3 and V4 hypervariable regions of the partial 16S rRNA genes obtained from horse fecal samples and compared the gut microbiota between Jeju and Thoroughbred horses. Thirty and 24 fecal samples were obtained from Jeju and Thoro...
Bond S, McMullen C, Timsit E, Léguillette R.The lower respiratory tract microbiota of the horse is different in states of health and disease, but the bacterial and fungal composition of the healthy respiratory tract of the horse has not been studied in detail. Objective: The respiratory tract environment contains distinct niche microbiotas, which decrease in species richness at more distal sampling locations. Objective: Characterize the bacterial and fungal microbiotas along the upper and lower respiratory tract of the horse. Methods: Healthy Argentinian Thoroughbred horses (n = 11) from the same client-owned herd. Methods: Prospectiv...
