Gut health in horses refers to the condition and functioning of the equine gastrointestinal system, which includes the stomach, small intestine, cecum, and colon. This system is responsible for the digestion and absorption of nutrients, as well as the maintenance of a balanced microbiome. The gut microbiome, consisting of a diverse community of microorganisms, plays a role in digestion, metabolism, and immune function. Factors such as diet, stress, medication, and environmental changes can impact gut health, potentially leading to issues like colic or laminitis. This page compiles peer-reviewed research studies and scholarly articles that explore the anatomy, physiology, and microbial ecology of the equine gut, as well as the implications for overall horse health and management practices.
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...
Huang X, Li Q, Li X, Li C, Li J, He L, Jing H, Yang F, Li X.China's equine industry has shifted from traditional rough grazing to modern intensive farming, expanding the roles of horses into eventing, leisure, tourism, and meat and dairy production. Concurrently, equine nutrition has evolved from a forage-based diet to a more diverse regimen incorporating grain supplements to meet the heightened energy demands of intensive farming. However, nutrient digestibility and glycemic response vary considerably based on grain type, starch content, composition, and structural properties. Optimal grain selection is therefore essential for energy supplementation a...
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...
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...
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.
Zhu D, Li S, Xu Z, Kulyar MF, Bai X, Wang Y, Wang B, Khateeb E, Deng D, Wang L, Chen Y, Guo A, Shen Y.Diarrhea presents a substantial risk of high morbidity and mortality among foals. Although studies have shown connections between gut microbiota and several gastrointestinal diseases, there is still inadequate information on gut microbial alterations in foals during diarrhea. In this study, we conducted 16S rRNA and ITS gene amplicon sequencing to investigate gut bacterial and fungal differences between healthy and diarrheic foals. The results unveiled significant reductions in gut bacterial and fungal diversities among foals experiencing diarrhea, accompanied by notable shifts in the composit...
Lan Y, Li Y, Wang Y.In recent years, the importance of gut microbiota in digestive absorption, metabolism, and immunity has garnered increasing attention. China possess abundant horse breed resources, particularly Guizhou horses, which play vital roles in local agriculture, tourism, and transportation. Despite this, there is a lack of comparative studies on the gut microbiota of native Guizhou horses (GZH) and imported Dutch Warmblood horses (WH). To address this gap, fecal samples were collected from both GZH and WH, and 16S rRNA high-throughput sequencing was utilized to analyze the differences in their gut mic...
Fujimoto R, Kuchida M, Ban-Tokuda T, Matsui H.The equine large intestine harbors a diverse array of symbiotic microorganisms. Disruptions in the gut microbiota can lead to various diseases in horses. Probiotics offer promising avenues for enhancing equine health and performance. However, commercial formulations lack robust scientific validation. This study aimed to isolate and identify Lactobacillaceae and Bifidobacterium spp. from horse feces to explore their potential as probiotics. Fecal samples from Thoroughbred horses were subjected to isolation procedures. Lactic acid-producing bacteria were isolated using specific media and identif...
Hemeda AA, Zahran SA, Ali-Tammam M, Ewida MA, Kashef MT, Yassin AS, Mitra A, Youssef NH, Elshahed MS.The equine gut harbors a diverse microbial community and represents a rich source of carbohydrate-active enzymes (CAZymes). To identify and characterize potentially novel CAZymes from a horse's hindgut metagenome, shotgun metagenomic sequencing was performed on DNA extracted from a stool sample of a male horse, followed by CAZyme annotation. Here, we report on the characterization of a novel enzyme (AH2) that was identified, synthesized, cloned, and characterized from the obtained CAZyme dataset. AH2 was identified as a GH130 family member and displayed exclusive xylanase activity, a trait hit...
Penazzi L, Pagliara E, Nervo T, Ala U, Bertuglia A, Romano G, Hattab J, Tiscar PG, Bergagna S, Pagliasso G, Antoniazzi S, Cavallarin L, Valle E....Foals commonly experience diarrhoea in the first weeks of life. Although this condition is rarely life-threatening, it can have significant health consequences. This study investigated whether new-born foals can benefit from a dietary supplement of nucleotides, as already demonstrated in other species. Dietary nucleotides have positive effects on rapidly proliferating tissues and are considered "semi-essential nutrients" since cells have only a limited capacity to synthesize these compounds. The aim of this study was to investigate whether providing foals with a dietary nucleotide supplementat...
Arantes JA, Di Pietro R, Ratté M, Arroyo LG, Leclère M, Costa MC.Fecal microbiota transplantation (FMT) has been used as a treatment option for horses (Equus caballus) with gastrointestinal diseases. Several preparation and conservation protocols to improve bacterial survival have been studied in other species. Unassigned: This study aimed to evaluate the impact of oxygen exposure and different protectant solutions on bacterial viability before and after freezing using horse feces. Fecal samples from 10 healthy horses were aliquoted and diluted in cryoprotectant solutions containing antioxidants (n = 40) or 10% glycerol (n = 40). Half of the aliquots from e...
François AC, Cesarini C, Taminiau B, Renaud B, Kruse CJ, Boemer F, van Loon G, Palmers K, Daube G, Wouters CP, Lecoq L, Gustin P, Votion DM.Hypoglycin A and methylenecyclopropylglycine are protoxins responsible for atypical myopathy in equids. These protoxins are converted into toxins that inhibit fatty acid β-oxidation, leading to blood accumulation of acylcarnitines and toxin conjugates, such as methylenecyclopropylacetyl-carnitine. The enzymes involved in this activation are also present in some prokaryotic cells, raising questions about the potential role of intestinal microbiota in the development of intoxication. Differences have been noted between the faecal microbiota of cograzers and atypical myopathy-affected horses. Ho...
Wang W, Gibson J, Horsman S, Mikkelsen D, Bertin FR.Altered gut microbiota has been associated with dopaminergic degenerative diseases in people, but studies on horses with pituitary pars intermedia dysfunction (PPID) are lacking. Objective: Investigate the effect of PPID on fecal microbiota in horses. Methods: Nine horses with PPID and 13 age-matched control horses. Methods: Prospective control study. Fecal samples were collected bimonthly. Microbial analysis used 16S rRNA sequencing to determine the relative abundance at genus and phylum levels, assess alpha and beta diversity and identify core microbiota. Results: Horses with PPID had decrea...
Shi Y, Maga EA, Mienaltowski MJ.Diarrhea is a common disease that could threaten the welfare of newborn foals. While there are several forms of foal diarrhea, the etiologies can be considered known pathogenic or non-pathogenic in nature. Moreover, there are likely differences in the composition of microbial populations in the gastrointestinal tracts of foals depending upon the etiology of diarrhea. Our study aims to examine the microbial population in the feces of foals with both pathogenic and non-pathogenic diarrheas to discern differences in their microbial compositions. Results: Foal diarrhea samples tested positive or n...
Jarquín-Díaz VH, Dayaram A, Soilemetzidou ES, Desvars-Larrive A, Bohner J, Buuveibaatar B, Kaczensky P, Walzer C, Greenwood AD, Löber U.The microbial composition of host-associated microbiomes is influenced by co-evolutionary interactions, host genetics, domestication, and the environment. This study investigates the contribution of environmental microbiota from freshwater bodies to the gastrointestinal microbiomes of wild khulans (Equus hemionus hemionus, n = 21) and compares them with those of captive khulans (n = 12) and other equids-Przewalski's horse (n = 82) and domestic horse (n = 26). Using PacBio technology and the LotuS pipeline for 16S rRNA gene sequencing, we analyze microbial diversity and conduct ...
Żak-Bochenek A, Żebrowska-Różańska P, Bajzert J, Łaczmański Ł, Szponar B, Siwińska N, Gładysz K, Sikorska K, Chełmońska-Soyta A.Oral probiotic dietary supplements are widely used in veterinary medicine, including in horses. It is hypothesized that the presence of probiotic strains can both modulate the intestinal microbiota and affect mucosal immunity parameters. Such a study has not yet been conducted in horses. Unassigned: This study involved 12 healthy horses, which were randomly divided into a control group and a group that received a commercial oral probiotic formula containing , or for 84 days. Fecal samples were collected from all horses on day 0 (D0), 28 days after starting the probiotic (D28), 56 days (D56),...
Carter MM, Leatherwood JL, Paris BL, Moore GE, George JM, Martinez RE, Karges K, Cox JR, Arnold CE, Glass KG, Bradbery AN, Rodiles A, Wickersham TA.Thirty mature Quarter Horse geldings were used in a completely randomized 32-d study to test the hypotheses that supplemental live Saccharomyces cerevisiae CNCM I-1077 improves apparent digestion, stabilizes the fecal pH, reduces gut permeability, maintains microbial communities, and decreases inflammation in horses fed a high-starch diet. Horses were stratified by body weight, age, and body condition score (BCS) to one of two treatments: concentrate formulated with 2g starch • kg BW-1 • meal-1 (CON; n=15) or the same concentrate top-dressed with 25g/d Saccharomyces cerevisiae CNCM I-1077 ...
Nogacka AM, García A, de Los Reyes-Gavilán CG, Arboleya S, Gueimonde M.Horses are hindgut fermenters that harbor a complex intestinal microbiota (IM) which provides key enzymes aiding in the breakdown of complex carbohydrates present in their herbivorous diet. Therefore, these animals are deeply dependent on their IM for digestion and nutrition. Consequently, IM imbalances may result in alteration of fermentation patterns with impact on the animal health and the risk of disease. In this context, strategies for assisting the maintenance of a healthy IM in horses are of interest. However, there is limited research concerning the use of probiotics to improve hindgut...
Smith MZ, York M, Townsend KS, Martin LM, Gull T, Coghill LM, Ericsson AC, Johnson PJ.Whereas restoration of fecal consistency after treatment with clioquinol for chronic diarrhea and free fecal water syndrome has been attributed to its antiprotozoal properties, actions of clioquinol on the colonic bacterial microbiota have not been investigated. Objective: Characterize the dynamics of fecal microbial diversity before, during, and after PO administration of clioquinol to healthy horses. Methods: Experimental prospective cohort study using a single horse group. Methods: Eight healthy adult horses received PO clioquinol (10 g, daily) for 7 days. Feces were obtained daily for ...
Brandi LA, Nunes AT, Faleiros CA, Poleti MD, Oliveira ECM, Schmidt NT, Sousa RLM, Fukumasu H, Balieiro JCC, Brandi RA.Different energy sources are often used in horse diets to enhance health and performance. Understanding how diet impacts the cecal and fecal microbiota is crucial for meeting the nutritional needs of horses. High-throughput sequencing and qPCR were used to compare the fecal and cecal microbiota of five healthy horses receiving three different diets: hay diet (HAY), hay + starch and sugar (SS), and hay + fiber and oil ingredients (FO). Assessment of short-chain fatty acids, pH, and buffer capacity was also performed. The HAY diet was associated with the highest values of fecal pH; the FO and SS...
Bishop RC, Shanthappa N, Connolly SL, Wilkins PA, McCoy AM.To establish the reference interval (RI) of fecal calprotectin (fCP) and fCP:protein ratio in the feces of healthy horses and demonstrate preliminary clinical utility for the quantification of intestinal inflammation. Methods: Feces were collected from healthy horses (n = 103) and horses with colic (n = 15) or colitis (n = 13). Feces were suspended in buffer to create fecal supernatant. Fecal calprotectin concentration was determined by ELISA, fecal total protein concentration was determined by bicinchoninic acid assay, and the fCP:protein ratio was calculated. Reference intervals for fCP and ...
Ma Y, Liu Y, Li H, Yang K, Yao G.Angular limb deformities (ALDs) are a common skeletal development disorder in newborn foals. This condition affects the growth and development of foals and severely impacts their future athletic performance and economic value, causing significant financial losses to the horse industry. Placentitis, metritis, and severe metabolic diseases during mare pregnancy are significant causes of ALDs in newborn foals. It has been established that intestinal flora disorders can easily lead to inflammatory and metabolic diseases in the host. However, the incidence of ALDs in foals in Zhaosu County, Xinjian...
Thomson P, Garrido D, Santibáñez R, Lara F.The gut microbiome plays a critical role in maintaining horse health, influencing digestion, immunity, and overall well-being. However, in certain conditions like colic, there is evidence of significant alterations in the microbial community. To analyze the composition of the fecal microbiome and the enriched predicted metabolic functions of horses with colic compared to a control group, 14 horses with colic and 14 control horses were recruited. From a stool sample, DNA extraction was carried out for subsequent 16S rRNA metagenomic analysis. The composition of the microbiome was analyzed from ...
Tuniyazi M, Tang R, Hu X, Zhang N.Laminitis is a serious health condition that can cause severe pain and lameness in horses. Due to lack of understanding of laminitis, treatments often fail to achieve the desired results. In recent years, we have begun to recognize that laminitis may involve a complex interaction between local and systemic inflammation. Dysbiosis of the gut microbiota has been linked in the development of systemic inflammation, and our previous findings suggest that the development of laminitis is closely linked to the production of harmful metabolites of the gut microbiota. In addition, it was found that loca...
To provide some glimpses on the possibility of shaping the human gut microbiome (GM) through probiotic exchange with natural ecosystems, here we explored the impact of 15 days of daily interaction with horses on the GM of 10 urban-living Italian children. Specifically, the children were in close contact with the horses in an "educational farm", where they spent almost 10 h/day interacting with the animals. The children's GM was assessed before and after the horse interaction using metabarcoding sequencing and shotgun metagenomics, along with the horses' skin, oral and fecal microbiomes. Targ...
Martínez-Aranzales JR, Córdoba-Agudelo M, Pérez-Jaramillo JE.Crib-biting is a stereotyped oral behavior with poorly understood etiology and pathophysiology. The relationship between the gut microbiome and brain function has been described in behavioral disorders such as schizophrenia, depression and anxiety in humans. In horses, studies of behavioral problems and the microbiome are very limited. This study aimed to characterize the fecal microbiome and the predicted functional profile of horses with and without aerophagia. Fecal samples were collected from 12 Colombian Creole Horses of both sexes, divided into two groups: group 1, composed of six horses...
Bell J, Radial SL, Cuming RS, Trope G, Hughes KJ.Diarrhea in foals can be associated with disruption of the intestinal microbiota (dysbiosis). Effective management of intestinal dysbiosis in foals has not been demonstrated. Objective: Fecal microbiota transplantation (FMT) in foals with diarrhea influences the intestinal microbiota and improves clinical and clinicopathological outcomes. Methods: Twenty-five foals <6 months of age with diarrhea and systemic inflammatory response syndrome at 3 veterinary hospitals. Methods: A prospective randomized placebo-controlled cohort study. Foals in the FMT group (n = 19) or control group (n =...
Li Z, Luo Z, Hu D.Diarrhea serves as a vital health indicator for assessing wildlife populations post-reintroduction. Upon release into the wild, wild animals undergo adaptation to diverse habitats and dietary patterns. While such changes prompt adaptive responses in the fecal microbiota, they also render these animals susceptible to gastrointestinal diseases, particularly diarrhea. This study investigates variations in fecal microorganisms and hormone levels between diarrhea-afflicted and healthy Przewalski's horses. The results demonstrate a significant reduction in the alpha diversity of the fecal bacterial ...
Mickevičienė I, Mikalauskienė D, Miknienė Z.Colic, a primary cause of illness and death in horses, necessitates the development of improved prognostic tools. Unassigned: The aim of this study was to investigate the prognostic significance of physiological and biochemical parameters in horses suffering from colic. Unassigned: A comprehensive clinical evaluation of 117 horses included assessment of heart rate, mucous membranes, capillary refill time, rectal temperature, respiratory rate, gut motility, reflux, and limb pulse strength. Unassigned: Stomach reflux, absence of gut noises, and increased heart rate (mean increase of 12 bpm) stro...
Biddle AS, Tomb JF, Fan Z.Due to modern management practices and the availability of energy dense feeds, obesity is a serious and increasingly common health problem for horses. Equine obesity is linked to insulin resistance and exacerbation of inflammatory issues such as osteoarthritis and laminitis. While the gut microbiome is thought to play a part in metabolic status in horses, bacterial communities associated with obesity have yet to be described. Here we report differences in metabolic factors in the blood of obese, normal and lean horses correlated with differences in gut microbiome composition. We report that ob...
Edwards JE, Shetty SA, van den Berg P, Burden F, van Doorn DA, Pellikaan WF, Dijkstra J, Smidt H.Equine gut microbiology studies to date have primarily focused on horses and ponies, which represent only one of the eight extant equine species. This is despite asses and mules comprising almost half of the world's domesticated equines, and donkeys being superior to horses/ponies in their ability to degrade dietary fiber. Limited attention has also been given to commensal anaerobic fungi and archaea even though anaerobic fungi are potent fiber degrading organisms, the activity of which is enhanced by methanogenic archaea. Therefore, the objective of this study was to broaden the current knowl...
Schoster A, Mosing M, Jalali M, Staempfli HR, Weese JS.The intestinal microbiota is important for health and disease. Factors that disturb the equine intestinal microbiota need further investigation. Objective: To determine the effects of transport, fasting and anaesthesia on the faecal microbiota of healthy adult horses using next-generation sequencing. Methods: Experimental trial. Methods: Faecal samples were taken from 8 horses at baseline, after transport, 12 h of fasting and 24, 48 and 72 h after a 6 h anaesthesia. Next generation sequencing of the V4 region of the 16S rRNA gene was used to assess the microbial composition of faeces. Alpha...
Lin C, Stahl DA.A total of six 16S rRNA targeted oligonucleotide probes were used to quantify Fibrobacter abundance and diversity in the gastrointestinal contents of a pony. Approximately 12% of the total 16S rRNA extracted from cecal contents hybridized with a Fibrobacter genus-specific probe and a Fibrobacter succinogenes species-specific probe. However, no significant hybridization was observed with a probe for the species. Fibrobacter intestinalis or with three probes for F. succinogenes subspecies. This suggested the presence of a previously undescribed population of F. succinogenes-like organisms. Novel...
Milinovich GJ, Burrell PC, Pollitt CC, Klieve AV, Blackall LL, Ouwerkerk D, Woodland E, Trott DJ.Alimentary carbohydrate overload is a significant cause of laminitis in horses and is correlated with drastic shifts in the composition of hindgut microbiota. Equine hindgut streptococcal species (EHSS), predominantly Streptococcus lutetiensis, have been shown to be the most common microorganisms culturable from the equine caecum prior to the onset of laminitis. However, the inherent biases of culture-based methods are estimated to preclude up to 70% of the normal caecal microbiota. The objective of this study was to evaluate bacterial population shifts occurring in the equine caecum throughou...
Morvan B, Bonnemoy F, Fonty G, Gouet P.Total number of bacteria, cellulolytic bacteria, and H2-utilizing microbial populations (methanogenic archaea, acetogenic and sulfate-reducing bacteria) were enumerated in fresh rumen samples from sheep, cattle, buffaloes, deer, llamas, and caecal samples from horses. Methanogens and sulfate reducers were found in all samples, whereas acetogenes were not detected in some samples of each animal. Archaea methanogens were the largest H2-utilizing populations in all animals, and a correlation was observed between the numbers of methanogens and those of cellulolytic microorganisms. Higher counts of...
Proudman CJ, Hunter JO, Darby AC, Escalona EE, Batty C, Turner C.The intestinal bacterial community of the horse is a key determinant of intestinal and whole body health. Understanding the bacterial community structure and function is an important foundation for studies of intestinal health and disease. Objective: To describe the faecal bacterial community and volatile organic compounds (VOCs) of the faecal metabolome of healthy Thoroughbred racehorses and to characterise responses to dietary supplementation with amylase-rich malt extract. Methods: Intervention study. Methods: Faecal samples were collected noninvasively before and 6 weeks after supplementat...
Zhao Y, Li B, Bai D, Huang J, Shiraigo W, Yang L, Zhao Q, Ren X, Wu J, Bao W, Dugarjaviin M.The hindgut of horses is an anaerobic fermentative chamber for a complex and dynamic microbial population, which plays a critical role in health and energy requirements. Research on the gut microbiota of Mongolian horses has not been reported until now as far as we know. Mongolian horse is a major local breed in China. We performed high-throughput sequencing of the 16S rRNA genes V4 hypervariable regions from gut fecal material to characterize the gut microbiota of Mongolian horses and compare them to the microbiota in Thoroughbred horses. Fourteen Mongolian and 19 Thoroughbred horses were use...
Bulmer LS, Murray JA, Burns NM, Garber A, Wemelsfelder F, McEwan NR, Hastie PM.Gut microbiota have been associated with health, disease and behaviour in several species and are an important link in gut-brain axis communication. Diet plays a key role in affecting the composition of gut microbiota. In horses, high-starch diets alter the hindgut microbiota. High-starch diets are also associated with increased behavioural reactivity in horses. These changes in microbiota and behaviour may be associated. This study compares the faecal microbiota and behaviour of 10 naïve ponies. A cross-over design was used with experimental groups fed high-starch (HS) or high-fibre (HF) die...
Lindenberg F, Krych L, Kot W, Fielden J, Frøkiær H, van Galen G, Nielsen DS, Hansen AK.Shortly after birth the mammalian gut is colonized, by a transient microbiota, highly susceptible to environment and diet, that eventually stabilizes and becomes the resident gut microbiota. In a window of opportunity during the colonization, oral tolerance is established towards resident bacteria. In this study, the development of the equine gut microbiota was investigated in ten foals from parturition until post weaning. We found great differences in the core species of the gut microbiota composition between time-matched samples on Day 7 and 20 post-partum. Between day 20 and Day 50 post-par...
Medina B, Girard ID, Jacotot E, Julliand V.Eight horses were allotted into pairs consisting of one cecum- and right ventral colon-fistulated animal and one cecum-fistulated animal. They were fed daily at the same level of intake either a high-fiber (HF) or a high-starch (HS) diet without or with 10 g of a Saccharomyces cerevisiae preparation, in a 4 x 4 Latin square design. The HS diet provided a starch overload (i.e., 3.4 g starch x kg(-1) BW x meal(-1)) while maintaining a high amount of fiber intake (i.e., dietary NDF/starch ratio was 1.0). A 21-d period of adaptation to the treatments occurred before cecal and colonic contents were...
Milinovich GJ, Trott DJ, Burrell PC, van Eps AW, Thoefner MB, Blackall LL, Al Jassim RA, Morton JM, Pollitt CC.In the horse, carbohydrate overload is thought to play an integral role in the onset of laminitis by drastically altering the profile of bacterial populations in the hindgut. The objectives of this study were to develop and validate microbial ecology methods to monitor changes in bacterial populations throughout the course of experimentally induced laminitis and to identify the predominant oligofructose-utilizing organisms. Laminitis was induced in five horses by administration of oligofructose. Faecal specimens were collected at 8 h intervals from 72 h before to 72 h after the administration ...
Grimm P, Philippeau C, Julliand V.Faeces could be used for evaluating the balance of the equine hindgut microbial ecosystem, which would offer a practical method for assessing gut health and how this relates to disease. However, previous studies concluded that faeces microbial ecosystem was not representative of the proximal hindgut (caecum and ventral colon). This study aimed to evaluate if variations of the faecal microbial ecosystem were similar to those observed in the proximal hindgut. Six horses, fistulated in the caecum and right ventral (RV) colon, were subjected to a gradual change of diet, from a 100% hay (high fibre...
Husso A, Jalanka J, Alipour MJ, Huhti P, Kareskoski M, Pessa-Morikawa T, Iivanainen A, Niku M.The establishment of the intestinal microbiota is critical for the digestive and immune systems. We studied the early development of the rectal microbiota in horse, a hindgut fermenter, from birth until 7 days of age, by qPCR and 16S rRNA gene amplicon sequencing. To evaluate initial sources of the foal microbiota, we characterised dam fecal, vaginal and oral microbiotas. We utilised an amplicon sequence variant (ASV) pipeline to maximise resolution and reproducibility. Stringent ASV filtering based on prevalence and abundance in samples and controls purged contaminants while preserving intest...
Moreau MM, Eades SC, Reinemeyer CR, Fugaro MN, Onishi JC.In the equine carbohydrate overload model of acute laminitis, disease progression is associated with changes in bacteria found in the cecum. To date, research has focused on changes in specific Gram-positive bacteria in this portion of the intestinal tract. Metagenomic methods are now available making it possible to interrogate microbial communities using animal protocols that sufficiently power a study. In this study, the microbiota in cecal fluid collected from control, non-laminitic horses (n=8) and from horses with early-stage acute laminitis induced with either oligofructan (n=6) or corns...
Quercia S, Freccero F, Castagnetti C, Soverini M, Turroni S, Biagi E, Rampelli S, Lanci A, Mariella J, Chinellato E, Brigidi P, Candela M.Even if horses strictly depend on the gut microbiota for energy homeostasis, only a few molecular studies have focused on its characterisation and none on the perinatal gut microbial colonisation process. Objective: To explore the perinatal colonisation process of the foal gut microbial ecosystem and the temporal dynamics of the ecosystem assembly during the first days of life. Methods: Longitudinal study. Methods: Thirteen Standardbred mare-foal pairs were included in the study. For each pair, at delivery we collected the mare amniotic fluid, faeces and colostrum, and the foal meconium. Milk ...
Schoster A, Weese JS, Guardabassi L.The gastrointestinal microbiota is extremely important for human and animal health. Investigations into the composition of the microbiota and its therapeutic modification have received increasing interest in human and veterinary medicine. Probiotics are a way of modifying the microbiota and have been tested to prevent and treat diseases. Probiotics are proposed to exert their beneficial effects through various pathways. Production of antimicrobial compounds targeting intestinal pathogens, general immune stimulation, and colonization resistance are among these mechanisms. Despite widespread ava...
Schoster A, Staempfli HR, Guardabassi LG, Jalali M, Weese JS.Diarrhea in foals affects up to 60% of foals during the first six months of life. The effect of diarrhea on the fecal bacterial microbiota in foals has not been investigated. Little is known on the fecal bacterial microbial richness and diversity of foals at a young age. The objective was to compare the fecal bacterial microbiota of healthy foals to foals with diarrhea at two and four weeks of life. Methods: Fecal samples were collected from foals (n = 20) at 1-14 (T1) and 15-28 (T2) days of age and analyzed using high throughput sequencing. Differences in relative abundance of bacterial tax...
Mach N, Ruet A, Clark A, Bars-Cortina D, Ramayo-Caldas Y, Crisci E, Pennarun S, Dhorne-Pollet S, Foury A, Moisan MP, Lansade L.We simultaneously measured the fecal microbiota and multiple environmental and host-related variables in a cohort of 185 healthy horses reared in similar conditions during a period of eight months. The pattern of rare bacteria varied from host to host and was largely different between two time points. Among a suite of variables examined, equitation factors were highly associated with the gut microbiota variability, evoking a relationship between gut microbiota and high levels of physical and mental stressors. Behavioral indicators that pointed toward a compromised welfare state (e.g. stereotyp...
Blackmore TM, Dugdale A, Argo CM, Curtis G, Pinloche E, Harris PA, Worgan HJ, Girdwood SE, Dougal K, Newbold CJ, McEwan NR.The horse, as a hindgut fermenter, is reliant on its intestinal bacterial population for efficient diet utilisation. However, sudden disturbance of this population can result in severe colic or laminitis, both of which may require euthanasia. This study therefore aimed to determine the temporal stability of the bacterial population of faecal samples from six ponies maintained on a formulated high fibre diet. Bacterial 16S rRNA terminal restriction fragment length polymorphism (TRFLP) analyses of 10 faecal samples collected from 6 ponies at regular intervals over 72 hour trial periods identifie...
Harlow BE, Lawrence LM, Flythe MD.Antibiotics are important to equine medicine, but antibiotic-associated diarrhea (AAD) can lead to poor performance and even mortality. AAD is attributed to disruption of the hindgut microbiota, which permits proliferation of pathogenic microbes. The goal of this study was to evaluate the effects of common antibiotics on cellulolytic bacteria, lactobacilli, and AAD-associated pathogens in the feces of healthy horses. Fifteen horses were assigned to three treatment groups (blocked by age and sex): control (no antibiotics), trimethoprim-sulfadiazine (PO), or ceftiofur (IM). Fecal samples (n=8 pe...
Walshe N, Duggan V, Cabrera-Rubio R, Crispie F, Cotter P, Feehan O, Mulcahy G.The interactions between parasitic helminths and gut microbiota are considered to be an important, although as yet incompletely understood, factor in the regulation of immunity, inflammation and a range of diseases. Infection with intestinal helminths is ubiquitous in grazing horses, with cyathostomins (about 50 species of which are recorded) predominating. Consequences of infection include both chronic effects, and an acute inflammatory syndrome, acute larval cyathostominosis, which sometimes follows removal of adult helminths by administration of anthelmintic drugs. The presence of cyathosto...
Li C, Li X, Guo R, Ni W, Liu K, Liu Z, Dai J, Xu Y, Abduriyim S, Wu Z, Zeng Y, Lei B, Zhang Y, Wang Y, Zeng W, Zhang Q, Chen C, Qiao J, Liu C, Hu S.As a domesticated species vital to humans, horses are raised worldwide as a source of mechanical energy for sports, leisure, food production, and transportation. The gut microbiota plays an important role in the health, diseases, athletic performance, and behaviour of horses. Here, using approximately 2.2 Tb of metagenomic sequencing data from gut samples from 242 horses, including 110 samples from the caecum and 132 samples from the rectum (faeces), we assembled 4142 microbial metagenome-assembled genomes (MAG), 4015 (96.93%) of which appear to correspond to new species. From long-read data, ...
McKinney CA, Oliveira BCM, Bedenice D, Paradis MR, Mazan M, Sage S, Sanchez A, Widmer G.Fecal microbial transplantation (FMT), a treatment for certain gastrointestinal conditions associated with dysbiosis in people, is also empirically employed in horses with colitis. This study used microbiota high-throughput sequencing to compare the fecal microbial profile of healthy horses to that of geriatric microbial transplant recipients experiencing diarrhea and tested whether FMT restores microbiota diversity. To evaluate the effect of environment and donor characteristics on the intestinal microbiota, fecal samples were collected per rectum from 15 healthy young-adult (2-12 years) and ...
Glinsky MJ, Smith RM, Spires HR, Davis CL.Three experiments, each utilizing three ponies, were conducted using a mixed VFA solution of [1−14C] acetate, [1−14C] propionate and [2–33H] butyrate to determine VFA production rates in the cecum of the pony. Diet A used in experiment 1, contained a forage to grain ratio of 1:2, while diet B, used in experiments 2 and 3, contained a forage to grain ratio of 3:1. Experiment 1, in which a constant infusion technique was used, resulted in net VFA production rates (mmoles/min) of 3.667 to 3.977 (x̄=3.836) for acetate, .410 to 1.664 (x̄=1.213) for propionate and .342 to 1.124 (x̄=.629) fo...
Santos AS, Rodrigues MA, Bessa RJ, Ferreira LM, Martin-Rosset W.Having evolved as a grazing animal, a horse's digestive physiology is characterized by rapid gastric transit, a rapid but intense enzymatic digestion along the small intestine, and a long and intense microbial fermentation in the large intestine. The process of understanding and describing feed degradation mechanisms in the equine digestive system in general, and in the hindgut ecosystem in particular, is essential. Regardless of its importance for the nutritional status of the host, the significance of the cecum-colon ecosystem has not yet been fully understood, and few reports have focused d...
Mackie RI, Wilkins CA.Samples from the duodenum, jejunum, and ileum, as well as from the cecum and colon, were obtained from 11 mature grass-fed horses. Viable counts of total culturable and proteolytic bacteria were made on habitat-simulating media containing 40% clarified ruminal fluid. The mean pHs in the duodenum, jejunum, and ileum were 6.32, 7.10, and 7.47, respectively; the mean pH decreased to 6.7 in the hindgut. The acetate concentration increased along the length of the small intestine and was the only volatile fatty acid present in this gut segment. Molar proportions of acetate, propionate, and butyrate ...
Ang L, Vinderola G, Endo A, Kantanen J, Jingfeng C, Binetti A, Burns P, Qingmiao S, Suying D, Zujiang Y, Rios-Covian D, Mantziari A, Beasley S....Domesticated horses live under different conditions compared with their extinct wild ancestors. While housed, medicated and kept on a restricted source of feed, the microbiota of domesticated horses is hypothesized to be altered. We assessed the fecal microbiome of 57 domestic and feral horses from different locations on three continents, observing geographical differences. A higher abundance of eukaryota (p < 0.05) and viruses (p < 0.05) and lower of archaea (p < 0.05) were found in feral animals when compared with domestic ones. The abundance of genes coding for microbe-...
De La Torre U, Henderson JD, Furtado KL, Pedroja M, Elenamarie O, Mora A, Pechanec MY, Maga EA, Mienaltowski MJ.A healthy gastrointestinal (GI) tract with a properly established microbiota is necessary for a foal to develop into a healthy weanling. A foal's health can be critically impacted by aberrations in the microbiome such as with diarrhea which can cause great morbidity and mortality in foals. In this study, we hypothesized that gut establishment in the foal transitioning from a diet of milk to a diet of grain, forage, and pasture would be detectable through analyses of the fecal microbiotas. Fecal samples from 37 sets of foals and mares were collected at multiple time points ranging from birth to...
Milinovich GJ, Trott DJ, Burrell PC, Croser EL, Al Jassim RA, Morton JM, van Eps AW, Pollitt CC.Carbohydrate-induced laminitis in horses is characterized by marked changes in the composition of the hindgut microbiota, from a predominantly Gram-negative population to one dominated by Gram-positive bacteria. The objective of this study was to monitor changes in the relative abundance of selected hindgut bacteria that have previously been implicated in the pathophysiology of equine laminitis using fluorescence in situ hybridization (FISH). Caecal cannulae were surgically implanted in five Standardbred horses and laminitis induced by oral administration of a bolus dose of oligofructose. Caec...
