Gastrointestinal health in horses encompasses the study of the structure, function, and disorders of the equine digestive system. The equine gastrointestinal tract is complex, consisting of the stomach, small intestine, cecum, and large intestine, each playing a specific role in digestion and nutrient absorption. Research in this area often focuses on common disorders such as colic, gastric ulcers, and parasitic infections, which can impact a horse's overall health and performance. Investigations examine factors affecting gastrointestinal health, including diet, management practices, and the microbiome. This page compiles peer-reviewed research studies and scholarly articles that explore the physiology, pathology, and management of gastrointestinal health in horses.
ALEXANDER F.No abstract available1. The magnitude of the rhythmic contractions of the perfused ileum varied with the supply of oxygen.
2. Isotonic sodium chloride solution was as good as Tyrode's solution for suspension of the red cells in the perfusion fluid.
3. Variation of the potassium and calcium content of the perfusion fluid had little effect on motility. Sodium ions had a specific function in maintaining motility.
4. The chloride ions in the perfusion fluid were replaced by bromide, phosphate and sulphate ions without affecting motility. Iodide ions were toxic.
5. The ileum perfused wi...
Bachmann M, Schusser GF, Wensch-Dorendorf M, Pisch C, Bochnia M, Santo MM, Netzker H, Woitow G, Thielebein J, Kesting S, Riehl G, Greef JM....Concentrations of starch, mono- and disaccharides, fructans, hemicellulose and cellulose were analysed in feed and gastric digesta of horses in relation to acid insoluble ash as a marker indigestible in the stomach. Twenty-four horses were allocated to pasture 24 h/d (PST; n = 4), hay ad libitum (HAY; n = 8), hay ad lib. and oats at 1 g starch/kg body weight (BWT)/meal (OS1; n = 6) and hay ad lib. and oats at 2 g starch/kg BWT/meal (OS2; n = 5). One horse was excluded from the analysis. The horses were fed the ration a minimum of 34 days. Following euthanasia and dissection, digesta was sample...
Hackett ES, McOnie RC, Buote NJ, Fubini SL.Equine minimally invasive surgical techniques are frequently utilized in the treatment of a variety of conditions. Standing sedated endoscopic surgery is commonly selected in horses, requiring specialized facilities, anesthetic protocols, and surgeon and assistant expertise. This review examines current methods and potential strategies in equine soft tissue surgery, in which there is an emphasis on laparoscopic urogenital and gastrointestinal diagnostic and therapeutic procedures. Thoracoscopy is less frequently reported in horses and may be underutilized. Optimizing procedures and outcomes in...
Forman R, Lalzar M, Inbar M, Berman TS.Reintroduced animals face disease risks, potentially impacting both the reintroduced and the local wildlife/domestic populations. This study focuses on the Asiatic wild asses () reintroduced to the Negev desert in southern Israel. Despite potential threats of disease spill-over to and from domesticated donkeys and horses in the area, there are no records of the gastrointestinal nematodes (GIN) of the wild ass population. We used DNA metabarcoding on fecal samples of wild asses collected across seasons and habitats, near water sources that they frequently use. Ten GIN species were detected in t...
Sousa LN, Winter IC, Varela DD, Luvison EZ, Guzmán JFC, Machado AMV, Figueiredo RDV, Pena GT, Dos Santos ACS, Faleiros RR, Carvalho AM.The present study involved seven horses in a randomized crossover clinical trial to evaluate the effect of lidocaine on horses with induced endotoxemia. Horses received intravenous lidocaine (1.5 mg/kg bolus, followed by 0.05 mg/kg bwt/min) or placebo (0.9% sodium chloride at the same manner) one hour before LPS administration (0.03 μg/kg, IV infusion over 30 min). We monitored clinic and hematologic parameters, abdominal auscultation, ultrasound, and pain over time. No relevant clinical differences existed between treatments regarding peristalsis, abdominal pain, or any other parameters befo...
Lensing R, Wirth C, Thünker F, Merle R, Barton AK.Gastric pH is a key factor in the development of equine squamous gastric disease (ESGD). Although acid injury is unlikely the primary cause of equine glandular gastric disease (EGGD), low pH may promote mucosal damage. Gastric pH is influenced by roughage uptake, as chewing increases the alkaline saliva production. The proton pump inhibitor omeprazole is currently recommended by the American/European College of Veterinary/Equine Internal Medicine (ACVIM/ECEIM) for ESGD and EGGD. We hypothesized that dental disorders decrease saliva production and gastric pH, predisposing horses to EGUS. Gastro...
Munsterman AS, Rogers-Tirado JM, Kottwitz J.To evaluate the effect of hand walking exercise on myoelectrical activity and contractility in normal, healthy horses. Methods: Prospective experimental design. A convenience sample of 8 horses were randomized to a control or hand walking treatment group; each horse underwent both treatments. After a 30-minute baseline electrointestinography (EIG), horses were stall rested or hand walked for 15 minutes. Electrointestinography was repeated immediately and at 2 hours. Ultrasonography and auscultation monitored cecal and left ventral colon (LVC) contractions during EIG. Electrointestinography spe...
Bishop RC, Kemper AM, Clark LV, Wilkins PA, McCoy AM.Equine gastrointestinal microbial communities vary across the gastrointestinal tract and in response to diet or disease. Understanding the composition and stability of gastric fluid microbiota in healthy horses is a prerequisite to understanding changes associated with the development of disease. The objective of this study was to describe microbial communities in the gastric fluid and feces of healthy horses longitudinally. Horses were maintained on pasture (6 weeks), stabled (5 weeks), then returned to pasture. A consistent forage diet was provided throughout. Native gastric fluid and feces ...
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 ...
Hodgson E, Thirouin M, Narayanan P, Romano TR, Wise J, Bond S.Current methods to measure intragastric pH in horses have limitations. A wireless capsule has been designed for continuous esophageal pH monitoring in humans. Objective: To (1) determine the feasibility and describe the methodology of measuring intragastric pH wirelessly in horses; and (2) determine attachment duration of the capsules. Methods: Eleven healthy adult horses. Methods: Capsules were attached to squamous and glandular gastric mucosa under gastroscopic guidance, using suture loops and 1 to 4 hemostasis clips. pH was continuously recorded using a wireless recorder in both fed and fas...
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...
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...
Guzmán JFC, Gontijo AS, Melgaço ES, Faria SA, Baldi MLC, Sousa LN, Wenceslau RR, Fantini P, Xavier ABDS, Beier SL.Morphine has significant clinical and analgesic effects in horses, but its impact on the gastrointestinal tract requires further understanding. This study assessed the analgesic and gastrointestinal effects of morphine in horses undergoing elective orchiectomy in the quadrupedal position. Thirty uncastrated male horses were randomly assigned to three groups: orchiectomy without morphine and sedation protocol (OSM), orchiectomy with morphine and sedation protocol (OM), and administration of morphine alone in the absence of orchiectomy (M). The anesthetic protocol involved acepromazine (0.05 mg/...
Żak-Bochenek A, Drábková Z, Sergedaite V, Siwińska N, Bajzert J, Pasak D, Chełmońska-Soyta A.Colic-related obstructions can reduced intestinal mucosa function and cause dysbiosis in horses, but it is unclear how defense barrier and secretory immunoglobulin A (SIgA) secretion is disrupted. Objective: The aim of the study is to evaluate the effect of severity of colic signs and treatments on fecal SIgA and fecal lactate in horses. Methods: Sixty-two client owned hospitalised horses with colic and eight healthy horses. Methods: Prospective clinical trial. Fecal samples were taken daily for 7 days. SIgA was analyzed using ELISA, and D/L-lactate measured with a commercial kit. Results: A...
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.
Munsterman AS, Dias Moreira AS, Kottwitz J.To evaluate the effects of detomidine on equine intestinal slow-wave activity and frequency distribution measured by electrointestinography (EIG). Methods: Prospective, experimental study. Methods: University teaching hospital. Methods: A convenience sample of twelve 7- to 21-year-old clinically normal horses. Methods: Horses were randomly assigned to saline control (four horses) or detomidine treatment (eight). After obtaining a 30-min baseline EIG, a saline or detomidine bolus was administered, followed by a constant rate infusion, and another EIG was recorded. Ultrasonographic examinations ...
Agrícola R, Ribeiro G, Borges J, Carvalho L, Roquet I, Carvalho LM, Prazeres J.Duodenal pathologies are underreported in equine medicine, probably not due to little occurrence, but due to the limitations of current diagnostic techniques. The aim of this report is to describe a novel duodenoscopic approach, that allows a complete visualization of a region inaccessible via standard techniques. Gastroduodenoscopy was performed in a clinical setting in 60 adult horses referred to us due to complaints suspected to be related to gastroduodenal diseases. The initial steps of the procedure were performed using previously published techniques. Once the video-endoscope reached the...
Morales CJ, Sykes BW, McKemie DS, Kass PH, Knych HK.Current treatment options for equine gastric ulcer syndrome (EGUS), such as omeprazole-a proton pump inhibitor (PPI)-have notable limitations, including the need for administration on an empty stomach. Potassium-competitive acid blockers (P-CABs), such as vonoprazan, are a newer class of acid suppressants that offer several advantages over PPIs in humans and may provide similar benefits in horses. Objective: To describe the pharmacokinetics and effect of a single oral dose of vonoprazan on intragastric pH in horses. We hypothesised that vonoprazan would follow linear kinetics across the doses ...
Busechian S, Di Salvo A, Orvieto S, Rueca F, Villella C, Sollevanti G, Pieramati C, Nisi I, Della Rocca G.Equine Gastric Ulcer Syndrome (EGUS) is a worldwide disease described in different categories of animals. A causal relationship between exercise and EGUS has been suggested, attributed to stress as well as physiological changes in the position of abdominal organs, especially during trot and gallop. EGUS can influence athletic fitness, as has been described in various papers on racehorses. The aim of this work was to determine if gastric ulcer healing is associated with changes in selected fitness parameters (i.e., speed, heart rate during exercise and recovery, stride length and frequency) in ...
Ventura Lopes Carvalho B, Neves de Souza MC, Souza Moreira N, Parisi Marliere J, Mesquita Mota JV, Drumond Bento L, de Castro Benitez A, Avanza MFB....Two routes of administration for electrolyte solutions are commonly used in horses with fluid, electrolyte, and acid-base imbalances: intravenous and nasogastric. Despite the frequent use of these routes, there are situations in which they cannot be applied. In such cases, intracecal fluid therapy represents a viable alternative, as this route enables the administration of enteral electrolyte solutions even in animals lacking normal anterior gastrointestinal function. This study aimed to evaluate the effects of a neutral hypotonic enteral electrolyte solution administered intracecally at two d...
Starrett A, Arnold CE, Burr A, Sarturi JO, Leatherwood JL, Pilla R, Awosile BB, Chaffin MK.To quantify gastrointestinal motility at 3 anatomic locations of the large colon in healthy horses fed 2 diets. Unassigned: 12 American Quarter Horses were enrolled in a prospective crossover study. Horses received either a complete pelleted diet fed at 1.35% body weight (BW) per day or Coastal Bermudagrass hay fed at 2% BW with 0.5% to 0.7% BW of complete pelleted feed. Each diet was fed for 13 days prior to motility assessment. Two ultrasonographers recorded the frequency of contractions at the sternal flexure of the large colon, left ventral colon, and cecum for 4 consecutive, 1-minute peri...
Castillo JDCR, Forte L, Elghandour MMMY, Maggiolino A, De Palo P, Ponce-Covarrubias JL, Salem AZM.Parasitic infections remain a major constraint to equine health and performance, and the worldwide rise of anthelmintic resistance is forcing a shift toward integrated parasite management and new complementary tools. Caesalpinia coriaria (Divi-divi) pods are exceptionally rich in tannins and have been proposed as a potential source of antiparasitic phytochemicals. This review summarizes the current evidence on C. coriaria, focusing on its relevance to equine gastrointestinal helminths. Most available data come from in vitro screening against ruminant nematode models (mainly Haemonchus contortu...
Cabaret J, Guerrero Molina C, Martínez-Ortiz-de Montellano C, Alcala Canto Y.Faecal egg counts (FECs) are used to assess the intensity of gastrointestinal nematode (GIN) infections in herbivores. FEC distribution is aggregated, meaning that approximately 20% of animals harbour 80% of infections. In times of escalating anthelmintic resistance, it may be necessary to restrict treatment to the animals with the heaviest infections. This strategy is called targeted selective treatment (TST) and is relevant to GIN, for example. The difficulty lies in identifying which animals to treat. One solution is to select potentially at-risk animals based on age (for example, treating ...
Watson W, MacKay JRD, Dwyer C.This study aims to improve the welfare and management of recreational horses by identifying how different management styles affect horse health and behaviour. We examined the management styles of recreational horse owners in the UK and Ireland, focusing on social interaction (friends), access to suitable forage (forage), and unrestricted movement (freedom). We collected 1,501 survey responses, distributed via social media, and summarised the characteristics and management choices of the respondents. Using the Divisive ANAlysis cluster package in R, three distinct management styles were identif...
Albrecht M, MacGillivray KC, Juez B, Freeland R.A 4.5-month-old Standardbred colt presented for neck swelling and fever. Endoscopy and contrast radiography identified a full thickness esophageal perforation. Surgical intervention with fasciotomies and placement of an esophageal feeding tube was elected. Intensive postoperative treatment was carried out with broad-spectrum antibiotics, gastroprotectants and probiotics, calculated feeding plan, esophagostomy and fasciotomy site lavages, care, and cleaning. Complications included recurrent bilateral pneumothorax and development of an incomplete fistula at the esophagostomy site following remov...
Neira-Egea P, Alamar Malvoisin C, de la Cuesta-Torrado M, Bautista-Erler C, Vitale V, Jolly S, Cesarini C. spp. are ubiquitous yeasts that are part of most mammals' microbiota and can become opportunistic pathogens under predisposing conditions. Interestingly, recent studies in human medicine report an increased abundance of spp. in association with inflammatory bowel disease (IBD). Gastrointestinal candidiasis has been primarily reported in neonatal foals, but not in adult horses. The aim of this study is to describe the morphological, histopathological, and microbiological features of gastric lesions associated with infiltration in five horses referred to two tertiary hospitals for different r...
Raidal SL, Freccero F, Carstens A, Weaver S, Padalino B.Transportation of horses has been associated with colic and changes to the gastrointestinal microbiome. Percutaneous abdominal ultrasonography using wireless, point-of-care transducers can be used to assess gastrointestinal motility in field settings. Unassigned: Characterization of intestinal motility and salivary cortisol responses of horses completing commercial transportation of 10-12h. Unassigned: Prospective observational study of 30 horses with diverse signalment and transport histories. Clinical parameters, sonographic assessment of intestinal motility and saliva samples, were collecte...
Kuzmina TA, Königová A, Burcáková L, Syrota Y, Babják M, Várady M.Strongylids and parascarids are the most widespread equine parasites worldwide; however, up-to-date data from Slovakia remain limited. This work bridges that gap by examining the prevalence and level of gastrointestinal helminth infections in Slovak horses. In the study, 392 fecal samples from horses on 24 farms were analyzed using the McMaster method with a sensitivity of 50 eggs per gram (EPG) for detecting nematode eggs and a double-centrifugation/combined sedimentation-flotation protocol for detecting Anoplocephala spp. eggs. Information on the age and breed of horses, management condition...
Freeman DE, Smith B, Bauck AG, Denagamage T, Moyer EK, Chanutin S.To develop a modified stapled (MS) jejunocecostomy (JC) in healthy horses. Methods: In vivo experimental study. Methods: Six healthy adult horses underwent ventral midline celiotomy, a jejunal resection, and an MS. Methods: Time to complete anastomosis and anastomotic length at necropsy were recorded. Horses were assessed by physical examination every 6 h for 5 days after surgery, then once daily until euthanasia at 7 days. A group of seven horses that had a stapled side-to-side JC and were euthanized 28 days postoperatively was used as an historical control (SS). Results: All MS horse...
Frippiat T, Bonhomme M, Dyson S, Votion DM.Equine gastric ulcer syndrome (EGUS) adversely affects the health, welfare, and performance of sports horses, requiring gastroscopy for definitive diagnosis. Owners frequently consider girth aversion as highly suggestive of EGUS. Objective: To evaluate whether owner-reported clinical signs or fecal occult blood tests (FOBTs) can help identify horses needing gastroscopy for EGUS diagnosis or monitoring treatment, thereby reducing unnecessary procedures in unaffected horses. Methods: Eighty competition dressage horses referred by veterinarians for EGUS evaluation. Methods: Case-control study in...
