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.
Morsy K, Bashtar AR, Al Quraishy S, Adel S.Parasitic gastroenteritis (PGE) caused by infection of the gut with parasitic nematodes is one of the most important diseases of livestock animals from both financial and welfare perspectives. Parascaris equorum and Habronema microstoma are of the most endemic nematodes of the world which are currently the major cause of PGE of the domestic horses in Egypt. The present investigation introduced the first morphological description of these nematodes recovered from the domestic horse, Equus ferus caballus (Equidae), in Egypt by light and scanning electron microscopy. Seven P. equorum (fifth stage...
Wilson CS, Brookes VJ, Hughes KJ, Trope GD, Ip H, Gunn AJ.In human subjects, arytenoid chondritis can be caused by chemical trauma of mucosa attributable to gastro-oesophageal reflux. Although a similar process may be involved in the aetiopathogenesis of arytenoid chondritis in horses, the oesophageal lumen pH in this species is poorly understood. Objective: To determine if gastro-oesophageal reflux occurs in horses by characterising oesophageal lumen pH. Methods: Blinded, randomised, placebo-controlled, crossover, experimental study. Methods: Luminal oesophageal pH in six yearling horses was recorded over four 24 h periods using an ambulatory pH rec...
Mönki J, Hewetson M, Virtala AM.Equine gastric glandular disease (EGGD) is a term used to classify erosive and ulcerative diseases of the glandular mucosa of the equine stomach. Epidemiologic studies of risk factors for EGGD have not been reported. Objective: To determine risk factors for EGGD. Methods: Cases (n = 83) had endoscopic evidence of EGGD; controls (n = 34) included healthy horses and horses with equine squamous gastric disease (ESGD) without EGGD. Methods: Retrospective case-control study. The data were analyzed by multivariable logistic regression modeling. Analysis was performed on the full dataset. An addi...
Brownlow MA, Dart AJ, Jeffcott LB.Metabolic heat produced by Thoroughbred racehorses during racing can rapidly elevate core body temperature (1°C/min). When environmental conditions are hot and humid, the normal physiological cooling mechanisms become ineffective. The heat accumulated may exceed a critical thermal maximum (estimated to be 42°C), which may trigger a complex pathophysiological cascade with potentially lethal consequences. This syndrome has been labelled exertional heat illness (EHI). EHI is described in humans, but has not been well documented in Thoroughbred racehorses. The clinical signs described in racehor...
Edmunds JL, Worgan HJ, Dougal K, Girdwood SE, Douglas JL, McEwan NR.The present study uses in vitro analytical techniques to investigate the effect of activated charcoal on the microbial community of the equine hindgut and the metabolites they produce. Incubations were performed in Wheaton bottles using a 50 ml incubation of a high-energy feed or a low-energy feed, plus bottles with no added food source, together with five levels of activated charcoal (0, 10, 25, 50 or 100 mg per bottle) and fecal samples as a bacterial inoculum. Using this method the rate of gas production, volatile fatty acid and ammonia concentrations, and pH values were analyzed and found ...
van Bergen T, Wiemer P, Schauvliege S, Paulussen E, Ugahary F, Martens A.To evaluate the epiploic foramen using laparoscopy in horses previously treated for epiploic foramen entrapment to determine if spontaneous epiploic foramen closure had occurred. Methods: Non-consecutive case series. Methods: Seven horses. Methods: The epiploic foramen was inspected by right flank laparoscopy between 35 and 71 days after successful surgical treatment for epiploic foramen entrapment. Data were collected on the presence of behavior vices, details of surgery for epiploic foramen entrapment (time from colic onset to surgery, site and length of entrapped intestine, direction of ent...
Vondran S, Venner M, Vervuert I.Feeding alfalfa hay is often recommended for its buffering components, like protein and calcium, to prevent lesions of the gastric mucosa in horses. Until now, there has been no information regarding the influence of alfalfa particle size on the gastric mucosa. The aim of this study was to investigate the effects of feeding two alfalfa preparations with different particle sizes (alfalfa chaff vs alfalfa pellets) in comparison with grass hay on the gastric mucosa in weanling horses. We hypothesized that feeding a high proportion of fine alfalfa particles would negatively impact gastric mucosa a...
Coverdale JA.Intensive management practices in the horse industry present a unique challenge to the microbiome of the large intestine. Common management practices such as high-concentrate diets, low forage quality, meal feeding, and confinement housing have an impact on intestinal function, specifically large intestinal fermentation. The microbiome of the equine large intestine is a complex and diverse ecosystem, and disruption of microbiota and their environment can lead to increased incidence of gastrointestinal disorder. Digestion in the horse can be improved through a variety of approaches such as feed...
Julliand V, Grimm P.In the early 1990s, the equine hindgut microbial ecosystem looked like a "black box." Its vital role in hydrolyzing and fermenting fiber, thus providing energy to the host, was recognized. Although there was a critical lack of information on the hindgut microbes, their role in preventing intestinal diseases was suggested. Traditionally, the microbes of the horse hindgut were studied using culture-dependent techniques. More recently, culture-independent methods have been used and provided further insight. This review presents the history and updated knowledge regarding the microbes that live in...
Harlow BE, Lawrence LM, Hayes SH, Crum A, Flythe MD.Starch from corn is less susceptible to equine small intestinal digestion than starch from oats, and starch that reaches the hindgut can be utilized by the microbiota. The objective of the current study was to examine the effects of starch source on equine fecal microbiota. Thirty horses were assigned to treatments: control (hay only), HC (high corn), HO (high oats), LC (low corn), LO (low oats), and LW (low pelleted wheat middlings). Horses received an all-forage diet (2 wk; d -14 to d -1) before the treatment diets (2 wk; d 1 to 14). Starch was introduced gradually so that horses received 50...
Rötting AK, Freeman DE, Constable PD, Eurell JA, Wallig MA.OBJECTIVE To evaluate the eosinophilic response in intestinal mucosa of horses with intestinal ischemia and reperfusion or with strangulation of the jejunum or colon. SAMPLE Mucosal samples from horses with naturally occurring strangulation (n = 24 horses) or distention (n = 6) of the jejunum or colon (11), with experimentally induced ischemia and reperfusion of the jejunum (6) or colon (15), or that were euthanized for reasons other than gastrointestinal tract disease (13). PROCEDURES Mucosal samples were collected and grouped by type of intestinal injury. Slides were stained with Luna eosino...
Debeffe L, McLoughlin PD, Medill SA, Stewart K, Andres D, Shury T, Wagner B, Jenkins E, Gilleard JS, Poissant J.In wild and domestic animals, gastrointestinal parasites can have significant impacts on host development, condition, health, reproduction and longevity. Improving our understanding of the causes and consequences of individual-level variation in parasite load is therefore of prime interest. Here we investigated the relationship between strongyle fecal egg count (FEC) and body condition in a unique, naturalized population of horses that has never been exposed to anthelmintic drugs (Sable Island, Nova Scotia, Canada). We first quantified variation in FEC and condition for 447 individuals accordi...
Swerczek TW.Unexplained clinical signs of weight loss and emaciation were reported in a herd of Thoroughbred horses grazing spring pastures on a central Kentucky farm, even though supplemental grain and hay were provided. Results: A buttercup plant, Ranunculus bulbosus L, was abundantly present in all pastures and paddocks on the farm. All horses, especially lactating mares and their foals, had mild to severe weight loss as assessed by body condition. Seven mares on the farm had been confirmed pregnant between 30 and 45 days of gestation, but were later found to have aborted. Two 2-year-old fillies develo...
Hopster K, Wogatzki A, Geburek F, Conze P, Kästner SB.High airway pressures, necessary to keep equine lungs open, can have a detrimental impact on central and peripheral perfusion. Objective: The aim of this study was to assess the effects of stepwise increasing airway pressure recruitment on central and intestinal perfusion and oxygenation during isoflurane anaesthesia in horses. Methods: In vivo experimental study. Methods: Ten anaesthetised horses were ventilated using intermittent positive pressure ventilation immediately after induction. After 90 min, end-expiratory pressure (PEEP) was increased by steps of 5 cmH2 O every 10 min up to a PEEP...
Mullen KR, Yasuda K, Divers TJ, Weese JS.While certainly not a novel concept, faecal microbiota transplant (FMT) has recently garnered renewed interest in veterinary medicine due to its remarkable success in treating recurrent Clostridium difficile infection (CDI) in man. There is a dearth of information on indications and efficacy of FMT for the treatment of gastrointestinal disorders in the horse; however, based on evidence in man and other veterinary species, and anecdotal reports in horses, FMT may be a useful treatment for selected cases of acute and chronic diarrhoea and inflammatory bowel disease (IBD) in the horse. In the abs...
Mair TS, Sherlock CE, Fews D, Harley R, Pearson GR.Histological evidence of fibrosis affecting the outer layer of the large intestinal tunica muscularis was identified in five of 32 horses affected by colic. In three cases, foci of pale eosinophilia and vacuolation of myocytes were observed. These findings are suggestive of a degenerative and fibrotic abnormality in the outer layer of the tunica muscularis of the large intestinal smooth muscle of some horses with colic.
Mas M, Mañé N, Fernández F, Gallego D, Pumarola M, Jiménez M.In the equine large intestine, the knowledge of the basic mechanisms underlying motility function is crucial to properly treat motility disorders. P2Y1 receptors are responsible for mediating purinergic colonic relaxation in several species. In vitro experimental studies of the circular muscle from the equine pelvic flexure (n = 6) were performed to characterize inhibitory and excitatory neuromuscular transmission. Electrophysiological studies showed that electrical field stimulation (EFS) evoked biphasic inhibitory junction potentials (IJPs) in smooth muscle cells: a fast IJP (IJPf) follo...
Padalino B, Hall E, Raidal S, Celi P, Knight P, Jeffcott L, Muscatello G.Equine transportation is associated with a variety of serious health disorders causing economic losses. However; statistics on horse transport are limited and epidemiological data on transport related diseases are available only for horses transported to abattoirs for slaughter. This study analysed reports of transport related health problems identified by drivers and horse owners for 180 journeys of an Australian horse transport company transporting horses between Perth and Sydney (~4000 km) in 2013-2015. Records showed that 97.2% (1604/1650) of the horses arrived at their destination with no...
Guri A, Paligot M, Crèvecoeur S, Piedboeuf B, Claes J, Daube G, Corredig M, Griffiths MW, Delcenserie V.The aims of this study were to examine the effect of mare's milk on virulence gene expression of Salmonella Typhimurium and observe its potential activity on proliferation of adenocarcinoma Caco-2 cells. Different supernatants of mare's milk, raw or heat-treated at 65°C for 15 s or 30 min, were studied. The changes in hilA gene expression of Salmonella Typhimurium in presence of mare's milk supernatants were assessed using a reporter luminescent strain. A significant decrease in hilA gene expression was observed with all tested supernatants. Virulence gene expression was then assessed using q...
Costa MC, Stämpfli HR, Allen-Vercoe E, Weese JS.The intestinal microbiota is a complex polymicrobial ecosystem that exerts extremely important roles in the development and maintenance of health. Recently, as new sequencing technologies have become more available, there has been a revolution in the understanding of the equine intestinal microbiota. However, studies characterising the pioneer intestinal bacteria colonising foals and its development over time are still limited. Objective: The objectives of this study were to characterise the intestinal bacterial colonisation of newborn foals and to follow individual animals over time until age...
Damkel C, Snyder A, Uhlig A, Coenen M, Schusser GF.An electrode incorporated into a polyethylene hose was introduced under endoscopic control into the stomach of six fasting adult horses for long-lasting pH measurements. The intragastric pH was recorded every four seconds for a period of 24 hours. The Warmblood horses were assigned randomly to receive hay ad libitum (H group); 1.5 kg hay/100 kg BW/day and 1 kg concentrate/100 kg BW/ day (C group) or protocol C plus 75 g pectin-lecithin supplement/100 kg BW/day (P group). The horses were adapted to each diet for 14 days. The 24-hour median pH value for protocol H (2.69) was significantly lower ...
Lohmann KL, Allen AL.A mature Quarter horse was euthanized following colic of 3 days duration. Postmortem, the large intestine, except the descending colon, was diffusely distended and associated with adhesion of the transverse colon to the pancreas, which had changes consistent with chronic active interstitial pancreatitis. Other lesions included hepatic fibrosis, erosive gastritis, and bilateral adrenal cortical hyperplasia. Pancréatite interstitielle chronique active comme cause d’une obstruction du côlon transversal et de coliques chez un cheval. Un cheval Quarter horse adulte a été euthanasié après de...
Gomez DE, Radtke CL, Russell LA, Lopez A, Wichtel MW.Acute pancreatitis is a rare disease in horses and is often associated with gastrointestinal disorders. Accurate diagnosis is challenging due to the presence of nonspecific clinical signs. This case represents the first documentation of acute pancreatitis in a horse following surgery of the reproductive tract. La pancréatite aiguë est une maladie rare chez les chevaux et est souvent associée aux troubles gastro-intestinaux. Un diagnostic exact est difficile en raison de la présence de signes cliniques non spécifiques. Ce cas représente la première fois qu’une pancréatite aiguë est ...
Curtis L, Burford JH, Thomas JS, Curran ML, Bayes TC, England GC, Freeman SL.The majority of research on the evaluation of horses with colic is focused on referral hospital populations. Early identification of critical cases is important to optimise outcome and welfare. The aim of this prospective study was to survey the primary evaluation of horses with clinical signs of abdominal pain by veterinary practitioners, and compare the initial presentation of critical and non-critical cases. Results: Data from 1016 primary evaluations of horses presenting with clinical signs of colic were submitted by 167 veterinary practitioners across the United Kingdom over a 13 month p...
Curtis L, Trewin I, England GC, Burford JH, Freeman SL.The aim of this study was to survey veterinary practitioners' selection of diagnostic tests for horses with clinical signs of abdominal pain. A questionnaire was distributed to veterinary surgeons involved in the primary evaluation of horses with abdominal pain, including the respondent's demographics, selection of diagnostic tests and factors affecting decision-making. Data analysis included descriptive analysis, categorisation of free text and simple univariable correlations to explore the relationships between independent variables and the relative self-estimated frequency that diagnostic t...
Raftery AG, Morgan RA, MacFarlane PD.To compare perioperative trends in plasma colloid osmotic pressure (COP) between horses undergoing orthopedic and colic surgery. Methods: Prospective clinical study September 2009-January 2011. Methods: Veterinary university teaching hospital. Methods: Thirty-three healthy, client-owned horses presenting for orthopedic surgery (non-GI) and 85 client-owned horses presenting for emergency exploratory celiotomy (GI, gastrointestinal). Methods: None. Methods: Data relating to the horse's parameters on presentation, surgical lesion, post-operative management and survival were extracted from compute...
Lotstra RJ, van den Broek J, Power T, Marr CM, Wijnberg ID.Atrial fibrillation is a common equine arrhythmia. Quinidine alone, or with digoxin are common treatments. Studies on outcome in Warmblood populations in which duration of the AF is often unknown are limited. Objective: To identify the factors that are associated with the success of full treatment cardioversion with oral medication, and establish whether there are differences in these factors between institutions. Methods: Retrospective case series using patient records of Equine University Clinic of Utrecht University and Rossdales Equine Hospital, Newmarket. Methods: Forty-nine horses treate...
Delesalle CJ, Callens C, Van Colen I, Lefebvre RA.Selective 5-HT4 receptor agonists such as prucalopride are used as human prokinetics, since activation of 5-HT4 receptors on intestinal cholinergic neurons facilitates acetylcholine release. 5-HT4 receptors, linked to adenylyl cyclase, act via generation of cAMP. None of the 4 in vitro studies on 5-HT in horses provided evidence for neuronal 5-HT4 receptors, but none used the protocol as described in human studies [1-4]. Objective: To investigate whether functional 5-HT4 receptors are present in the equine small intestine. Methods: In vitro organ bath set up, applying electrical field stimulat...
Rodriguez C, Taminiau B, Brévers B, Avesani V, Van Broeck J, Leroux A, Gallot M, Bruwier A, Amory H, Delmée M, Daube G.The equine faecal microbiota is very complex and remains largely unknown, while interspecies interactions have an important contribution to animal health. Clostridium difficile has been identified as an important cause of diarrhoea in horses. This study provides further information on the nature of the bacterial communities present in horses developing an episode of diarrhoea. The prevalence of C. difficile in hospitalised horses at the time of admission is also reported. Results: Bacterial diversity of the gut microbiota in diarrhoea is lower than that in non-diarrhoeic horses in terms of spe...
Dukti SA, Perkins S, Murphy J, Barr B, Boston R, Southwood LL, Bernard W.Prevalence of gastric ulcerations differs widely according to breed and circumstances of management. Further study of the biological variables involved is required in order to identify more exactly the reasons for the reported range. Objective: The objectives of this present study, which do not appear to have been addressed previously in the literature, were 1) the prevalence of gastric ulceration in horses with abdominal pain. 2) difference in prevalence in horses responding to medical therapy and those requiring surgical intervention. 3) whether gastric ulceration is associated with any part...
Cooke CG, Gibb Z, Harnett JE.Probiotic bacteria are used widely as nutritional supplements and treatment interventions in the management of livestock and companion animals. The aim of this review is to summarize the current evidence reporting on the safety, tolerability and efficacy of probiotic bacteria use in horses. An online search of five databases for studies reporting on the use of probiotic bacteria use in horses which were either healthy or had a gastrointestinal or extraintestinal disease was conducted. A total of 18 articles were eligible for full review. No clear benefits were identified to support supplementa...
Bush J, van den Boom R, Franklin S.Anecdotally, aloe vera is used to treat gastric ulceration, although no studies have yet investigated its efficacy in horses. Objective: To test the hypothesis that aloe vera would be noninferior to omeprazole in the treatment of equine gastric ulcer syndrome. Methods: Randomised, blinded clinical trial. Methods: Forty horses with grade ≥2 lesions of the squamous and/or glandular mucosa were randomly assigned to one of two groups. Horses received either aloe vera inner leaf gel (17.6 mg/kg bwt) b.i.d. or omeprazole (4 mg/kg bwt) s.i.d. for approximately 28 days, after which a repeat gastrosc...
Sykes BW, Sykes KM, Hallowell GD.Interest in Equine Gastric Ulcer Syndrome (EGUS) has recently increased in part due to a growing awareness of the differences between squamous and glandular disease. The pathophysiology and epidemiology of squamous and glandular disease are different and recently it has been shown that the response of glandular gastric ulceration to monotherapy with omeprazole is poor. Given these differences it has been recommended that specific treatment guidelines be formulated for equine glandular disease and that adjunctive therapies be investigated. Along these lines it has been suggested that the additi...
Lisowski ZM, Pirie RS, Blikslager AT, Lefebvre D, Hume DA, Hudson NPH.Post-operative ileus (POI) is a serious condition which any horse undergoing abdominal surgery is at risk of developing, leading to increased hospitalisation time and resulting costs. Advances in the understanding of the development of equine POI are mainly based on human and rodent literature, where manipulation-induced inflammation has been identified as a trigger, with activation of resident muscularis externa macrophages playing a crucial role in the pathophysiology. Despite many pharmacological trials in all species, there is no single completely successful treatment for POI, highlighting...
Nelson BB, Lordan EE, Hassel DM.Gastrointestinal dysfunction occurs commonly following elective anaesthesia. Identification of risk factors may allow implementation of preventative measures to reduce the prevalence of colic following elective anaesthetic procedures. Objective: To examine risk factors associated with gastrointestinal dysfunction or post anaesthetic colic for horses undergoing elective surgical or diagnostic procedures under general anaesthesia. Methods: Retrospective case series. Methods: Medical records were collected from adult horses undergoing general anaesthesia from 1 January 2008 to 31 December 2010 us...
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...
Argenzio RA, Stevens CE.Effects of diet and time after feeding on osmolality and inorganic ion content of gastrointestinal digesta were studied in 24 ponies. Animals, fed either a conventional or a low-protein, high-cellulose diet, were sacrificed 2, 4, 8, or 12 h after a meal. Animals fed the conventional diet showed cyclic variations in the ionic composition and osmolality of digesta with time after feeding. The most marked variations were seen in the contents of the stomach and small colon. However, results also indicated a cyclic appearance and disappearance of Na in large intestinal contents that correlated with...
Reed SK, Messer NT, Tessman RK, Keegan KG.To assess effects of treatment with phenylbutazone (PBZ) or a combination of PBZ and flunixin meglumine in horses. Methods: 24 adult horses. Methods: 13 horses received nonsteroidal antiinflammatory drugs (NSAIDs) in a crossover design. Eleven control horses were exposed to similar environmental conditions. Treated horses received PBZ (2.2 mg/kg, PO, q 12 h, for 5 days) and a combination of PBZ and flunixin meglumine (PBZ, 2.2 mg/kg, PO, q 12 h, for 5 days; flunixin meglumine, 1.1 mg/kg, IV, q 12 h, for 5 days). Serum samples were obtained on day 0 (first day of treatment) and day 5, and total...
Cargile JL, Burrow JA, Kim I, Cohen ND, Merritt AM.The effect of corn oil (approximately 60% [wt/vol] linoleic acid) dietary supplementation on various components of equine gastric secretion was studied by use of a repeated-measures experimental design. Four healthy adult ponies were surgically fitted with gastric cannulas. The ponies were then fed a free-choice hay diet for 5 weeks, which was followed by 5 weeks of the same diet supplemented with 45 mL of corn oil daily. Gastric contents were analyzed under basal and pentagastrin-stimulated conditions once weekly during the latter 2 weeks on each diet. Gastric contents were collected at 30-mi...
Mason LV, Moroney JR, Mason RJ.Guidelines regarding the impact and value of prophylaxis or maintenance therapy in equine gastric ulcer syndrome (EGUS) are not well-established or defined. The merits and the magnitude of effects of prophylaxis for spontaneous or recurrent squamous gastric ulceration in horses in training are uncertain. Objective: To pool data from randomised controlled trials (RCTs) to eliminate reporting bias and evaluate the efficacy of prophylactic omeprazole in the prevention of EGUS in training horses, and secondarily to compare prophylactic dosages of omeprazole. Methods: Meta-analysis. Methods: This m...
Kohn CW, Muir WW.Comparison of the visceral analgesic effects of xylazine, morphine, butorphanol, pentazocine, meperidine, dipyrone, and flunixin in a cecal distention model of colic pain indicated that xylazine produces the most relief from abdominal discomfort. Repeated administration of xylazine may reduce visceral pain so effectively that the seriousness of abdominal disease is obscured. Xylazine decreased propulsive motility in the jejunum and pelvic flexure of healthy ponies. Morphine and butorphanol also gave relief from visceral pain in the cecal distention model. Morphine may inhibit colonic, and buto...
Birkmann K, Junge HK, Maischberger E, Wehrli Eser M, Schwarzwald CC.GastroGard, an omeprazole powder paste formulation, is considered the standard treatment for gastric ulcers in horses and is highly effective. Gastrozol, an enteric-coated omeprazole formulation for horses, has recently become available, but efficacy data are controversial and sparse. Objective: To investigate the efficacy of GastroGard and Gastrozol at labeled doses (4 and 1 mg of omeprazole per kg bwt, respectively, PO q24h) in healing of gastric ulcers. Methods: 40 horses; 9.5 ± 4.6 years; 491 ± 135 kg. Methods: Prospective, randomized, blinded study. Horses with an ulcer score ≥1 (Equi...
Dowdall SM, Proudman CJ, Love S, Klei TR, Matthews JB.Cyathostomins are important equine gastrointestinal parasites. Mass emergence of mucosal stage larvae causes a potentially fatal colitis. Mucosal stages are undetectable non-invasively. An assay that would estimate mucosal larval stage infection would greatly assist in treatment, control and prognosis. Previously, we identified two putative diagnostic antigens (20 and 25 kDa) in somatic larval preparations. Here, we describe their purification and antigen-specific IgG(T) responses to them. Western blots confirmed the purity of the antigens and showed that epitopes in the 20 kDa complex were sp...
Zannoni A, Bombardi C, Dondi F, Morini M, Forni M, Chiocchetti R, Spadari A, Romagnoli N.Proteinase-activated receptor 2 (PAR2) is a G-protein-coupled receptor for trypsin and mast cell tryptase; it is highly expressed at the intestinal level with multiple functions, such as epithelial permeability and intestinal motility. Many proteases activate PAR2 during tissue damage, suggesting a role of the inflammatory response receptors. The aim of the study was to evaluate the distribution and expression of PAR2 in the jejunum, the ileum and the pelvic flexure, using samples collected from healthy adult horses after slaughter. Proteinase-activated receptor 2 immunoreactivity (PAR2-IR) wa...
Doherty TJ, Andrews FM, Provenza MK, Frazier DL.Gastric emptying was evaluated in ponies using the acetaminophen (AP) method. Fifteen minutes after i.v. administration of metoclopramide, erythromycin, yohimbine, atropine or saline, the ponies were given AP by stomach tube. Blood samples for AP analysis were collected at baseline and 15, 30, 45, 60, 75, 90, 105 and 120 min after AP administration. Time to reach peak serum concentration (Tmax), maximum serum concentration (Cmax) and area under the AP serum concentration vs. time curve (AUC) were determined for each treatment group. In the control group, Tmax was 31 min and this decreased sign...
Andrews FM, Buchanan BR, Elliott SB, Al Jassim RA, McGowan CM, Saxton AM.Volatile fatty acids, byproducts of carbohydrate fermentation by resident bacteria, have been implicated in causing nonglandular (NG) gastric ulcers. Lactic acid (LA), also produced by stomach bacteria, may cause gastric ulcers when exposed to the equine NG mucosa. Objective: To investigate the in vitro effects of LA on equine NG mucosa bioelectric properties, sodium transport and tissue resistance. Methods: Gastric tissues obtained from 13 mature horses were studied in Ussing chambers. Short-circuit current (Isc) and potential difference (PD) were measured, and electrical resistance (R) and c...
Voigt A, Saulez MN, Donnellan CM, Gummow B.The most common causes of gastrointestinal colic at an equine referral hospital in South Africa were determined following retrieval of the medical records of horses admitted during a 10-year study period. The study included 935 horses of which 28% were admitted after hours. Most horses were Thoroughbreds (54%), male (57%), with a mean age of 8.2 years and originated from the Gauteng Province (81%). Heart rate (98%), mucous membrane colour (95%) and auscultation of the abdomen (91%) were the clinical data commonly obtained at admission. Packed cell volume, total serum protein and white cell cou...
Ramalho Sousa S, Anastácio S, Nóvoa M, Paz-Silva A, Madeira de Carvalho LM.In Portugal, equine parasitism in pasture animals is characterized by high parasitic burden and high helminthic biodiversity; both factors are potentially pathogenic for their hosts. The decrease in the number of donkeys over the last years in Portugal, their importance in rural lowland and mountain ecosystems and pastures and the scarce information regarding their parasitism led to this research, which aimed to evaluate the parasitological status of a Miranda donkey breed population, a native breed mainly located in the northeast of Portugal. This study provides better knowledge of their gast...
Tapio H, Raekallio MR, Mykkänen A, Männikkö S, Scheinin M, Bennett RC, Vainio O.Medetomidine suppresses cardiovascular function and reduces gastrointestinal motility in horses mainly through peripheral α -adrenoceptors. Vatinoxan, a peripheral α -antagonist, has been shown experimentally to alleviate the adverse effects of some α -agonists in horses. However, vatinoxan has not been investigated during constant-rate infusion (CRI) of medetomidine in standing horses. Objective: To evaluate effects of vatinoxan on cardiovascular function, gastrointestinal motility and on sedation level during CRI of medetomidine. Methods: Experimental, randomised, blinded, cross-over stud...
Gardner RB, Nydam DV, Mohammed HO, Ducharme NG, Divers TJ.The purpose of this study was to test the hypothesis that horses with right dorsal displacement of the large colon (RDDLC) have elevations in serum gamma glutamyl transferase (GGT) activity when compared with horses with left dorsal displacement of the large colon (LDDLC). Medical records from 37 horses with RDDLC and 48 horses with LDDLC were reviewed. Horses were included for study if the RDDLC or LDDLC was confirmed by exploratory laparotomy or postmortem examination and if a serum GGT measurement was obtained within 24 hours before surgery. The proportion of horses with GGT activity within...
Tesena P, Yingchutrakul Y, Roytrakul S, Taylor J, Angkanaporn K, Wongtawan T.Equine squamous gastric disease (ESGD) is a very common disorder but an accurate and practical screening technique for detecting ESGD is currently lacking. Objective: To identify serum protein markers to detect ESGD using electrophoresis and mass spectrometry. Methods: Proteomic analysis and bioinformatics. Methods: ESGD was diagnosed using gastroscopy in 30 horses. Gastric ulceration was categorised into three groups: normal, mild/moderate and severe ESGD. Pooled sera from each group were compared using 1D electrophoresis and mass spectrometry. The candidate proteins for ESGD markers were sel...
Packer M, Patterson-Kane JC, Smith KC, Durham AE.The histological diagnosis of inflammatory bowel disease (IBD) in horses and other species is subjective, and pathological assessments vary considerably as a result. One important criterion is increased infiltration of the lamina propria by eosinophils, plasma cells, lymphocytes or macrophages, but this is difficult to assess without a knowledge of the normal immune cell populations and potential for individual variation. Retrospective jejunal specimens were analysed from 14 horses aged 13-15 years which had not shown clinical or post-mortem signs of gastrointestinal disease. Populations of pl...
Imani-Baran A, Abdollahi J, Akbari H, Jafarirad S, Moharramnejad S.Trachyspermum ammi has been used traditionally as a popular ethnobotanical plant in human and animal parasitic infestations. Few scientific studies have been conducted on in vitro anthelmintic activity of T. ammi against various helminths and there is no study on its in vivo/in vitro anthelmintic properties against equine helminths. Objective: The present study aimed to evaluate in vivo anthelmintic activity of crude powder (CP) and crude aqueous extract (CAE) of T. ammi seeds against gastrointestinal nematodes in the donkey. Methods: Thirty donkeys, naturally and severely infected with Stro...
Bell RJ, Kingston JK, Mogg TD.To compare two scoring systems for grading gastric ulcers in adult horses. Methods: Digitised recordings of gastroscopy examinations of 22 horses that were part of a study on prevalence of gastric ulceration in racehorses in New Zealand were reviewed independently by three examiners. All stomachs were graded by each examiner using two different grading systems, the Equine Gastric Ulcer Council (EGUC) system and the Number/Severity (N/S) system. Results: All examiners commented that the EGUC system was quicker and easier to use. There was no significant difference between examiners in the grade...
Sheats MK, Cook VL, Jones SL, Blikslager AT, Pease AP.The post operative response of the large colon wall after a surgically corrected large colon volvulus (LCV) has not been investigated. Objective: To use transabdominal ultrasound to monitor the post operative change in large colon wall thickness following surgical correction of LCV. Objective: A prolonged period to colon wall involution is correlated with an increased rate of post operative morbidity and mortality. Methods: A prospective clinical study including horses that presented to the North Carolina State University Veterinary Teaching Hospital for colic between September 2006 and March,...
Videla R, Sommardahl CS, Elliott SB, Vasili A, Andrews FM.Gastric ulcers are common in horses and treatment of horses that cannot be administered oral medication can be problematic. Objective: To evaluate the efficacy of esomeprazole sodium administered intravenously on gastric juice pH and gastric ulcer scores in horses. Methods: Twelve adult female Quarter Horses. Methods: Esomeprazole sodium (0.5 mg/kg IV) was administered once daily to 8 horses (treatment group) and saline (5 mL IV) was administered to 4 horses (control group) for 13 consecutive days. Gastroscopy was performed and gastric juice pH and gastric ulcer score were recorded before and ...
Plummer AE.Impactions of the small and large intestines are frequently diagnosed as the cause of colic in horses. An impaction is an accumulation of dehydrated ingesta in a portion of the digestive tract, typically at sites where the intestinal diameter decreases. The specific pathogenesis for impactions is not fully understood, although risk factors have been identified for several types of impactions. Treatment for impactions includes withholding feed until the impaction passes, rehydrating the ingesta, and, if necessary, administering analgesic agents. In severe cases, surgery may be necessary to reli...
Tessier C, Pitaud JP, Thorin C, Touzot-Jourde G.There are no data investigating the effect of systemic morphine on the size of the stomach or the food consumption in horses. Objective: To evaluate gastrointestinal side effects of morphine administered systemically in healthy horses by the means of clinical and ultrasonographic evaluations. Methods: In vivo experiment. Methods: On day 1 of the experiment, six healthy French Trotter mares were evaluated clinically and an abdominal ultrasonography was performed three times 4 h apart to record the size of the stomach, the number of contractions per minute of the duodenum, jejunum, caecum, left...
Jones SL, Davis J, Rowlingson K.To determine whether ultrasonography would be useful in the diagnosis of right dorsal colitis in horses. Methods: Retrospective study. Methods: 5 horses with right dorsal colitis and 15 healthy adult horses. Methods: Mural thickness and appearance of the right dorsal colon were determined from ultrasonographic images obtained at right intercostal spaces 10, 11, 12, 13, and 14. Results: The right dorsal colon could be imaged most consistently at the right 11th, 12th, and 13th intercostal spaces, below the margin of the lung and axial to the liver. Mural thickness measured from ultrasonographic ...
