The intestines in horses are a vital component of the digestive system, responsible for nutrient absorption and waste elimination. The equine intestinal tract is divided into the small intestine and the large intestine, each playing distinct roles in digestion. The small intestine is involved in the enzymatic breakdown and absorption of proteins, fats, and carbohydrates. The large intestine, consisting of the cecum, colon, and rectum, is primarily responsible for fermenting fibrous plant material, producing volatile fatty acids, and absorbing water. The structure and function of the intestines are influenced by diet, health status, and management practices. This page compiles peer-reviewed research studies and scholarly articles that explore the anatomy, physiology, and health challenges associated with the equine intestines, including colic, intestinal motility disorders, and microbial balance.
Moll HD, Juzwiak JS, Santschi EM, Slone DE.Volvulus of the small intestine was diagnosed as a complication of acquired inguinal herniation in 2 horses. One of the horses continued to have signs of pain after reduction of the hernia. The volvulus was diagnosed at a second surgery, but the intestine was devitalized, and the horse was euthanatized. Ventral midline exploratory surgery was performed on the second horse, in conjunction with an inguinal approach. The small-intestinal volvulus was diagnosed and corrected at this time. It is suggested that ventral midline abdominal exploration be performed when acquired inguinal herniation caus...
Welles EG, Prasse KW, Moore JN.Protein C content and plasminogen activity were measured in plasma from 100 horses with signs of colic. Data were analyzed by grouping horses 4 ways. Each horse was allotted to 1 of 2 outcome groups (survivors and nonsurvivors), 1 of 3 broad-category diagnosis groups (inflammatory disorders, strangulating obstructions, and all other gastrointestinal disorders), and 1 of 2 clinical management groups (medical and surgical). In a fourth grouping, all horses (although numbers of horses included in each subgroup were small) were assigned either to specific diagnostic groups that had high expectatio...
Simmons TR, Gaughan EM, Ducharme NG, Dill SG, King JM, Anderson WI.Excessive administration of phenylbutazone was associated with development of right dorsal ulcerative colitis. The clinical signs of right dorsal colitis include chronic colic and weight loss. The laboratory abnormalities include panhypoproteinemia and a high WBC count in the abdominal fluid. Medical management of the chronic colic and protein-losing enteropathy associated with the ulcerative lesions in the right dorsal colon and surgical bypass of the right dorsal colon did not result in long-term resolution of clinical signs. Resection of the ulcerated right dorsal colon through a right late...
Dierckins MS, Sherman DM, Gendron-Fitzpatrick A.A presumptive diagnosis of paratuberculosis was made in a Sicilian ass on the basis of a history of chronic diarrhea and weight loss, pasture exposure to a heifer with paratuberculosis confirmed by bacterial culture of feces, postmortem identification of granulomatous inflammation of the intestine containing acid-fast organisms, the absence of acid-fast organisms in extraenteric tissues, and the absence of exposure to tuberculosis. The literature on paratuberculosis in equids is reviewed. The potential for cross-species transmission is emphasized. Justification for consideration of Mycobacteri...
Merighi A, Kar S, Gibson SJ, Ghidella S, Gobetto A, Peirone SM, Polak JM.The distribution of calcitonin gene-related peptide (CGRP), enkephalin, galanin, neuropeptide Y (NPY), somatostatin, tachykinins and vasoactive intestinal polypeptide (VIP) was compared in cervical, thoracic, lumbar and sacral segmental levels of spinal cord and dorsal root ganglia of horse and pig. In both species, immunoreactivity for the peptides under study was observed at all segmental levels of the spinal cord. Peptide-immunoreactive fibres were generally concentrated in laminae I-III, the region around the central canal, and in the autonomic nuclei. A general increase in the number of i...
Belknap JK, Moore JN.The records of 71 horses with small intestinal disorders requiring surgical correction were disorders requiring surgical correction were reviewed to compare the prevalence of laminitis in those horses treated prophylactically with heparin and the prevalence of horses not treated with heparin. The prevalence of laminitis was 13% (9/71), and there was no significant difference (P less than 0.05) in the prevalence of laminitis between the 2 groups. The lack of significant benefit after treatment with heparin indicates that further work needs to be done on the equine coagulation system before hepa...
Stick JA, Loeffler BS, Arden WA, Chou CC.The effects of butorphanol tartrate on arterial pressure, jejunal blood flow, vascular resistance, oxygen extraction, and oxygen uptake were determined in 10 anesthetized ponies ventilated with a mixture of halothane and 100% oxygen, using isolated autoperfused jejunal segments. Physiologic saline solution or butorphanol tartrate (0.2 mg/kg of body weight) was administered as a single bolus into the left jugular vein. By 2 minutes, butorphanol decreased arterial blood pressure and intestinal blood flow, and increased intestinal oxygen extraction. However, intestinal vascular resistance and oxy...
Allen D, Swayne D, Belknap JK.The clinical signs, medical and surgical management, and pathological findings are described for a ganglioneuroma, an atypical intestinal tumor, that caused colic because of small intestinal obturation.
Schmidt AR.A 5-MHz transducer was used transrectally to image palpable structures in the caudal portion of abdominal and pelvic cavities of 12 horses. In 8 healthy horses, structures scanned transrectally included the left kidney, spleen, urinary bladder, urethra, accessory sex organs in the male, portions of the intestinal tract, caudal portion of the aorta, and iliac arteries, and, in small horses, the cranial mesenteric artery. The transrectal technique was used to evaluate these structures in 4 horses with clinical signs indicating intrapelvic or intra-abdominal disease. Seemingly, transrectal ultras...
Green P, Tong JM.Although wood chewing by horses is recognised as a common vice, there are few reports of specific disease associated with the habit. Two cases of acute obstruction of the small intestine by solid aggregations of wood splinters are described in horses which were both habitual wood chewers. Details are presented of the clinical findings in these cases, including the surgical treatment of acute colic. Both horses returned to full working fitness. The authors review the syndrome of enterolithiasis in horses, and discuss the causes and significance of wood chewing as a stable vice.
Orsini JA, Orsini PG, Sepesy L, Acland H, Gillette D.Intestinal carcinoid, or argentaffinoma, should be an etiologic consideration for horses with chronic colic. A mare was referred with a history of chronic colic. Previously, the signs of colic had subsided in response to impiric treatment, but recent episodes of colic did not. Clinical signs and results of physical examination supported the finding of strangulating obstruction of the small intestine. Exploratory celiotomy revealed internal herniation with simultaneous volvulus of the jejunum and accompanying carcinoid.
Rose J, Rose E.This article discusses some of the rationales for the medical management of colic during the initial treatment period. The issue of colic pain control and the masking of clinical signs that may indicate severe gastrointestinal disease is addressed. Therapeutic considerations related to dehydration, metabolic imbalances, hemostatic disorders, antimicrobial therapy, fecal consistency, gastrointestinal decompression, and regulation of intestinal motility are reviewed.
Kobluk CN, Smith DF.An intramural hematoma involving a 40-cm segment of the distal portion of the jejunum caused intestinal obstruction and colic in a mature mare. The involved intestine was resected, and an end-to-end anastomosis was performed. The mare recovered completely, but 4 years later had colic caused by incarceration and volvulus of the distal portion of the jejunum, involving fibrous abdominal adhesions. The cause of hematoma was not identified; however, rupture of an intramural vessel after migration of Strongylus vulgaris larvae was considered a possibility because of the histologic observation of an...
Johnston JK, Morris DD.Sixty-eight horses with colic caused by small intestinal disease were allotted into 2 groups of 34 on the basis of recorded findings during exploratory celiotomy, necropsy, or response to medical treatment alone. Signalment, history, physical examination findings, and laboratory findings were compared between the group of horses with small intestinal obstruction and the group with duodenitis/proximal jejunitis. A significantly greater proportion of horses with duodenitis/proximal jejunitis were older than 2 years old (P less than 0.05). Differences in sex or breed distribution, or in seasonali...
Gossett KA, Cleghorn B, Adams R, Church GE, McCoy DJ, Carakostas MC, Flory W.Increased anion gap (AG) was due, in part, to L-lactic acidosis in 14 of 14 horses with intestinal disorders. In a few horses, increased whole blood concentrations of D-lactate made a minor contribution to the AG. However, the increase in AG was often greater than the sum of the increases in these 2 acid anions. This unexplained increase was not a result of increases in whole blood pyruvate, 3-hydroxybutyrate, or acetoacetate concentrations or serum albumin or phosphate concentrations. Identification of other anions causing increased AG could lead to better understanding, diagnosis, and treatm...
Platt H.A series of 9 cases of primary diffuse alimentary lymphoma of the equine small intestine is described. Clinically, the principal effects were attributable to malabsorption and disordered alimentary function and several cases had severe anaemia; in four this was of the haemolytic type. Hypoalbuminaemia and elevated gamma globulin levels were often present. The neoplasms were confined mainly to the small intestine and mesenteric lymph nodes, sometimes with some involvement of other lymph nodes as well. The large bowel was affected in one horse, but none of the cases showed detectable invasion of...
Platt H.A retrospective study was made of 20 horses with severe and extensive chronic disease of the small intestine. Many of the animals had clinical evidence of malabsorption, with progressive loss of weight, hypoalbuminaemia and sometimes anaemia. All but two of the horses were Thoroughbreds. The pathology was diverse. Nine of the cases were alimentary lymphomas (Platt, 1986) and five had lymphocytic and eosinophilic infiltrations in the bowel wall which were considered to be probable reactions to parasitic invasion. One had acute thrombosis associated with partial occlusion of the anterior mesente...
Ward AC, Sriranganathan N, Evermann JF, Traub-Dargatz JL.Escherichia coli was isolated from the feces and intestines of foals with and without diarrhea. Piliation of isolates was demonstrated by electron microscopy and agglutination in antisera having specificity for K88, K99, P987 and F41 pili. Piliation was also demonstrated by electron microscopy on organisms which did not react with any of the antisera.
Merritt T, Mallonée PG, Merritt AM.Seven healthy foals (five ponies and two horses) were maintained on grass pasture with their dams. All foals had normal faeces at the time of testing. An oral xylose absorption test was performed on each foal at one, two and three months of age. Following an 8 h fast, 0.5 g/kg D-xylose as a 10 per cent solution was given via a nasogastric tube. Control and 30 min interval plasma samples were collected for 3 h and the plasma was analysed for xylose using the phloroglucinol microassay technique. Maximum xylose concentration levels were reached between 30 and 60 mins for each of the foals. The me...
Manohar M, Goetz TE.Blood flow to the brain, kidneys, adrenal glands, pancreas, and small intestine was studied in 8 healthy ponies while awake (control) and during 1.0, 1.5, and 2.0 minimal alveolar concentrations (MAC) of anesthesia produced, using halothane vaporized in oxygen. During the anesthesia steps, intermittent positive-pressure ventilation was used to ensure isocapnia. Organ blood flow was determined with 15-micron (diameter) radionuclide-labeled microspheres, after allowing 30 minutes of equilibration at each of the 3 preestablished end-tidal halothane concentrations. The sequence of 1.0, 1.5, and 2....
Davies JV, Gerring EL.Small intestinal ischaemia is a cause of pain in man and horses. Occlusion of the vascular supply to Thiry loops in experimental ponies caused severe discomfort and loss of motility within a few minutes but these effects could not be reproduced by a similar procedure in intact gut preparations. However, embolisation of the mural vascular network produced ischaemia of the small intestine of anaesthetised ponies which led to a cessation of motility in the affected segments, though unaffected segments became hypermotile with a characteristic motility pattern. These results suggest the need for re...
Lyons ET, Tolliver SC, Drudge JH, Swerczek TW, Crowe MW.A total of 89 Thoroughbreds, 14 to 333 days old (born in 1982), were examined at necropsy for certain internal parasites during a 1-year-period, Mar 1, 1982, to Feb 28, 1983. The eyes of 73 of the horses and the cranial mesenteric arteries of 71 were examined. Specific interest was on prevalence of parasites according to month of the year and age of the horses at necropsy. Parasites recovered (first month-last month infected horse found) were as follows: Thelazia lacrymalis (eyes) immature and mature (June - February); Habronema/Draschia (lungs) immature (May - September); Habronema muscae (st...
Turner TA, Adams SB, White NA.Fifteen horses were referred to Purdue University or to the University of Georgia because of colic. Each of these horses had small intestine incarcerated through the epiploic foramen. However, signs of pain, gastric reflux, and small intestine distention were not consistent signs, as would have been expected with small intestine strangulation/obstruction. In 10 of the 15 cases, abdominal fluid analysis provided the decisive information needed for surgical intervention. Surgery was performed in 14 cases. The small intestine was incarcerated through the epiploic foramen in a right-to-left direct...
Kitamura N, Yamada J, Calingasan NY, Yamashita T.Endocrine cells immunoreactive for somatostatin, gastrin, glicentin, glucagon, secretin, cholecystokinin, motilin and neurotensin were identified immunocytochemically in the gastrointestinal mucosa of the horse. Somatostatin-, glicentin- and glucagon-immunoreactive cells were very numerous in the cardiac and fundic regions of the stomach, whereas most gastrin-immunoreactive cells were confined to the pyloric region. Somatostatin-immunoreactive cells also were detected in all portions of the small intestine while gastrin-immunoreactive cells were confined exclusively to the upper portion and gl...
Roberts MC.Vitamin B12 and folate concentrations were determined by radioimmunoassay in groups of horses in Queensland. Highest serum vitamin B12 levels were found in supplemented performance horses. These, together with pastured horses that included pregnant and lactating mares, had significantly greater serum folate activity than permanently stabled animals. The range of red cell folate concentrations was much narrower in horses in training than from any other group. Red cell folate may be a better indicator of a horse's folate status than the serum folate value. Vitamin B12 and folate concentrations w...
Argiroudis SA, Kent JE, Blackmore DJ.The isoenzymes of creatine kinase have been measured in serum and selected tissues from horses. The distribution followed that reported in other species in that the MM dimer of the isoenzyme was present in voluntary and non-voluntary muscle, thyroid, liver, spleen, lung and intestine. The BB dimer of the isoenzyme was predominant in brain, pancreas, kidney, intestine, lung, spleen, liver and thyroid. In contrast, in 4 hearts examined less than 1.5 per cent of the total creatine kinase activity was attributable to the MB form of the isoenzyme. The MB isoenzyme was, however, present in intestine...
Johnston JK, Morris DD.Sixty-eight horses with colic caused by small intestinal disease were allotted into 2 groups of 34 on the basis of recorded findings during exploratory celiotomy, necropsy, or response to medical treatment alone. Signalment, history, physical examination findings, and laboratory findings were compared between the group of horses with small intestinal obstruction and the group with duodenitis/proximal jejunitis. A significantly greater proportion of horses with duodenitis/proximal jejunitis were older than 2 years old (P less than 0.05). Differences in sex or breed distribution, or in seasonali...
Gayle JM, Blikslager AT, Bowman KF.To describe the clinical findings in horses with small intestinal strangulation through mesenteric rents, and to determine the recurrence and survival rates after surgery. Methods: Retrospective study. Methods: 15 horses with small intestinal obstruction via a mesenteric rent. Methods: Medical records of horses with obstruction of the small intestine via a mesenteric rent between January 1990 and December 1997 were reviewed. The signalment, history, initial physical examination findings, results of abdominocentesis, and clinical laboratory values were recorded. Surgical findings, including loc...
Menozzi A, Pozzoli C, Poli E, Dacasto M, Giantin M, Lopparelli RM, Passeri B, Zullian C, Gobbetti T, Bertini S.We investigated the effects of nonselective cyclooxygenase (COX) inhibitors (indomethacin and flunixin meglumine) and selective COX-1 (SC-560) or COX-2 (celecoxib, DUP-398 and NS-697) inhibitors on horse small bowel motility in vitro. At this purpose, samples of equine ileum were put in isolated organ baths for the motility experiments. Nonselective COX inhibitors were devoid of major effects on motility, except for an inhibition of tonic contraction shown by flunixin meglumine. SC-560, selective COX-1 inhibitor, was devoid of significant effects on ileal motility. Selective COX-2 inhibitors r...
Lester GD, Bolton JR, Thurgate SM.Extracellular myoelectric activity from the terminal ileum, cecum, and colonic pelvic flexure was assessed in 4 adult horses. The collection and analysis of myoelectric data involved the development and use of a computer-based system. After collection, the myoelectric signal was digitally filtered to enhance the activity of interest. The smoothed signal was then processed by use of computer programs designed to identify and count spike-burst activity and estimate burst duration. The intense phases of myoelectric complexes also were identified. The propagation of myoelectric spike-burst activit...
Talbot SE, Tallon R, Dunkel B.Gastric impactions (GI) have been identified as primary lesions (lone GI; LGI) or associated with other intestinal lesions (concurrent GI; CGI). Anecdotally, CGI resolve more rapidly with a better prognosis than LGI. Objective: To determine clinical, laboratory, and ultrasonographic findings, and short- and long-term survival in horses with GI. We hypothesized that LGI carries a worse prognosis than CGI. Methods: Seventy-one horses from 2 referral hospitals (2007-2022). Methods: Retrospective cohort study. Gastric impactions were defined as feed extending to the margo plicatus after ≥24 h...
Tessler J.The fluorescent antibody reaction was studied in tissues of ponies infected with African horsesickness virus (AHSV). Lung, spleen, lymph node, liver, skeletal muscle, intestine, stomach, nerve ganglion and kidney were sectioned and stained by the direct fluorescent antibody technique (FA). Fluorescence was demonstrated only in the spleen and could be inhibited by using unconjugated antiserum.
Welles EG, Prasse KW, Moore JN.Protein C content and plasminogen activity were measured in plasma from 100 horses with signs of colic. Data were analyzed by grouping horses 4 ways. Each horse was allotted to 1 of 2 outcome groups (survivors and nonsurvivors), 1 of 3 broad-category diagnosis groups (inflammatory disorders, strangulating obstructions, and all other gastrointestinal disorders), and 1 of 2 clinical management groups (medical and surgical). In a fourth grouping, all horses (although numbers of horses included in each subgroup were small) were assigned either to specific diagnostic groups that had high expectatio...
Simmons TR, Gaughan EM, Ducharme NG, Dill SG, King JM, Anderson WI.Excessive administration of phenylbutazone was associated with development of right dorsal ulcerative colitis. The clinical signs of right dorsal colitis include chronic colic and weight loss. The laboratory abnormalities include panhypoproteinemia and a high WBC count in the abdominal fluid. Medical management of the chronic colic and protein-losing enteropathy associated with the ulcerative lesions in the right dorsal colon and surgical bypass of the right dorsal colon did not result in long-term resolution of clinical signs. Resection of the ulcerated right dorsal colon through a right late...
Merritt AM, Kohn CW, Ramberg CF, Cimprich RE, Reid CF, Bolton JR.Five clinically normal, mature horses and 11 with chronic diarrhea were given 51Cr-tagged Cohn fraction V equine albumin intravenously. All urine and feces were collected separately, and blood for plasma analysis was taken periodically for 5 to 8 days after injection of the isotope. Plasma clearance of albumin into the intestinal tract of normal horses was calculated as 0.67 +/- 0.23 (SD) ml/kg of body weight/day, with 1.33 +/- 0.69% of the 51Cr dose appearing in the feces in 5 days. Of the 11 diarrheal horses, 8 had a plasma clearance of 0.49 +/- 0.21 ml/kg/day with 1.12 +/- 0.68% of the dose...
Traub-Dargatz JL, Schultheiss PC, Kiper ML, Stashak TS, Wrigley R, Schlipf J, Applehans FM.Fibrosis of the small intestine led to recurrent colic and weight loss in 2 ponies and 5 horses. There was a reduction in the length of the small intestine to one-half normal in horses 4 to 7. Histologic examination revealed substantial small intestinal submucosal fibrosis and arteriole sclerosis. The cause was not determined, but an environmental factor was suspected because 3 horses were from the same farm and the other animals were from within a 10-mile radius of the farm. The submucosal fibrosis appeared to be secondary to sclerosis of arterioles in the submucosa and mesentery, with low bl...
Kobluk CN, Smith DF.An intramural hematoma involving a 40-cm segment of the distal portion of the jejunum caused intestinal obstruction and colic in a mature mare. The involved intestine was resected, and an end-to-end anastomosis was performed. The mare recovered completely, but 4 years later had colic caused by incarceration and volvulus of the distal portion of the jejunum, involving fibrous abdominal adhesions. The cause of hematoma was not identified; however, rupture of an intramural vessel after migration of Strongylus vulgaris larvae was considered a possibility because of the histologic observation of an...
Green P, Tong JM.Although wood chewing by horses is recognised as a common vice, there are few reports of specific disease associated with the habit. Two cases of acute obstruction of the small intestine by solid aggregations of wood splinters are described in horses which were both habitual wood chewers. Details are presented of the clinical findings in these cases, including the surgical treatment of acute colic. Both horses returned to full working fitness. The authors review the syndrome of enterolithiasis in horses, and discuss the causes and significance of wood chewing as a stable vice.
Henninger RW, Horst J.Magnesium sulfate, a saline laxative, is often used for treatment of intestinal impactions in horses. Clinical signs of hypermagnesemia are an uncommon complication following oral administration of magnesium sulfate. Overdose of magnesium sulfate in combination with renal insufficiency, hypocalcemia, or compromise of intestinal integrity may predispose horses to magnesium toxicosis. Establishment of diuresis with fluids and IV administration of calcium may provide successful treatment of magnesium toxicosis in horses.
Cuevas-Ramos G, Domenech L, Prades M.Postoperative reflux (POR) is a well-recognized complication after colic surgery in horses, particularly when presenting small intestinal pathology. Even though much has been written about the pathophysiology and management of POR, additional clinical studies are needed to better understand and anticipate this complication. The aim of the study was to provide clinical evidence of ultrasound findings in the postoperative period (three days). The study is based on transcutaneous abdominal ultrasounds of the caudoventral abdomen during the postoperative period (three days), in 58 horses, presente...
Ward AC, Sriranganathan N, Evermann JF, Traub-Dargatz JL.Escherichia coli was isolated from the feces and intestines of foals with and without diarrhea. Piliation of isolates was demonstrated by electron microscopy and agglutination in antisera having specificity for K88, K99, P987 and F41 pili. Piliation was also demonstrated by electron microscopy on organisms which did not react with any of the antisera.
Megid Gomaa NA, Köller G, Fritz Schusser G.To measure serum alcohol dehydrogenase (ADH) activity in horses with acute intestinal obstruction and to determine the diagnostic and prognostic utility of this analyte. Methods: Prospective observational study. Methods: University Veterinary Hospital. Methods: Thirty healthy horses (control group) and 77 horses with acute intestinal obstruction, including 36 horses with nonstrangulating obstruction (23 with left ventral colon impaction and 13 with left dorsal displacement [G1], 22 with small intestinal strangulation [G2], and 19 with colon torsion [G3]). Methods: Serum ADH activity was assaye...
Wolter R, Nouwakpo F, Durix A.A complete pelleted diet (table 1) containing 11 p. 100 of crude protein and 17 p. 100 of cellulose (ADF-lignine according to the method of Van Soest) was distributed to ponies and rabbits. Total digestibilities, partial cumulative digestibilities in different compartments of the digestive tract (stomach, small intestine, caecum, proximal and distal colon) and changes in biochemical composition, measured by pH, VFA, lactic acid and ammonia concentrations, were compared. Total digestibilities (table 2). There was no significant difference in dry matter between the two species. Crude protein dig...
Gandini M, Giusto G.7 horses (3 geldings, 2 mares, and 2 stallions) were examined because of acute colic caused by small intestinal obstruction involving the aborad portion of the jejunum and orad portion of the ileum. All horses underwent a routine colic examination on arrival and had a diagnosis of strangulating obstruction of the small intestine. All horses underwent emergency exploratory laparotomy, in which the affected aborad portion of the jejunum and orad portion of the ileum were resected; in 5 horses, a hand-sewn end-to-end jejuno-ileal anastomosis was combined with a hand-sewn incomplete ileocecal bypa...
Patterson-Kane JC, Sanchez LC, MacKay RJ, Sundberg JP, Homer BL.A 4-year-old Quarter Horse gelding was presented with a history of weight loss of 6 months duration, along with extensive ventral subcutaneous edema. Clinicopathologic findings included a markedly low serum total protein (2.9 g/dl) and a low packed cell volume (24%). The mucosal surface of the distal jejunum and entire ileum were carpeted with numerous polypoid, papillary, and glandular masses comprised of pseudostratified tall columnar cells and large numbers of interspersed goblet cells. Neoplastic change was diffuse throughout the mucosa of each mass, but abrupt demarcation occurred between...
Beder NA, Mourad AA, Aly MA.As means for enhancing gastrointestinal (GI) motility, prokinetics have previously been evaluated in different breeds of horses with varying success. No previous studies were conducted to evaluate the effect of prokinetics on the intestinal tract of Arabian horses breed. Using B-mode ultrasound in the quantification of intestinal contractility, this study aimed to compare the impact of neostigmine and metoclopramide on the intestinal motility of healthy Arabian horses. Methods: Twenty-one clinically healthy Arabian horses were equally distributed into three groups. The control group was admini...
Norman T, Chaffin K, Schmitz D.The equine small intestine is challenging to evaluate ultrasonographically. In humans, hydrosonography has been used to improve ultrasonographic images of the small intestine. We hypothesized that fasting horses for 24 h would enhance the ability to image the small intestine transabdominally by separating intestinal loops and reducing intraluminal gas, and that the administration of intragastric contrast agent would further improve that ability. Ten healthy horses were examined ultrasonographically under three treatment conditions: (a) regular diet, (b) after a 24-h fast, and (c) fasted plus i...
Johnston JK, Freeman DE, Gillette D, Soma LR.Sheets of mucosa from the jejunum of healthy horses were mounted in incubation chambers and bathed with Krebs-Ringer bicarbonate solution. Changes in tissue function and histologic appearance were compared after the following conditions: (1) control conditions for 30 minutes with 95% O2/5% CO2 in the gas phase; (2) same conditions as control, except incubation with superoxide dismutase (300 U/ml) during the last 18 minutes; (3) anoxia for 15 minutes with 95% N2/5% CO2, followed by reoxygenation for 15 minutes; (4) same conditions as 3, except incubation with superoxide dismutase during reoxyge...
Stick JA, Loeffler BS, Arden WA, Chou CC.The effects of butorphanol tartrate on arterial pressure, jejunal blood flow, vascular resistance, oxygen extraction, and oxygen uptake were determined in 10 anesthetized ponies ventilated with a mixture of halothane and 100% oxygen, using isolated autoperfused jejunal segments. Physiologic saline solution or butorphanol tartrate (0.2 mg/kg of body weight) was administered as a single bolus into the left jugular vein. By 2 minutes, butorphanol decreased arterial blood pressure and intestinal blood flow, and increased intestinal oxygen extraction. However, intestinal vascular resistance and oxy...
Dierckins MS, Sherman DM, Gendron-Fitzpatrick A.A presumptive diagnosis of paratuberculosis was made in a Sicilian ass on the basis of a history of chronic diarrhea and weight loss, pasture exposure to a heifer with paratuberculosis confirmed by bacterial culture of feces, postmortem identification of granulomatous inflammation of the intestine containing acid-fast organisms, the absence of acid-fast organisms in extraenteric tissues, and the absence of exposure to tuberculosis. The literature on paratuberculosis in equids is reviewed. The potential for cross-species transmission is emphasized. Justification for consideration of Mycobacteri...
Orsini JA, Orsini PG, Sepesy L, Acland H, Gillette D.Intestinal carcinoid, or argentaffinoma, should be an etiologic consideration for horses with chronic colic. A mare was referred with a history of chronic colic. Previously, the signs of colic had subsided in response to impiric treatment, but recent episodes of colic did not. Clinical signs and results of physical examination supported the finding of strangulating obstruction of the small intestine. Exploratory celiotomy revealed internal herniation with simultaneous volvulus of the jejunum and accompanying carcinoid.
Smith DF.The pathophysiology, diagnostic evaluation and medical management of the horse with intestinal obstruction is outlined. Emphasis is on early and accurate determination of the need for surgery and on providing optimal preoperative medical support.
