Use of a biodegradable self-expanding stent in the management of a benign oesophageal stricture in a cat

An 11-year-old domestic shorthair cat presented with a six-week history of regurgitation following a dental procedure. Endoscopy identified a single oesophageal stricture in the cervical oesophagus. Stricture reformation occurred following endoscopic balloon catheter dilation on two occasions. Following a third balloon dilation a biodegradable polydioxanone self-expanding stent was placed across the stricture site. Following the implantation the cat was able to eat soft canned food orally without regurgitation. Fluoroscopic examination performed four months after placement indicated that the stent was no longer present and the cervical oesophagus was able to pass boluses of canned food with no signs of obstruction.     

Infectious bovine keratoconjunctivitis and lymphofollicular hyperplasia of the third eyelid in heifers

On a dairy cattle farm, infectious bovine keratoconjunctivitis was diagnosed in 29 (24%) calves and heifers aged from 2 weeks to 1 year old. The highest infection rate (18%) occurred in animals aged 3-6 months. The bacteriological examination of swabs from the affected animals yielded several species of bacteria: Moraxella bovis, Neisseria ovis, N. cuniculi, plasma coagulase-negative Staphylococcus spp., alpha-haemolytic Streptococcus spp., Arcanobacterium pyogenes and Escherichia coli. Moraxella bovis and N. ovis were the most common isolates. Hyperplasia of the lymphatic tissue of the third eyelid in the form of nodules 7-8 mm in diameter was diagnosed in two heifers aged 8 and 10 months.     

SAFETY OF PERCUTANEOUS ULTRASOUND–GUIDED BIOPSY OF RENAL ALLOGRAFTS IN THE CYNOMOLGUS MONKEY: RESULTS OF 348 CONSECUTIVE BIOPSIES

The safety of a technique for ultrasound-guided biopsy of renal allografts was evaluated based on 348 consecutive procedures in cynomolgus monkeys. A spring-loaded biopsy device with an 18G tru-cut biopsy needle was used to biopsy renal allografts in 139 cynomolgus monkeys performed either on clinical indication (n = 95 animals) or as serial protocol biopsies (n = 44 animals) for a total of 348 biopsies. Monkeys having serial biopsies received between 3-9 biopsies per animal. All others received non-protocol biopsies that were performed on clinical indication, and the range was 1-15 biopsies per animal. No life-threatening complications or deaths occurred and there were no clinically detectable minor complications such as macrohematuria. Self-limiting complications such as small arteriovenous fistulas (n = 4, 3-5 mm large) were detected with Doppler ultrasound and resolved hemodynamically after 2-4 weeks. Three animals developed hematomas ranging 4 mm-2 cm in diameter and were no longer sonographically evident 2-4 weeks later. Ultrasound-guided biopsy of renal allografts can be performed with a high degree of safety in small (3-5 kg) laboratory animals such as the cynomolgus monkey and provides a valuable tool for renal transplantation research. Even when cores were taken at two week intervals no major complications occurred and only rarely were clinically irrelevant complications detected. Experience with diagnostic ultrasound, both gray scale and Doppler, is important for both safety and the recognition of complications that may arise.     

Balloon dilation for the treatment of chronic recurrent nasopharyngeal stenosis in a cat

Balloon dilation was used for the treatment of a recurrent nasopharyngeal stenosis in a cat with chronic stertorous breathing. The procedure was performed on three occasions at intervals of three and four months using a 15 mm valvuloplasty balloon dilation catheter. After the first dilation, clinical signs reappeared within two weeks due to re-stenosis. After the second dilation, all signs of nasopharyngeal disease disappeared, and did not recur. Endoscopic re-evaluation after four months revealed a markedly enlarged nasopharyngeal opening with some degree of stenosis, and a third balloon dilation was performed. Five months later, the cat remained without clinical signs, although some recurrence of the stenosis was visible endoscopically. Complications occurred after the first dilation, and included mild conchal necrosis and transient mucopurulent discharge. Balloon dilation is a minimally invasive technique and can be a successful procedure for treating nasopharyngeal stenosis in cats.     

Balloon Dilation of Congenital Subaortic Stenosis in the Dog

Balloon dilation during cardiac catheterization was evaluated for the treatment of congenital subaortic stenosis (SAS) in nine dogs. Under general anesthesia, bilateral cardiac catheterization was performed through the right jugular vein and carotid artery. Thermodilution cardiac output, and left ventricular and aortic root pressures and angiograms were obtained before and after balloon dilation. Balloons measuring 18–20 mm in diameter and 30–40 mm in length were positioned across the stenosis and three inflations 4–5 minutes apart were performed. There was no significant change in cardiac output, aortic pressure, or degree of aortic regurgitation after balloon dilation. For the entire group balloon dilation resulted in significant decreases in left ventricular systolic pressure (-61.2 ± 37.2 mm Hg [mean change ± SD], range -14 to -123), mean systolic pressure gradient (-39.6 ± 24.4 mm Hg, range –8.4 to -72.2), and peak systolic pressure gradient (-64.3 ± 46.5 mm Hg, range –17 to –143). Calculated left ventricular outflow cross-sectional area increased significantly (+.4 ± .5 cm², range –.06 to + 1.30). Clinical signs improved in the five symptomatic dogs. Individual hemodynamic responses varied widely, but the magnitude of improvement correlated with the severity of obstruction. Three dogs showed a decrease of 60% or greater (≥100 mm Hg), and six dogs showed a decrease of 25–50% (17–71 mm Hg) in peak systolic gradient after balloon dilation. Complications were frequent but most were transient and manageable. These preliminary results suggest that balloon dilation can acutely decrease outflow resistance in dogs with SAS and may be effective therapy for some affected dogs.     

Recurrent single oesophageal stricture treated with a self-expanding stent in a cat

A 1-year-old, female spayed domestic shorthair cat was presented with a 4-week history of dysphagia and regurgitation soon after oral treatment with clindamycin. Fluoroscopic and endoscopic examinations confirmed the presence of a single cervical oesophageal stricture 4 cm caudal to the pharynx. A fluoroscopically and endoscopically guided balloon dilation was performed six times consecutively over a period of 3 weeks as reformation of the stricture appeared within 3-7 days. Feeding via percutaneous endoscopic gastrostomy-tube as long-term management of the condition was declined by the owner. A self-expanding metal oesophageal stent with the following dimension was subsequently implanted: fully open diameter 16 mm, length 30 mm. After stent implantation, the cat was fed on mashed canned food and did not show any clinical signs for 12 months. Twelve months post-implantation the cat was no longer able to eat even liquid food, became lethargic and the owner opted for euthanasia. On post-mortem examination the stent surfaces were overgrown by oesophageal mucosa by approximately 50%. Stent obstruction was detected and caused by swallowed hair which also seemed to have hampered mucosal integration in the distal part of the stent.     

Aldosterone plasma concentration in horses with heart valve insufficiencies

In humans and small animals, heart disease can lead to an increase in aldosterone, and the aldosterone level correlates with the severity of the heart disease. In horses similar interactions may be possible and may lead to an increase in aldosterone in horses with heart valve insufficiencies. In a prospective clinical trial eight healthy horses (control group) and 40 horses with heart valve disease were examined. In all horses, a clinical (auscultation), electro- and echocardiographic examination was performed and aldosterone plasma concentration was determined. The median aldosterone plasma concentration in the control group was 23.95 pg/ml. Twenty-one out of 40 horses with heart valve insufficiencies and without dimensional changes by echocardiography (group 1) showed a median aldosterone plasma concentration of 45.5 pg/ml. Five out of the 40 horses had a left atrial (LA) dilation and an average LA size with 147.6+/-11 mm (group 2) and a median aldosterone plasma concentration of 95.9 pg/ml. Five other horses had a left ventricular (LV) dilation with an average LV size of 141.6+/-6.8 mm (group 3) and a median aldosterone plasma concentration of about 115.3 pg/ml. In this group a positive correlation between aldosterone plasma concentration and LV existed (r=0.9, P=0.03). Nine horses with both LA (152.8+/-11.4 mm) and LV dilatation (145+/-9 mm, group 4) had a median aldosterone plasma concentration of 161.2 pg/ml. Significant differences of the aldosterone concentrations were observed between the control group and the horses with LA and LV dilation (group 4, P=0.0005), as well as between group 1 (horses with heart valve insufficiency but without dilation) and group 4 (P=0.0006). The study confirms that, as reported for other species, aldosterone rises as the severity of valvular disease increases. However, in this study, as there is only significant difference from normal in the most affected group, it will require further study before the plasma aldosterone level can be relied on as an indicator of the severity of heart disease in an individual horse.     

ULTRASONOGRAPHIC OBSERVATION OF SECRETIN-INDUCED PANCREATIC DUCT DILATION IN HEALTHY CATS

Secretin is a polypeptide hormone that stimulates secretion of bicarbonate from the exocrine pancreas and, in healthy human subjects, causes transient pancreatic duct dilation observable sonographically. In humans with chronic pancreatitis, secretin administration fails to cause pancreatic duct dilation, theoretically due to the restrictive effects of periductal fibrosis. We characterized the effect of exogenous secretin administration on the width of the pancreatic duct in nine healthy domestic cats. Cats were given a commercially available secretin product (ChiRho Stim™) while the pancreatic duct was monitored sonographically. Mean pancreatic duct diameter increased from 0.77±0.33 to 1.42±0.40 mm after secretin administration ( P =0.0017). The mean percent increase in pancreatic duct diameter over basal diameter for all time points up to 15 min postsecretin administration was 101.9±58.8%. Applicability of this technique to diagnose chronic pancreatitis in cats will need to be investigated.     

Choledochal cyst with secondary cholangitis,choledochitis, duodenal papillitis,and pancreatitis in a young domestic shorthair cat

Choledochal cysts, congenital segmental dilations of the common bile duct, have been reported in few cats, and histologic characterization is lacking. A 20-mo-old spayed female domestic shorthair cat was presented because of vomiting and weight loss. There was progressive elevation of liver enzyme activity (ALT > ALP, GGT) and hyperbilirubinemia. Diagnostic imaging identified focal cystic dilation of the common bile duct, dilation and tortuosity of adjacent hepatic ducts, and a prominent duodenal papilla. A choledochal cyst was suspected, and the animal was euthanized. On postmortem examination, there was a 2-cm, firm, thickened, cystic dilation of the common bile duct, patent with adjacent ducts. Histologically, the cyst wall was expanded by fibroblasts, collagen, and lymphoplasmacytic inflammation. Adjacent bile ducts were markedly dilated and tortuous, with lymphoplasmacytic inflammation and papillary mucosal hyperplasia that extended to the major duodenal papilla. There was chronic neutrophilic cholangitis, suggesting bacterial infection and/or disturbed bile drainage, extrahepatic obstruction, and lymphoplasmacytic pancreatitis with ductular metaplasia. Prominent lymphoid follicles within biliary ducts and duodenum suggested chronic antigenic stimulation. Choledochal cysts can be associated with chronic neutrophilic cholangitis, extrahepatic obstruction, choledochitis, duodenal papillitis, and pancreatitis, and should be a differential for increased hepatic enzymes and hyperbilirubinemia in young cats.     

Intrapelvic Urethral Anastomosis A Comparison of Three Techniques

Three intrapelvic urethral anastomosis techniques were performed on 12 mature male dogs to compare the degree of stricture. The intrapelvic urethra was transected 1 cm caudal to the prostate, and anastomosis was performed using either suturing of the urethra over an indwelling catheter, suturing of the urethra without an indwelling catheter, or apposition of the urethra without sutures over an indwelling catheter. Postoperatively, the dogs were evaluated using clinical urination patterns, biochemical tests, radiography, and pathology. Three of four suture-catheter dogs and one of four catheter-only dogs had normal urinary patterns. Stricture (25-84%) with urethral dilation or fistulas tracts was visible on retrograde, positive contrast urethrograms of 3 of 12 intact dogs 20 weeks after surgery, and on all 12 excised lower urinary tracts. Suture-catheter dogs subjectively had the least amount of stricture. All eight dogs (1 suture-catheter dog, 4 suture-only dogs, and 3 catheter-only dogs) with severe stricture (greater than 60% lumen diameter reduction) had histopathologic signs of chronic, inflammatory urinary tract disease, including four with chronic, ascending lymphocytic pyelonephritis. Hydroureter and hydronephrosis developed in two catheter-only dogs. Complete urethral transection resulted in some degree of stricture, regardless of technique used for anastomosis. Urethral anastomosis over an indwelling catheter appeared to result in a lesser degree of stricture and clinical and histopathologic derangement.     

Pulmonic stenosis in dogs: balloon dilation improves clinical outcome

Medical records of 81 dogs with severe pulmonic stenosis from 2 referral centers were examined retrospectively. Forty dogs underwent balloon valvuloplasty (BV), which was performed by 1 operator, whereas 41 did not. The mean age at latest follow-up was 41.5 months. A statistical comparison of the clinical outcome and survival was performed. Dogs revealing clinical signs at presentation showed a 16-fold increase in risk of death compared with asymptomatic dogs (P < .001). Statistical analyses demonstrated that an increase of 1 mm Hg in transstenotic pressure gradient (PG) at presentation was associated with a 3% increase in hazard rate (P < .001). Thirty-seven dogs survived BV with a median reduction in PG of 46%. The median preoperative PG was 120 mm Hg, and median PG 24 hours postoperatively was 55 mm Hg with a median of 55 mm Hg 6 months post-BV. Twenty (49%) of the non-BV (NBV) dogs remained asymptomatic at last follow-up. Fourteen (34%) of the NBV dogs died or were euthanized because of heart disease related to pulmonic stenosis. Twelve of these dogs died suddenly, whereas only 1 of the BV dogs died suddenly. After adjusting for PG, clinical signs at presentation, and age, BV or dilation was associated with a 53% reduction in hazard rate (P = .005). This study indicates that BV, when performed by an experienced operator, appears to be successful both in alleviating clinical signs and in prolonging survival in dogs with severe pulmonic stenosis.     

Surgically induced tumor seeding in eight dogs and two cats

Surgically induced tumor seeding was diagnosed in 8 dogs and 2 cats. All animals had histologic confirmation of neoplasia in an unusual location or pattern, and a history of surgical manipulation of a similar histologic-type tumor at the site of seeding. Highly malignant carcinomas (8/10 animals) were the most common tumor type. Seeding occurred secondary to a variety of surgical procedures and in the face of various adjuvant therapies. Seeded tumors were recognized from 2 to 30 weeks after the causal procedure (median, 6 weeks). Survival times after the causal procedure ranged from 15 to 131 weeks (median, 45 weeks) and 8 of 10 animals died or were euthanatized because of seeded tumors.     

Efficacy of tropicamide,homatropine, cyclopentolate,atropine and hyoscine as mydriatics in Angora goats

Abstract

AIM: To document the efficacy of five commercially available mydriatics for their potential for diagnostic and therapeutic use in Angora goats.

METHODS: Over 8 weeks, the mydriatic effects of 1% tropicamide, 2% homatropine, 1% cyclopentolate, 1% atropine and 0.25% hyoscine were evaluated. Given as block treatments, drugs were applied randomly to one eye of 10 Angora goats, and the contralateral eye served as a control. Vertical and horizontal pupil diameters were measured to document onset ofeffect, time to reach a difference of 5 mm in the vertical/horizontal pupil diameter between eyes, time to maximum pupillary dilation, and duration of mydriatic action.

RESULTS: Onset of mydriasis for all drugs occurred within 15 minutes. Time to reach a difference of 5 mm in the vertical pupil diameter between eyes was shortest for 1% tropicamide and 0.25% hyoscine (0.5 h), then 2% homatropine and 1% atropine (0.75 h), and longest for 1% cyclopentolate (1.5 h). The maximum vertical pupillary dilation occurred earliest with 1% tropicamide and 1% atropine (2 h), followed by 0.25% hyoscine (3 h), 2% homatropine (4 h), and latest with 1% cyclopentolate (8 h). The duration of vertical dilation of the pupil was shortest with 1% tropicamide (6 h), then 2% homatropine (12 h), 1% cyclopentolate (12 h), 1% atropine (24 h), and longest for 0.25% hyoscine (96 h).

The time to reach maximum horizontal dilation of the pupil in treated eyes was shortest with 1% cyclopentolate (1 h), followed by 1% tropicamide (1.5 h), 0.25% hyoscine (3 h), 2% homatropine (3.5 h), and 1% atropine (4 h). The duration of horizontal pupil dilation was shortest with 1% tropicamide (4.5 h), and longest with 0.25% hyoscine (48 h).

CONCLUSION: All five mydriatics induced clinical dilation. Tropicamide (1%) had the shortest duration of effect, but gave incomplete dilation. Good dilation was achieved with 1% cyclopentolate and 2% homatropine, but took too long to reach maximum dilation for routine mydriasis. The largest vertical dilation of the pupil was achieved with 1% atropine and 0.25% hyoscine, but pupils remained dilated for more than 24 h.

CLINICAL RELEVANCE: For routine mydriasis in goats, it is recommended that 1% tropicamide be used, though there may be incomplete dilation. For a longer duration of mydriasis, such as in the treatment of anterior uveitis, 1% atropine or 0.25% hyoscine would be the drugs of choice.     

ULTRASONOGRAPHIC INTESTINAL HYPERECHOIC MUCOSAL STRIATIONS IN DOGS ARE ASSOCIATED WITH LACTEAL DILATION

In this retrospective study, the medical records of 23 dogs with the sonographic feature of small intestinal hyperechoic mucosal striations and an endoscopic or surgical intestinal biopsy were reviewed. Histopathologic lacteal dilation was present in 96% of dogs with mucosal striations. Sonographic findings associated with mucosal striations included: mild jejunal wall thickening (96%), mild duodenal wall thickening (78%), mucosal speckles (70%), and abdominal effusion (87%). The mucosal striations were diffuse (70%) or multifocal (30%) and did not cause loss of wall layering, except in one dog with a severe mural lipogranuloma. Mesenteric lymphadenopathy was identified in 9% of dogs. Thirteen dogs with endoscopic biopsies had mild to moderate villus lacteal dilation and the nine dogs with surgical biopsies had moderate to severe dilation. Inflammatory infiltrates were mild (61%) or moderate (30%) with variable numbers and combinations of cells, including eosinophils (65%), plasma cells (61%), lymphocytes (57%), and neutrophils (30%); one dog had disseminated villus histiocytic sarcoma. The biochemistry changes and clinical signs were consistent with protein-losing enteropathy in 78% of dogs. Hyperechoic mucosal striations in dogs are associated with lacteal dilation and are frequently associated with mucosal inflammation and protein losing enteropathy.     

Ultrasonographic and histopathological features in 8 cats with fibrotic small intestinal stricture

Benign stricture is an uncommon cause of chronic small intestinal obstruction in the cat. The purpose of this retrospective case series was to describe the ultrasonographic features, histopathological findings, and clinical presentation in a group of cats with benign small intestinal stricture. Inclusion criteria were cats presenting during the period 2010‐2017, and that had ultrasonography and small intestinal stricture confirmed at surgery. For each cat, clinical data and ultrasonographic findings were retrieved from the medical record, and histopathology, where available, was reviewed. Eight cats met the inclusion criteria. The location of strictures was duodenum (1/8), mid‐ to distal jejunum (4/8), and ileum (3/8). Ultrasonographic findings included gastric distension (8/8) and generalized (3/8) or segmental (5/8) intestinal dilation consistent with mechanical obstruction. Ingesta did not propagate beyond the strictured segment. Wall thickening was mild to moderate (3‐6 mm). Normal wall layering was disrupted in all cats. Strictures were predominantly hypoechoic (7/8) and associated with hyperechoic peri‐intestinal mesentery (6/8). Annular strictures (5/8) were less than 15 mm in length whereas long‐segment strictures (3/8) were greater than 15 mm in length. Histopathology showed transmural disease with fibrosis and inflammation (8/8), often (6/8) extending into the bordering mesentery. The mucosa was the most severely affected layer and epithelial injury accompanied the mucosal fibrosis/inflammation. Clinical presentation reflected delayed diagnosis of chronic bowel obstruction with debilitation (8/8), marked weight loss (8/8), and prerenal azotemia (5/8). Benign fibrostenotic stricture should be considered a differential diagnosis in debilitated young cats presenting with chronic bowel disease and ultrasonographic features of intestinal obstruction.     

Galenia africana L. poisoning in sheep and goats: hepatic and cardiac changes.

Lesions in 4 field cases (3 sheep and 1 goat) of 'waterpens' or water belly, caused by the plant Galenia africana, are described. The clinical pathological and pathological findings in 7 sheep which were drenched with toxic plant material are also reported. Inappetence, ruminal stasis and apathy as well as tachycardia were noticed in some of the sheep towards the end of the dosing period. The most prominent clinical pathological change in the experimental animals was an increase in the activity of gamma-glutamyltransferase which in some animals occurred within days after commencement of dosing. This indicates liver involvement in the early stages of the intoxication, and at this stage no heart abnormalities were detected clinically, clinical pathologically or with cardiac function tests. Decrease in cardiac function were recorded in 2 sheep towards the end of the dosing period. Liver and heart lesions were present in all the animals. In some cases hepatic changes were mild and characterized by dilation of central veins and sinusoids and, less commonly, centrilobular fibrosis. More advanced lesions included centrilobular fibrosis and bridging between neighbouring lobules with adjacent areas of coagulative necrosis, lysis and ballooning degeneration of hepatocytes. Myocardial changes occurred in the free ventricular walls and interventricular septum and comprised hypertrophy of myocytes with consequent degeneration and necrosis and fibrosis. In cases of longer duration myocytes were diffusely atrophic with scattered groups of remaining hypertrophic fibres. The clinical pathological and pathological features suggest that G. africana is primarily hepatotoxic with myocardial involvement occurring only in the terminal stages of the intoxication.     

Transendoscopic biopsy of the horse's airway mucosa

Transtracheal wash and bronchoalveolar lavage are diagnostic techniques that have been adopted from human medicine for monitoring inflammatory changes in the airway of the horse. Transendoscopic biopsy has also proven to be a valuable tool for obtaining samples of the airway mucosa in human patients. A transendoscopic technique was developed in this study for obtaining a respiratory mucosal biopsy from standing, sedated horses. Six normal adult horses were sampled at eight-week intervals for a total of three sample periods. Horses were monitored for adverse effects of the technique and none were noted. Sample sites were completely healed after eight weeks with no gross or histologic abnormalities. Biopsy samples were 3 to 4 millimeters in diameter, and 17 of 18 samples provided interpretable histological sections. Methods for handling, staining and evaluating tissue were also developed. The results of this study demonstrated that airway mucosal biopsy is a safe, repeatable technique that can be performed in the sedated, standing horse.     

Management of advanced tracheal collapse in dogs using intraluminal self-expanding biliary wallstents

Twenty-four client-owned dogs with tracheal collapse refractory to conventional treatment underwent management with an intraluminal self-expanding stainless-steel endoprosthesis (Wallstent). Initial improvement of clinical signs was observed in 95.8% of the dogs. Two dogs (8.3%) died within a median interval of 6 days after stent implantation due to incorrect placement and size of the stent and emphysema, respectively. A dry cough occurred temporarily in most of the patients. One dog each (4.1%) suffered mild transient tracheal hemorrhage and pneumomediastinum. The results showed that the initial survival rate of intraluminal stabilization was comparable with surgical implantation of extratracheal prostheses. Clinical reevaluation was performed in 18 dogs within a median interval of 68 days after treatment. Of the dogs treated, 30.4% were reported to be asymptomatic after stent implantation, 60.9% improved markedly, and 4.3% remained symptomatic. In all patients undergoing endoscopy, the Wallstents were almost completely covered with tracheal epithelium. A median shortening of 27.3% of the endoprosthesis within a median interval of 175 days after stent implantation in 15 of 18 dogs was noted. The shortening was associated with clinical signs in 2 patients. In 5 dogs, steroid-responsive granuloma formation resulted in a severe reduction of the tracheal lumen in 3 patients. The results suggest that implantation of Wallstents was minimally invasive and provided stabilization of collapsed thoracic tracheal portions in addition to the cervical part of the trachea. This minimally invasive method for the management of severe tracheal collapse therefore provides an attractive alternative to surgery.     

Treatment of atresia ani type I by balloon dilatation in 5 kittens and one puppy

Atresia ani is the most common anorectal anomaly in small animals. In the present study, an anal stricture (atresia ani type I) in five 3 to 8 weeks old kittens and one 4 month old puppy was treated by balloon dilation. In 4 kittens and the puppy the stricture was eliminated permanently and without complications by a single intervention. Only the smallest kitten with the most severe stenosis developed a rectal fistula as a complication of repeated balloon dilation, which necessitated surgical correction. Balloon dilation proved to be an efficient therapeutic method for anal atresia type I, and can be recommended as the treatment of choice.     

Use of a hyaluronate membrane for jejunal anastomosis in horses

OBJECTIVE: To compare the outcomes of double-layer inverting anastomosis (DIA), single-layer anastomosis (SLA), and single-layer anastomosis combined with a hyaluronate membrane (SLA+HA-membrane) with respect to stomal diameter, adhesion formation, surgery time, and anastomotic healing in horses. ANIMALS: 18 adult horses. PROCEDURE: Midline celiotomy and end-to-end anastomoses were performed. In control horses (n = 6), DIA was performed; in treated horses, SLA was performed (6) or SLA+HA-membrane was performed (6). Horses were euthanatized 21 days after surgery. Abdominal adhesions were evaluated grossly and histologically. Stomal diameters were measured ultrasonographically and compared with adjacent luminal diameters. Anastomotic healing was evaluated histologically for fibrosis and inflammation, tissue alignment, and inversion. Surgery times were recorded for the anastomotic procedure and compared among groups. RESULTS: There were significantly more adhesions in the SLA group, compared with the DIA and SLA+HA-membrane groups. Reduction in stomal diameters in the DIA group was significantly greater than the SLA and SLA+HA-membrane groups. Surgery times for the DIA group were significantly greater than the SLA and SLA+HA-membrane groups. Histologic findings of fibrosis, inflammation, and mucosal healing were similar among groups. There was significant tissue inversion in the DIA group, compared with the 2 treatment groups. Tissue alignment was not different among groups. CONCLUSIONS AND CLINICAL RELEVANCE: Use of a SLA+HA-membrane was an effective small intestinal anastomotic technique. This technique was faster to perform and resulted in a larger stomal diameter, compared with the DIA technique and significantly fewer perianastomotic adhesions, compared with the SLA technique.