Equine Choke: Emergency Assessment and Aftercare

This article provides veterinarians, veterinary technicians, and horse owners with a step-by-step emergency protocol for managing esophageal obstruction (choke) in horses. The guidance covers immediate assessment, sedation protocols, nasogastric lavage technique, and post-obstruction dietary management to prevent recurrence. All recommendations are based on published veterinary evidence and established clinical practice.

At a Glance

Emergency Recognition and Initial Assessment

Clinical Signs of Esophageal Obstruction

The horse with choke typically presents with a characteristic set of signs that owners and veterinarians should recognize promptly. The most common observation is the discharge of saliva and feed material from both nostrils, often accompanied by repeated swallowing attempts, extension of the head and neck, and coughing. The horse may appear anxious, paw the ground, or show signs of mild colic. In some cases, a visible or palpable swelling may be present along the left side of the neck at the site of obstruction.

The Merck Veterinary Manual describes choke as a condition where the esophagus becomes obstructed, most commonly by feed material such as hay, grain, or beet pulp. The obstruction can be partial or complete, and the severity of clinical signs correlates with the degree of obstruction and the duration before intervention.

Differentiating Choke from Other Conditions

Choke must be distinguished from other conditions that cause similar signs. Respiratory obstruction, such as from a foreign body in the trachea or severe laryngeal edema, produces inspiratory stridor and cyanosis instead of nasal discharge of feed. Colic may cause pawing and rolling but typically lacks the nasal discharge and swallowing attempts. Guttural pouch empyema or mycosis can cause nasal discharge but is usually accompanied by other signs such as head shaking or dysphagia.

The horse with choke will often continue to attempt to swallow, and the nasal discharge will contain recognizable feed material. If the obstruction is in the cervical esophagus, a firm swelling may be palpable. Thoracic esophageal obstructions are not palpable externally but may be suspected based on the horse's posture and repeated swallowing.

Immediate First Response for Owners

Owners who suspect choke should remove all feed and water immediately. The horse should be kept calm and quiet in a stall or small paddock. Do not attempt to force the horse to drink or eat, as this can worsen the obstruction or cause aspiration. Do not attempt to pass a tube or administer any oral medications.

The owner should contact a veterinarian immediately. While waiting, the horse's head should be kept low to reduce the risk of aspiration of saliva and feed material. If the horse is in a group, separate it from other horses to prevent competition or stress.

Sedation Protocols for Esophageal Relaxation

Rationale for Sedation

Sedation is a critical first step in managing equine choke. An alpha-2 agonist such as detomidine or xylazine provides sedation, muscle relaxation, and mild analgesia. The drug lowers the horse's head, which helps drain saliva and feed material from the pharynx and reduces the risk of aspiration. It also relaxes the esophageal musculature, which may allow the obstruction to pass spontaneously in some cases.

The American College of Veterinary Internal Medicine (ACVIM) recognizes sedation as a standard component of choke management. Sedation should be administered before any attempt at nasogastric intubation or lavage.

Drug Selection and Administration

Detomidine (0.01 to 0.02 mg/kg IV or IM) or xylazine (0.5 to 1.0 mg/kg IV or IM) are commonly used. The dose should be adjusted based on the horse's size, temperament, and degree of distress. Butorphanol (0.01 to 0.02 mg/kg IV) may be added for additional sedation and analgesia, particularly if the horse is painful or fractious.

The veterinarian should administer sedation intravenously when possible for rapid onset. If IV access is not available, intramuscular administration is acceptable but has a slower onset. The horse should be monitored for signs of excessive sedation, including ataxia, bradycardia, or respiratory depression.

Monitoring During Sedation

After sedation, the horse should be observed for 5 to 10 minutes. The head will typically lower, and the horse may become drowsy. Salivation may increase, and the horse may swallow more frequently. If the obstruction is partial, the horse may pass the obstruction spontaneously during this period.

If the obstruction does not resolve within 10 to 15 minutes of sedation, nasogastric lavage should be performed. The veterinarian should have all equipment ready before sedation to minimize delay.

Nasogastric Lavage Technique

Equipment Preparation

The following equipment should be assembled before beginning the procedure:

• Nasogastric tube (12 to 14 mm diameter for adult horses, smaller for foals)
• Lubricant (water-soluble or obstetrical lubricant)
• Bucket of warm water (body temperature, approximately 37 degrees Celsius)
• Pump or funnel for lavage
• Headlamp or good lighting
• Mouth speculum (optional, for safety)
• Sedation and emergency drugs

The tube should be measured from the nostril to the 13th to 15th intercostal space to estimate the distance to the stomach. A mark should be placed on the tube at this distance.

Passing the Nasogastric Tube

The horse should be adequately sedated and standing in a stable position. The tube is lubricated and passed gently through the ventral meatus of the nostril. The tube should be directed medially and ventrally as it enters the pharynx. The horse may swallow as the tube reaches the pharynx, which facilitates passage into the esophagus.

The tube should never be forced. If resistance is met, the tube should be withdrawn slightly and redirected. The tube should be advanced slowly, and the veterinarian should feel for the characteristic click as the tube passes through the thoracic inlet. The tube should be advanced to the premeasured mark.

Confirming Correct Placement

Correct placement in the esophagus must be confirmed before any lavage is performed. The following signs indicate esophageal placement:

• The tube passes easily with minimal resistance
• The horse may swallow or show mild discomfort
• Air can be heard moving through the tube when the free end is placed near the ear
• No respiratory effort is detected when the tube is open to the atmosphere

If the tube is in the trachea, the horse will cough violently, and air will move in and out of the tube with respiration. The tube should be withdrawn immediately if tracheal placement is suspected.

Lavage Procedure

Once the tube is confirmed in the esophagus, warm water is introduced through the tube using a pump or funnel. The water should be at body temperature to avoid causing esophageal spasm. Gentle pressure is applied, and the water is allowed to flow in and then drain back out. The process is repeated until the obstruction is cleared.

The water should be allowed to drain freely. If the water does not return, the tube may be blocked or the obstruction may be complete. The tube should be withdrawn slightly and repositioned. Never apply excessive pressure, as this can cause esophageal rupture.

The lavage fluid should be examined for feed material. As the obstruction clears, the fluid will become less cloudy and contain less feed. The procedure should be continued until the fluid returns clear and the horse can swallow normally.

Post-Lavage Assessment

After the obstruction is cleared, the tube should be removed slowly. The horse should be observed for signs of esophageal discomfort, such as repeated swallowing or extension of the neck. The horse should be offered a small amount of water to confirm that swallowing is normal.

If the obstruction cannot be cleared after 30 minutes of lavage, or if the horse shows signs of severe distress, the veterinarian should consider alternative approaches such as endoscopic removal or referral to a surgical facility.

Post-Obstruction Dietary Management

Immediate Dietary Restrictions

After the obstruction is cleared, the esophagus may be inflamed and edematous. The horse should not be offered any feed or water for 1 to 2 hours to allow the esophagus to rest. During this time, the horse should be monitored for signs of recurrence or aspiration.

After the rest period, the horse should be offered small amounts of water. If the horse drinks without difficulty, a soft mash can be offered. The mash should be made from soaked hay cubes or grass pellets, mixed with enough water to form a slurry. The mash should be offered in small amounts (1 to 2 quarts) every 2 to 3 hours for the first 24 hours.

Gradual Reintroduction of Feed

Over the next 2 to 3 days, the horse can be gradually transitioned to a more normal diet. The following schedule is a general guide:

• Day 1: Soaked hay cubes or grass mash only, offered 4 to 6 times per day
• Day 2: Add small amounts of soaked hay (soaked for 30 minutes in warm water) to the mash
• Day 3: Offer dry hay in small amounts, continue mash for one more day
• Day 4: Gradually reintroduce concentrates if needed, but continue to soak or moisten

The horse should be monitored closely during this transition. Any signs of difficulty swallowing, coughing, or nasal discharge should prompt a return to the soft diet and veterinary consultation.

Long-Term Feeding Modifications

Horses that have experienced choke may be at increased risk for recurrence, particularly if there is underlying esophageal pathology. Long-term feeding modifications can reduce this risk:

• Feed from slow-feeders or large-mesh hay nets to reduce intake rate
• Avoid feeding from the ground, which can increase the risk of aspiration
• Separate horses at feed time to prevent competition
• Soak beet pulp or other rapidly expanding feeds before feeding
• Avoid feeding large amounts of grain or pelleted feeds

The effect of feeder style on intake rate of equine concentrates has been studied, with evidence that slow-feeders can reduce the rate of feed consumption. This may be particularly beneficial for horses prone to choke.

Monitoring for Complications

Aspiration Pneumonia

Aspiration pneumonia is the most common and serious complication of equine choke. Feed material and saliva can enter the trachea and lungs during the obstruction or during lavage. Signs of aspiration pneumonia include fever, increased respiratory rate, nasal discharge (which may be purulent or bloody), coughing, and lethargy.

The horse should be monitored for these signs for at least 48 hours after the obstruction. Temperature should be taken every 6 hours. Any elevation above 38.5 degrees Celsius (101.3 degrees Fahrenheit) should be investigated. If aspiration pneumonia is suspected, the veterinarian should perform a thorough respiratory examination, including auscultation of the lungs, and may recommend diagnostic tests such as thoracic radiography or ultrasonography.

Esophageal Perforation

Esophageal perforation is a rare but life-threatening complication. It can occur from the obstruction itself, from the passage of the nasogastric tube, or from excessive pressure during lavage. Signs of perforation include subcutaneous emphysema (air under the skin of the neck), pain on palpation of the neck, fever, and signs of systemic inflammation.

If perforation is suspected, the horse should be referred immediately to a surgical facility. Treatment may include surgical repair, drainage, and intensive medical management.

Esophageal Stricture

Repeated episodes of choke or severe esophageal inflammation can lead to the formation of a stricture, or narrowing of the esophagus. This can cause chronic dysphagia and recurrent choke. Signs of stricture include difficulty swallowing, regurgitation of feed, and weight loss.

Diagnosis of stricture may require endoscopic examination or contrast radiography. Treatment options include dietary management, balloon dilation, or surgical resection in severe cases.

Megaesophagus

Megaesophagus is a condition characterized by dilation and poor motility of the esophagus. It can be a primary condition or secondary to chronic obstruction. A study published in Veterinary Pathology described megaesophagus in Friesian horses associated with muscular hypertrophy of the caudal esophagus. This condition may predispose horses to recurrent choke.

Horses with megaesophagus may require lifelong dietary management, including feeding from an elevated position and offering small, frequent meals.

Common Failure Patterns in Choke Management

Inadequate Sedation

One of the most common failures in choke management is inadequate sedation. Without sufficient sedation, the horse may resist passage of the nasogastric tube, and the esophageal musculature may remain contracted, preventing the obstruction from passing. The veterinarian should ensure that the horse is adequately sedated before attempting any intervention.

Excessive Force During Lavage

Applying excessive force during lavage can cause esophageal perforation or worsen the obstruction. The water should be introduced gently, and the tube should never be forced. If the water does not return, the tube should be repositioned instead of applying more pressure.

Premature Return to Normal Feed

Returning the horse to a normal diet too quickly can cause recurrence of choke. The esophagus needs time to heal, and the horse should be kept on a soft diet for at least 24 to 48 hours. The gradual reintroduction of feed should be monitored closely.

Failure to Monitor for Complications

Some horses may develop aspiration pneumonia or other complications days after the obstruction has been cleared. Failure to monitor the horse for these complications can lead to delayed treatment and worse outcomes. The horse should be monitored for at least 48 hours after the obstruction.

Records and Measurements

Documentation of the Episode

The veterinarian should document the following information for each choke episode:

• Date and time of onset
• Clinical signs observed
• Type of feed involved (if known)
• Duration of obstruction before intervention
• Sedation drugs and doses used
• Number of lavage attempts and volume of water used
• Time to resolution
• Post-obstruction diet and monitoring plan

This documentation can help identify patterns and risk factors for recurrence.

Monitoring Parameters

The following parameters should be recorded during the monitoring period:

• Temperature every 6 hours for 48 hours
• Respiratory rate every 6 hours for 48 hours
• Heart rate every 6 hours for 48 hours
• Appetite and water intake
• Frequency and character of bowel movements
• Any signs of coughing, nasal discharge, or difficulty swallowing

Follow-Up Examination

A follow-up examination should be performed 5 to 7 days after the obstruction. The veterinarian should assess the horse's overall condition, auscultate the lungs, and evaluate the esophagus for any signs of stricture or discomfort. If the horse has had multiple episodes of choke, further diagnostic testing may be warranted.

Welfare and Safety Context

Animal Welfare Implications

Choke is a painful and distressing condition for the horse. The obstruction causes discomfort, and the inability to swallow can lead to dehydration and malnutrition if prolonged. Prompt and effective management is essential to minimize suffering.

The World Organisation for Animal Health (WOAH) recognizes the importance of animal welfare in veterinary practice. Veterinarians have a responsibility to provide timely and appropriate care for horses with choke, including adequate sedation and pain management.

Safety Considerations for Handlers

Handling a horse with choke can be dangerous. The horse may be anxious, painful, and unpredictable. Sedation should be administered as soon as possible to calm the horse and reduce the risk of injury to handlers. The veterinarian should ensure that all personnel are positioned safely and that the horse is in a secure environment.

Regulatory Considerations

The use of sedatives and other drugs in horses must comply with local regulations, including withdrawal times for horses intended for slaughter. The veterinarian should be aware of the regulatory status of all drugs used and should advise the owner accordingly.

Decision Framework for Selecting Sedation and Lavage Approach Based on Obstruction Characteristics

Classification of Obstruction Type and Location

The management of equine choke requires a structured decision framework that accounts for obstruction characteristics, horse temperament, and available equipment. Obstructions are classified by location (cervical versus thoracic esophagus), completeness (partial versus complete), and composition (feed material, foreign body, or esophageal pathology). Each classification influences the sedation protocol, lavage technique, and escalation criteria.

Cervical obstructions are palpable or visible as a firm swelling along the left jugular groove. These obstructions are often accessible to direct manipulation and may respond more readily to sedation and lavage. Thoracic obstructions are not externally palpable and require careful tube passage to the level of the obstruction. The Merck Veterinary Manual notes that thoracic obstructions may be more challenging to clear and carry a higher risk of aspiration due to the proximity to the thoracic inlet.

Partial obstructions allow some passage of saliva and small amounts of water. The horse may show intermittent signs and may be able to swallow small volumes. Complete obstructions prevent any passage of material, leading to rapid accumulation of saliva and feed above the obstruction, increased distress, and higher risk of aspiration. The decision to proceed with lavage versus immediate referral depends on the completeness and duration of the obstruction.

Decision Algorithm for Sedation Protocol Selection

The choice of sedation protocol should be guided by the horse's cardiovascular status, temperament, and the anticipated difficulty of the procedure. The following algorithm provides a structured approach:

Step 1: Assess cardiovascular stability. Measure heart rate, pulse quality, mucous membrane color, and capillary refill time. Horses with tachycardia (heart rate greater than 60 beats per minute), weak pulses, or prolonged capillary refill time (greater than 3 seconds) may be dehydrated or in shock. These horses require cautious sedation with lower doses and intravenous fluid support before sedation.

Step 2: Evaluate temperament and pain level. Horses that are fractious, anxious, or showing signs of severe pain may benefit from the addition of butorphanol to the sedation protocol. The ACVIM recognizes that butorphanol provides additional sedation and visceral analgesia, which can facilitate tube passage and reduce the risk of injury to the horse and handlers.

Step 3: Select the primary sedative. For most adult horses, detomidine at 0.01 to 0.02 mg/kg intravenously provides reliable sedation with good esophageal relaxation. Xylazine at 0.5 to 1.0 mg/kg intravenously is an alternative with a shorter duration of action. For horses with bradycardia (heart rate less than 24 beats per minute), xylazine may be preferred due to its shorter duration of cardiac effects.

Step 4: Determine the need for additional agents. If the horse remains anxious after the initial sedative dose, a second dose of the same drug or the addition of butorphanol may be considered. The total dose should not exceed the labeled maximum for the drug.

Step 5: Allow time for drug effect. After sedation, allow 5 to 10 minutes for the drug to take full effect. During this time, observe the horse for head lowering, relaxation of the jaw, and decreased response to external stimuli. If the obstruction is partial, the horse may pass the obstruction spontaneously during this period.

Lavage Technique Selection Based on Obstruction Characteristics

The lavage technique should be adapted to the characteristics of the obstruction. The following table summarizes the approach for different obstruction types:

For soft feed material obstructions, warm water lavage with gentle pressure is typically effective. The water should be introduced slowly, allowed to soak the feed material for 30 to 60 seconds, and then drained. This cycle is repeated until the obstruction clears. The volume of water used per cycle should be 1 to 2 liters for adult horses, with careful monitoring of return flow.

For compacted grain or pellet obstructions, the feed material may form a dense plug that requires extended soaking. The initial lavage should use small volumes of water (500 ml to 1 liter) with longer soaking times (2 to 3 minutes) to allow the material to soften. Gentle pressure may be applied, but the tube should never be forced against resistance.

Beet pulp obstructions present a particular challenge because the material expands significantly when wet. The initial approach should use small volumes of water with careful monitoring of return flow. If the obstruction does not clear after several cycles, the veterinarian should consider endoscopic evaluation to assess the extent of the obstruction and the condition of the esophageal mucosa.

Escalation Criteria for Referral

The decision to refer a horse for advanced care should be based on specific criteria that indicate failure of initial management or the presence of complications. The following criteria warrant immediate referral to a surgical facility:

• Failure to clear the obstruction after 30 minutes of sedation and lavage
• Evidence of esophageal perforation (subcutaneous emphysema, pain on palpation, fever)
• Complete obstruction that prevents passage of any fluid
• Signs of severe respiratory distress or aspiration
• Recurrent obstruction within 24 hours of initial clearance
• Suspected foreign body or esophageal mass
• History of multiple choke episodes suggesting underlying pathology

The American College of Veterinary Internal Medicine recommends that horses with persistent obstruction or signs of complications be referred for endoscopic evaluation and possible surgical intervention. Endoscopy allows direct visualization of the obstruction, assessment of esophageal mucosal damage, and targeted removal of foreign bodies or feed material.

Troubleshooting Common Lavage Problems

Problem 1: Water does not return after lavage. This may indicate that the tube is blocked by feed material, the tube has passed beyond the obstruction into the stomach, or the obstruction is complete and prevents fluid passage. The tube should be withdrawn slightly and the position reassessed. If the tube is in the stomach, gastric fluid may be aspirated. If the tube is blocked, it should be removed, cleaned, and reinserted.

Problem 2: The horse coughs during tube passage. Coughing may indicate that the tube has entered the trachea or that fluid has entered the airway. The tube should be withdrawn immediately and the horse allowed to recover. If the horse shows signs of respiratory distress, oxygen should be administered if available. The tube should be reinserted only after the horse has stabilized.

Problem 3: The obstruction appears to move but does not clear. This may indicate that the obstruction is partially dislodged but remains lodged at a narrow point in the esophagus, such as the thoracic inlet or the cardia. The veterinarian should continue gentle lavage with the horse's head lowered to facilitate drainage. If the obstruction does not clear after several attempts, endoscopic evaluation may be necessary.

Problem 4: The horse becomes distressed during the procedure. Distress may indicate inadequate sedation, esophageal pain, or the development of complications. The procedure should be stopped, and the horse should be reassessed. Additional sedation may be administered, or the veterinarian may decide to refer the horse for advanced care.

Record System for Choke Episodes

A structured record system helps identify patterns, risk factors, and recurrence trends. The following template provides a framework for documenting each choke episode:

Episode Record Form

• Horse identification (name, age, breed, sex)
• Date and time of onset
• Clinical signs observed (nasal discharge, swallowing attempts, coughing, distress)
• Type of feed involved (hay, grain, beet pulp, pasture, other)
• Estimated duration of obstruction before intervention
• Sedation drugs and doses administered
• Number of lavage attempts
• Volume of water used per cycle
• Total lavage time
• Time to resolution
• Post-obstruction diet plan
• Monitoring parameters (temperature, respiratory rate, heart rate every 6 hours for 48 hours)
• Complications observed (aspiration pneumonia, esophageal perforation, recurrence)
• Follow-up examination findings (5 to 7 days post-obstruction)
• Recommendations for long-term management

This record should be maintained in the horse's medical file and reviewed before any subsequent choke episodes. Horses with multiple episodes should be evaluated for underlying esophageal pathology, including stricture, megaesophagus, or motility disorders.

Comparison of Sedation Protocols for Choke Management

The following comparison provides guidance on selecting the appropriate sedation protocol based on clinical circumstances:

The choice of protocol should be individualized based on the horse's condition and the veterinarian's experience. Horses with preexisting cardiovascular disease may require lower doses or alternative protocols.

Common Failure Patterns in Sedation and Lavage

Failure Pattern 1: Inadequate sedation leading to resistance. Horses that are not adequately sedated may resist tube passage, causing esophageal trauma or failure to clear the obstruction. The veterinarian should ensure that the horse is sufficiently sedated before attempting lavage. If the horse remains anxious after the initial dose, a second dose may be administered.

Failure Pattern 2: Excessive lavage pressure causing esophageal damage. Applying excessive pressure during lavage can cause esophageal perforation or worsen the obstruction. The water should be introduced gently, and the tube should never be forced. If the water does not return, the tube should be repositioned instead of applying more pressure.

Failure Pattern 3: Failure to recognize complete obstruction. Complete obstructions that prevent any fluid passage may require alternative approaches, such as endoscopic removal or surgical intervention. The veterinarian should recognize when lavage is not effective and escalate care appropriately.

Failure Pattern 4: Premature cessation of lavage. Some obstructions require multiple lavage cycles to clear completely. The veterinarian should continue lavage until the fluid returns clear and the horse can swallow normally. Premature cessation may leave residual feed material that can cause recurrence.

Welfare and Safety Context for Decision Making

The welfare of the horse should guide all decisions in choke management. The World Organisation for Animal Health (WOAH) emphasizes the importance of minimizing pain and distress in animals under veterinary care. Sedation and gentle lavage techniques reduce the stress and discomfort associated with choke management.

Handlers should be positioned safely during the procedure. The horse's head should be kept low to reduce the risk of aspiration, and all personnel should be aware of the horse's position and behavior. If the horse becomes distressed or aggressive, the procedure should be stopped and the horse reassessed.

The veterinarian should also consider the regulatory status of all drugs used, including withdrawal times for horses intended for slaughter. The owner should be advised of any withdrawal periods and the importance of compliance with local regulations.

Frequently Asked Questions

What is the difference between choke in horses and choke in humans?

In horses, choke refers to an esophageal obstruction, not a tracheal obstruction. The horse can still breathe, but cannot swallow. In humans, choke typically refers to a tracheal obstruction that prevents breathing. The two conditions are fundamentally different in their pathophysiology and management.

Can a horse die from choke?

Yes, choke can be fatal if not treated promptly. The most common cause of death is aspiration pneumonia, which occurs when feed material or saliva enters the lungs. Esophageal perforation is another rare but life-threatening complication. Prompt veterinary intervention significantly reduces the risk of death.

How long can a horse survive with choke?

The survival time depends on the severity of the obstruction and the development of complications. A horse with a partial obstruction may survive for several days, but dehydration and aspiration pneumonia can develop quickly. A horse with a complete obstruction should receive veterinary care within hours.

Can choke recur in the same horse?

Yes, horses that have experienced choke are at increased risk for recurrence. This may be due to esophageal inflammation, stricture formation, or underlying motility disorders. Long-term dietary management and monitoring are recommended for horses with a history of choke.

What should I do if my horse chokes while I am alone?

Remove all feed and water immediately. Keep the horse calm and quiet. Call your veterinarian and follow their instructions. Do not attempt to pass a tube or administer any oral medications. If the horse is in distress, try to keep its head low to reduce the risk of aspiration.

Is it safe to use a garden hose for lavage?

No, a garden hose should never be used for esophageal lavage. The pressure from a garden hose can cause esophageal perforation. Only a properly sized nasogastric tube with a pump or funnel should be used, and the water should be introduced gently.

Can choke be prevented?

Choke can be prevented in many cases by feeding management. Feed from slow-feeders or large-mesh hay nets to reduce intake rate. Soak beet pulp and other rapidly expanding feeds before feeding. Separate horses at feed time to prevent competition. Avoid feeding large amounts of grain or pelleted feeds.

When should I call a veterinarian for choke?

Call a veterinarian immediately if you suspect your horse has choke. Do not wait to see if the obstruction resolves on its own. Prompt veterinary intervention reduces the risk of complications and improves the outcome.

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References and Further Reading

• aaep.org
• www.merckvetmanual.com
• www.acvim.org
• Merck Veterinary Manual. Merck Veterinary Manual.
• Animal Health and Welfare. World Organisation for Animal Health.
• Megaesophagus in Friesian horses associated with muscular hypertrophy of the caudal esophagus.. Veterinary pathology, 2014.
• The effect of oxytocin on contractility of the equine oesophagus: a potential treatment for oesophageal obstruction.. Equine veterinary journal, 2000.
• Effect of feeder style on intake rate of equine concentrates.. Journal of equine veterinary science, 2026.
• Effects of airway obstruction on transmural pulmonary artery pressure in exercising horses.. American journal of veterinary research, 1997.
• Diagnosis of a sublaryngeal abscess in a Japanese Black calf using computed tomography.. The Journal of veterinary medical science, 2020.
• Ferrite sleeve as a choke for intracavitary microwave hyperthermia treatment using coaxial antennas. IEEE Transactions on Antennas and Propagation, 2022.
• A survey of the level of horse owner uptake of evidence-based anthelmintic treatment protocols for equine helminth control in the UK.. Veterinary parasitology, 2019.
• Trojan Horse nanotheranostics with dual transformability and multifunctionality for highly effective cancer treatment. Nature Communications, 2018.
• Primary esophageal obstruction in nursing foals - A retrospective analysis of 20 patients: Clinical presentation, disease course and complications. Pferdeheilkunde, 2018.
• Effect of grazing muzzles on the rate of pelleted feed intake in horses. Journal of Veterinary Behavior Clinical Applications and Research, 2016.
• Use of nasotracheal intubation during general anesthesia in two ponies with tracheal collapse. Frontiers in Veterinary Science, 2018.

This article is educational and is not a substitute for veterinary diagnosis or treatment. Contact a veterinarian for advice about an individual animal.