The horse's hindgut is enormous and performs many important functions. It is the place where fibre is fermented to provide energy for the horse. Ulcers in the hindgut can be extremely painful and also indicate that the 'fermenter' is not working properly - for this reason you should be familiar with the signs of hindgut ulcers.
Signs of Hindgut Ulcers in Horses
Unlike gastric ulcers, hindgut ulcers cannot be diagnosed with a gastroscope. While there are techniques like ultrasound & blood work to diagnose hindgut ulcers, most vets rely on presumptive diagnosis.
Early signs of hindgut ulcers include non-specific indications of mild intermittent or recurring colic, lethargy and loss of appetite. However, as the condition worsens clinical signs may include:
- Sudden girthiness
- Sensitivity in the flank area
- Difficulty bending, collecting, and extending
- Blood in the manure
- Chewing wood
You can perform a quick test at home by testing the pH of your horse's manure.
Manure Test for Hindgut Acidosis
So a few disclaimers first... this is not a substitute for veterinary advice. Secondly, make sure you follow the instructions on your strip test pack - as there may be different requirements.
And one more warning.. this is messy. Wear gloves!
- Purchase a pH strip pack. You can get these on eBay for less than $10.
- When your horse passes manure, get 3 - 4 'balls' and place them in a ziplock bag. This is to get a 'cross-section' of the manure.
- Knead the ziplock bag to combine the manure.
- Open the bag and gently place the strip on the mixed manure. Allow enough time for the strip to soak up moisture and for the colour to develop.
- Compare this colour to the pH chart on your kit.
The normal pH for horse manure is 6.8. Anything lower than 6.5 indicates an acidic digestive tract and likely points to hindgut acidosis.
What are the causes of hindgut ulcers?
Bute & Banamine: Bute works by blocking two enzymes. One enzyme is responsible for pain and inflammation and that's the one we want to block for pain relief. Unfortunately, another enzyme is also blocked and it maintains a healthy gastrointestinal lining and also promotes proper blood clotting. This is why it's important not to use non-steroidal anti-inflammatories for longer than 5 - 7 days.
Too much grain: A build up of lactic acid kills off the 'good' bacteria and promotes the growth of pathogenic bacteria. This occurs when too much undigested grain reaches the hindgut. This is called hindgut acidosis.
Stress: When a horse is stressed, they release a hormone called cortisol which prevents the synthesis of prostaglandin. Prostaglandin is vital for mucous production which protect the digestive tract from acid.
Parasites: Parasites, in particular tapeworm and large strongyles can cause ulcers at the site where they attach to the intestinal wall.
How to Treat Hindgut Ulcers
Successful treatment is best achieved through lifestyle changes, diet modification and medication.
- Avoid the use of NSAIDs (especially Bute and Banamine),
- Implement methods to decrease stress. This includes access to grazing/turnout, providing company for your horse and minimising travel & competitions during treatment.
- Provide constant access to low-sugar forage and minimise grains or starchy feeds.
Treating Hindgut Ulcers with Sucralfate
Treating colonic ulcers is different from treating gastric ulcers. Medications such as omeprazole are normally used for treating gastric ulcers, but are not effective for hindgut ulceration. Sucralfate is the best known treatment for hindgut ulcers. It is a sucrose and aluminium hydroxide complex that works by binding to the site of ulceration and forming a 'protective coating' over the lesion.
Once sucralfate binds to the lesion site, it also stimulates the production of prostaglandins – a protective chemical that enhances protection of the colon from further damage.