Laminitis, also known as founder or foot fever, is a painful and potentially devastating condition affecting the horse’s hooves. It results from reduced blood flow to the laminae, the soft tissues that suspend the pedal bone inside the hoof capsule. When these tissues become inflamed or damaged, the connection between the hoof wall and the bone weakens leading to severe pain, structural collapse, and in some cases, euthanasia.
What Is Laminitis?
Laminitis is a condition where the blood flow to the laminae is compromised, leading to inflammation and breakdown of the structural support within the hoof. It’s comparable to the area under a human fingernail becoming inflamed except the pain is magnified and felt across the entire hoof.
Laminitis can be:
- Acute: Sudden onset, very painful, often a medical emergency
- Subacute: Less intense but still painful, requiring immediate care
- Chronic: Ongoing or recurring episodes, usually following earlier acute events
It typically affects the front hooves, but all four feet or only the hind hooves can be involved in some cases.
What Causes Laminitis?
There are several well-documented causes, including:
Diet-related causes (most common):
- Overconsumption of grain (starch overload)
- Grazing lush, sugar-rich pasture
- Sudden access to high-fructan grasses like perennial ryegrass
Metabolic disorders:
- Equine Metabolic Syndrome (EMS)
- Cushing’s Disease (PPID)
Systemic illness:
- Endotoxaemia from colic, infections, or retained placenta
- Excessive use of corticosteroids
Mechanical stress:
- Hard work on unfit horses, or prolonged concussion on hard ground
Recognising the Signs of Laminitis
Acute Laminitis Symptoms:
- Reluctance or refusal to walk
- Abnormal stance (leaning back to take weight off forelimbs)
- Hot hooves with a strong digital pulse
- Pain, depression, trembling, elevated heart and respiration
- Often accompanied by a fever
Subacute Laminitis:
- Milder stance and lameness
- Heat in hooves and digital pulse still present
- Still requires urgent veterinary care
Chronic Laminitis:
- Long or curled hooves, rings in the hoof wall
- Changes in hoof shape (narrow or elongated)
- Ongoing or intermittent lameness
- Possible pedal bone rotation or sinking
The Link Between Diet and Laminitis
High levels of starch and sugar in the diet are fermented in the horse’s hindgut, leading to:
- Lactic acid buildup
- Disruption of gut bacteria
- Release of endotoxins into the bloodstream
- Vascular damage in the hoof
Inflammation and breakdown of the laminae
Fructans, storage sugars in some grasses, are particularly risky. Grasses like perennial ryegrass can contain up to 12% fructan, while safer options like cocksfoot may have only 2%. Sugar content varies with time of day, peaking at dusk and lowest at dawn.
Managing a Horse or Pony With Laminitis
Management should focus on diet, movement, and veterinary diagnosis:
- Feed mature, grassy hay-soak for 30 minutes to reduce sugars
- Avoid all grains and grain-based feeds
- Feed low NSC feeds such as Coolstance copra meal
- Use a broad-spectrum supplement like Equilibrium Mineral Mix to replace minerals lost during hay soaking
- Provide non-grassy yards or dry lots to allow safe movement
- Do not restrict access to feed
- Provide low NSC in hay feeder or hay nets
- Encourage constant gentle movement to improve hoof circulation
- Test for Cushing’s Disease or Equine Metabolic Syndrome
What Horse Owners Can Do
Laminitis is largely preventable with good management. Here's how to reduce your horse’s risk:
- Maintain a healthy body condition—overweight horses are more prone to laminitis
- Choose low sugar, high-fibre feeds like copra meal, unmolassed beet pulp, or soybean hulls
- Only feed grain when necessary, and limit to <0.5% of body weight per meal
- Never feed grain to horses with EMS, Cushing’s, or a history of laminitis
- Monitor NSC (non-structural carbohydrate) content in pasture and hay
- Restrict grazing to early morning hours when sugar levels are lowest
Avoid high-NSC species like ryegrass and plantain
- Be cautious with lucerne (alfalfa)—introduce slowly, stop feeding if negative signs appear
- Ensure the diet is fully balanced for energy, protein, vitamins, and minerals
Why Movement Matters
In nature, horses roam 8–26 km per day. This constant movement:
- Stimulates hoof circulation via the frog
- Supports healthy hoof structure
- Helps prevent metabolic issues
To mimic natural behaviour:
- Spread feed and water far apart
- Create safe, movement-friendly paddocks
- Avoid confinement, even if exercise sessions are scheduled
Stance Supplements
Final Thoughts: Prevention Is Better Than Cure
Laminitis is one of the leading causes of death in horses worldwide, and once severe damage occurs, treatment options may be limited. But with the right knowledge, feeding practices, and lifestyle management, most cases of laminitis are entirely preventable.
Understanding how diet, hormones, and exercise contribute to laminitis empowers you to make informed decisions, protecting your horse from pain, injury, or even euthanasia.
