Horse Hoof Frog: What It’s Made Of & How It Works

When it comes to equine care, most people focus on the outer hoof wall or the shoe, but one of the most important parts of the hoof is often overlooked—the frog. That soft, triangular piece in the middle of the hoof might look small, but it plays a huge role in your horse’s comfort, movement, and health.

Whether you're a professional farrier or a horse owner who wants to understand your horse’s hooves better, knowing what the frog is made of and how it works can help you provide better care. In this guide, we’ll explain everything you need to know about the horse hoof frog in clear, simple language.

What Is the Frog in a Horse’s Hoof?

The frog is the V-shaped structure located on the bottom of a horse’s hoof. It sits between the heel bulbs and extends toward the toe, taking up about 25% of the hoof’s sole surface.

It may look soft compared to the hard hoof wall, but it’s made of tough, rubbery tissue that helps with shock absorption and blood circulation.

What Is the Frog Made Of?

The frog is made of a special type of keratin, the same protein that makes up the hoof wall, hair, and skin. However, the frog’s keratin is softer and more elastic.

This elasticity is due to:

• Higher moisture content than the rest of the hoof
  
  

• Looser keratin structure
  
  

• Thicker layers of epidermal tissue
  
  

The frog also contains nerve endings and small blood vessels, especially in the deeper parts, which help detect pressure and assist in circulation.

Main Parts of the Frog

Understanding the frog’s structure helps explain how it works. It has three main regions:

1. Apex – The pointed front of the frog, closest to the toe
   
   

2. Central Sulcus – The center groove that runs down the middle
   
   

3. Collateral Grooves – The deep lines that border the frog on both sides
   
   

Each part has a job:

• The apex helps guide weight distribution
  
  

• The central sulcus allows flexibility
  
  

• The collateral grooves help shed debris and bacteria
  
  

What Does the Frog Do?

The frog does more than sit on the bottom of the hoof. It performs several key functions that support your horse’s entire body.

1. Shock Absorption

Each time a horse takes a step, the frog acts like a cushion. It absorbs some of the impact that would otherwise stress the bones, tendons, and joints.

Fact:
A horse weighing 1,000 lbs can place over 2,000 lbs of pressure on a single hoof during movement. The frog helps reduce that force.

2. Blood Circulation

The frog works like a pump. When the hoof hits the ground, the frog presses against the ground, helping push blood back up the leg.

This is essential because the horse’s lower legs have no muscles. The hoof must do part of the job of moving blood and keeping tissues healthy.

3. Grip and Traction

The soft texture and unique shape of the frog give horses better traction on slippery or uneven surfaces. It also helps stabilize the hoof as it lands.

4. Balance and Feedback

Because the frog has nerve endings, it provides feedback about the ground. This helps the horse balance, adjust its step, and detect pain or pressure.

How the Frog Changes Over Time

The frog’s size, shape, and condition can change based on:

• Age
  
  

• Breed
  
  

• Activity level
  
  

• Terrain
  
  

• Health
  
  

Healthy frogs are:

• Wide
  
  

• Firm but springy
  
  

• Slightly moist (not dry or mushy)
  
  

• Even on both sides
  
  

Unhealthy frogs may become:

• Cracked or flaky
  
  

• Infected with thrush
  
  

• Shrunken due to poor circulation or lack of use
  
  

Stat:
In horses kept in stalls or soft ground, frog size can shrink by up to 30%, which affects circulation and shock absorption.

What a Healthy Frog Looks Like

A healthy frog should:

• Take up about ⅓ of the hoof’s bottom
  
  

• Be symmetrical with even collateral grooves
  
  

• Be dark gray to black in color (varies by breed)
  
  

• Have no foul odor or discharge
  
  

Signs of an Unhealthy Frog

Watch for these signs that something may be wrong:

• Foul smell (could be thrush)
  
  

• Deep central crack (can trap bacteria)
  
  

• Mushy or soft frog (sign of infection or over-moisture)
  
  

• Pain when touched
  
  

• Bleeding or flaking
  
  

These are signs of problems like:

• Thrush – Bacterial infection of the frog, often black and smelly
  
  

• Canker – A more serious infection that causes abnormal tissue growth
  
  

• Fungal infections – Caused by wet, dirty conditions
  
  

• Frog atrophy – When the frog shrinks from lack of pressure or movement
  
  

Frog Care in Daily Equine Care Routine

Caring for the frog doesn’t require special tools—just consistency and cleanliness.

Daily Care:

• Pick hooves at least once a day
  
  

• Clean the central sulcus and collateral grooves
  
  

• Watch for signs of infection or pain
  
  

Weekly Care:

• Brush off mud and manure
  
  

• Check for cracks or bad smells
  
  

• Keep the environment dry and clean
  
  

Farrier Visits:

• Every 6 to 8 weeks, have a farrier trim the frog as needed
  
  

• Never cut deep—only loose or dead frog tissue should be removed
  
  

Fact:
Over-trimming the frog can damage sensitive tissue. Ask your farrier to show you where to trim and where to stop.

How to Keep the Frog Healthy

Follow these tips to protect the frog as part of overall hoof care:

1. Dry Environment:
Avoid letting your horse stand in mud or wet bedding. Wet hooves soften and weaken the frog.

2. Movement:
Turnout and regular exercise help the frog function as a blood pump and stay well-shaped.

3. Balanced Trimming:
A well-trimmed hoof keeps weight evenly distributed and reduces frog pressure points.

4. Proper Nutrition:
Feed enough zinc, copper, biotin, and protein to support healthy hoof tissue, including the frog.

5. Clean Living Space:
Pick stalls daily and use dry, absorbent bedding. Moisture and manure allow bacteria to thrive.

Common Frog Problems and How to Handle Them

Thrush

• Signs: Black goo, bad smell, deep sulcus
  
  

• Solution: Clean daily, apply disinfectant, keep dry
  
  

• Prevention: Regular picking and clean footing
  
  

Frog Atrophy

• Signs: Small, narrow, shrunken frog
  
  

• Solution: Increase turnout, trim carefully, add hoof stimulation
  
  

• Prevention: Let your horse move naturally
  
  

Canker

• Signs: Spongy growth, bad odor, bleeding
  
  

• Solution: Requires vet care and aggressive treatment
  
  

• Prevention: Maintain hygiene, avoid chronic moisture
  
  

FAQs: Horse Hoof Frog

1. Should I trim my horse’s frog?
Only trim loose, dead tissue. Never cut live frog. Let your farrier handle deeper trimming.

2. What causes frog infections?
Wet, dirty conditions that promote bacterial or fungal growth are the top causes of frog infections like thrush or canker.

3. Is it bad if my horse’s frog is dry and cracking?
Yes. A dry, flaky frog can lead to cracks that trap bacteria. Maintain a healthy balance of moisture—not too wet or too dry.

4. Can shoes affect the frog?
Yes. Some shoes lift the frog off the ground, reducing its function. Talk to your farrier about shoeing that allows frog contact when possible.

5. What if my horse’s frog bleeds during cleaning?
Stop and clean gently. Bleeding may indicate over-trimming or infection. Let a farrier or vet examine the hoof.

The horse hoof frog may be a small part of the hoof, but it plays a huge role in your horse’s comfort and health. From absorbing shock and pumping blood to providing traction and balance, the frog is one of the hardest-working parts of the horse’s foot.

By understanding what it’s made of and how it works, horse owners and farriers can better care for the whole hoof and prevent problems before they start. Healthy frogs lead to healthy movement, and healthy movement leads to a happy horse.