Chickens eat rocks, or grit, to aid digestion by grinding food in their gizzards, as they lack teeth to break down hard food items effectively.
If you’ve ever seen chickens pecking at small rocks, you might wonder why they do it. Chickens eat rocks (called grit) to help digest their food since they lack teeth. These rocks stay in their gizzard and grind food into smaller pieces.
How Chicken Digestion Works
Chickens have a unique digestive system that relies on grit to break down food. Here’s how it works:
- Food enters the crop (a storage pouch)
- Moves to the proventriculus (stomach) for acid breakdown
- Passes to the gizzard where grit grinds it up
- Nutrients are absorbed in the intestines
Without grit, chickens can’t properly digest their food. This can lead to serious health issues like sour crop or impacted digestion. Learn more about chicken behavior that might seem strange but serves important purposes.
Types of Grit Chickens Need
Not all rocks work equally well as grit. Here are the main types:
| Type | Size | Best For |
|---|---|---|
| Starter grit | Sand-like | Baby chicks |
| Regular grit | Small pebbles | Adult chickens |
| Oyster shell | Crushed | Calcium source (not true grit) |
How Much Grit Do Chickens Need?
Chickens naturally regulate their grit intake. A study by Poultry Science found chickens consume about 1-2% of their body weight in grit weekly.
When to Provide Additional Grit
While free-range chickens often find enough grit naturally, you should provide extra in these situations:
- When confined to a small run
- During winter when ground is frozen
- When feeding whole grains or fibrous foods
- For chicks being raised indoors
Proper chicken nutrition includes making sure they always have access to appropriate grit.
Potential Problems Without Grit
Chickens without enough grit may develop:
- Impacted crop: Food gets stuck in the digestive tract
- Nutrient deficiencies: Poor food breakdown limits absorption
- Sour crop: Food ferments instead of digesting properly
Signs Your Chickens Need More Grit
Watch for these warning signs:
- Undigested food in droppings
- Decreased appetite
- Weight loss despite eating normally
- Lethargy or reduced activity
Choosing the Right Grit
Commercial poultry grit is specially sized and cleaned. Avoid using:
- Large rocks that could cause obstructions
- Sharp stones that might damage the gizzard
- Sand (too fine for adult chickens)
According to University of Minnesota Extension, insoluble granite grit works best for most chickens.
Fun Facts About Chicken Grit
- Chickens instinctively know when they need more grit
- Grit stays in the gizzard for weeks before being passed
- Turkeys consume up to 0.5 lbs of grit per week
- Ancient birds used gastroliths (stomach stones) just like modern chickens
Now that you understand why chickens eat rocks, you can ensure your flock has proper access to grit for optimal digestion and health.