What is the function of a chicken's gizzard?

The function of a chicken's gizzard is primarily to grind food. Chickens do not have teeth, so they rely on their gizzard, a muscular organ, to break down hard food particles. The gizzard contains small stones or grit that the chicken ingests; these help in the mechanical process of grinding the food, which is critical for proper digestion.

In chickens, the digestion process occurs in stages. After food enters the crop for storage, it moves to the gizzard where it is thoroughly mixed and ground. This grinding action facilitates the breakdown of food into finer particles, making it easier for digestive enzymes to work effectively when the food moves into the next stage of the digestive tract, the intestine. Hence, while the gizzard does play a role in the overall digestive process, its primary function is to grind food, which supports the subsequent stages of digestion and nutrient absorption in the intestine.