What is the primary function of a chicken's gizzard?

The gizzard is a specialized muscular organ found in birds, including chickens, that plays a crucial role in digestion. Its primary function is to grind food, effectively breaking it down into smaller particles to aid in the digestive process. Chickens do not have teeth to chew food; instead, they rely on the gizzard, which often contains small stones or grit that help to grind the food thoroughly. This mechanical processing is essential for allowing the nutrients in the food to be absorbed effectively in the intestines.

Storing food is managed by the crop, a pouch located in the esophagus where food can be temporarily held before being passed to the gizzard. Egg production occurs in different parts of a hen's reproductive system, primarily in the ovaries and oviduct, and is unrelated to the function of the gizzard. Nutrient absorption takes place in the intestines, where digested food passes after being processed in the gizzard, thus clearly delineating the separate roles of these organs in a chicken's digestive system.