Avian digestive system

Introduction:

Everyday I see so much animals. Specifically, I see one type of animal so much, flying in the air. What do you think it is? Here is one hint- It will have a beak. The answer is birds. You may have seen the external structure of the birds. But, have you ever wondered what will be in the birds and how they eat? We will discuss about how the birds eat today.

We humans have the Human digestive system

But, bird like animals have a other digestive system known as the avian digestive system.

In the human digestive system there are some body parts that we don't have but it will be in the avian digestive system. For example, the gizzard.

Process of digestion:

    We will discuss about what happen when the animal eats. Before that, we shall take an animal that has the avian digestive system. That is, we can take birds. So when birds eat, they don't bite or grind or crush it. Instead, they will swallow it. It is because birds don't have teeth. So we can say birds will eat un-masticated food. The un-masticated food goes from mouth to the esophagus. Food reaches the crop. From the crop, it goes through the proventiculus. The gastric juices from the liver and pancreas meet here. The food then goes to the gizzard. Small stones which may have come while they were picking up the food are stored in the gizzard. Then food goes to small intestine to large intestine. There will be some waste left over. The uric acid from the kidney is secreted to large intestine and it mixes with the waste and comes out by the cloaca. The waste will be in a semi-solid structure.

So if you notice closely, there are 2 stomachs in the avian digestive system.

1. Proventriculus
2. Gizzard

Crop- Stores food temporarily

Proventriculus- place where gastric juices from liver and pancreas join together- Enzymes are also formed in proventriculus- This causes breaking down of food- It is the 1st stomach

Gizzard- Place where food is stored and it will be crushed, grinded- Stones which come while the animals pick up their food are stored in the gizzard

Small intestine- Plays a very important role in digestion and absorption

Large intestine- Absorbs the nutrients and the minerals from the undigested food