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Digestive System of Birds
January 26, 2015

Is it possible to post the 'sun' as missing?

Can I put a picture of the sun on 'milk cartons' (do they still do that)?

The gloom of winter is more of a challenge for me this year.

This week we have appointment to Yolanda's gynecologist on Tuesday, dental checkup and cleaning on thursday, and Friday to her primary care doctor.

Prayerfully we can get a script, or get rolling on getting the (not used for weeks) feeding tube removed.

PT and OT start at Hope Network also this week.

it was only 2 long, or short months ago, our world was turned upside down.

Praise be to God!

Other challenges for Karen and myself are now mental, and emotional.

We wrestle with, and face issues within.

Thankfully we have a God we can go to in times of need.

Okay, enough.

This week I attempt to tackle a subject i just know you have been wanting to know all about.

The Digestive System of Birds.

In a nutshell...............

They eat a lot, and poop a lot. :-)

It is more complex than that.


The digestive system of birds is complex but extremely efficient.

A small bird can eat up to twenty percent of its body weight daily.

Can you do that?

Birds have an very high metabolism, so to keep up with the requirements bird must eat a large amount of food.

It all begins with the bill or beak, and tongue.

A bird's bill is composed of a number of separate horny plates called rhamphotheca which are made of a protein called keratin much like our fingernails

This keeps the bill growing throughout the bird's life.

Because it continues to grow, it must be worn down by climbing and cracking nuts, pecking at trees, and rubbing objects to keep it it optimal condition.

When a bird eats it uses its bill and tongue to gather food.

(I love to watch Cardinals, chickadees, and other birds work a seed, it is amazing.)

Since a bird has no teeth, chewing time is eliminated.

because a bird does not have to chew its food they can often eat a large quantity of food at one time, instead of sitting there to chew, and becoming a meal for some predator.

Saliva lubricates the food much like in a human so that it can pass to the esophagus.

The esophagus is a tube-like structure which passes food in waves better known as peristalsis, to an organ known as the crop.

The crop separates birds from other animals, as it is an organ that is exclusive to these animals.

The crop's main function is to store food.

The crop is located at the base of the neck and can be easily seen after a bird has just eaten.

The crop continuously supplies small amounts of the food to the stomach.

The food passes from the crop to the stomach, which is the most active part of the digestive system of a bird.

There are two parts to the stomach of a bird.

The first part is known as the proventriculus.

This is the glandular portion of the stomach.

This portion secretes digestive juices which break down the food.

In the dove family, the stomach can produce what is known as crop milk, or pigeon's milk

Both dove parents feed this to their young.

The proventriculus joins a large muscular portion of the stomach known as the ventriculus, or more commonly known as the gizzard.

The gizzard grinds up food even more.

This organ contains gravel, or grit the bird consumes just for this purpose.

(This is why we offer grit to birds, especially in the cold, snows of winter.)

Grit works with muscles in grinding up food.

Some birds have gizzards that are so powerful they could grind up needles of steel in a matter of hours.

In birds that ingest whole seeds a gizzard is very important.

Take a look at Jays and doves for example.

They swallow whole sunflower seeds and peanuts.

(There was a time I thought these birds inhaled the food, went to a safe place, regurgitated and would crack open and break the seed meats down into pieces.)

In these birds digestive enzymes alone cannot effectively break the seed hull.

This is where the gizzard comes in to help.

These birds require a large amount of grit in their diet.

After leaving the gizzard the food is passed on to the small intestine where it mixes with bile and enzymes.

The enzymes help with the breakdown of sugars, fats and proteins.

Bile from the liver breaks down the larger fat molecules.

The nutrients are then absorbed and passed on to the blood stream.

The liver of the bird has two equal lobes and is nestled next to the heart under the rib cage.

Like in people, the liver acts as a detoxifier, purifying toxins that enter the bloodstream and it recycles red blood cells some which are used to create bile.

In some birds the bile is stored in the gallbladder.

The pancreas in birds is located near the small intestine.

The first function of the pancreas is to neutralize acids that are found in the mixture passed on from the stomach.

If this does not occur serious damage could occur to the intestine of the bird.

Another major function of the pancreas is to produce insulin so that all the bird's cells are supplied with glucose.

Whatever does not get digested is passed through the single opening in the urogenital system known as the cloaca or vent.

The waste is excreted in the form of bird droppings.

Birds tend to make droppings often because they have such a high metabolism and eat often.

The dropping should have a white pasty part, this is the urine.

A normal healthy bird should have anywhere from 25 to 50 eliminations a day, and happen at anytime, as most birds have no control over this.

Now, with birds like owls, they also regurgitate undigested matter, like bones, fur, and feathers.

These are called owl pellets, and are often found under a nesting area.

A bird's digestive system is extremely efficient because it has to be to keep up with the metabolic reactions the bird has.

Birds that are fruit eaters can digest berries in thirty minutes, and seed eaters usually digest their food within three hours.

Would you like that kind of metabolism?

Indeed, our Creator has made birds one very
efficient creature, and we need to appreciate them more.

Well, it is time to fly for now.

Before I go, here is your positive thought for the week.

God Bless.

I am not a product of my circumstances. I am a product of my decisions.

Stephen Covey

It's too easy to blame others for our circumstances.

The day you turn 18 years of age, you are responsible for your choices.

You, and you alone are responsible.

Do you want a better life?

You can change.

You can choose.

But if serving the LORD seems undesirable to you,
then choose for yourselves this day whom you will serve,
But as for me and my household, we will serve the LORD."

Joshua 24:15

"Treat the earth well:

It was not given to you by your parents,

It was loaned to you by your children.

We do not inherit the Earth from our

Ancestors, we borrow it from our Children."

Ancient Indian Proverb

Your friend indeed,

Ron Patterson

PS. If you enjoy these letters, please forward them to friends, family and co-workers.

Better yet, have them sign up so they can receive their own letters.

Gardening For Wildlife.

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