Part of ScienceBody systems
In this video, learn how barn owls and cows digest food and get rid of waste.
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Find out how animals digest food and get rid of waste
Gather round children.
We鈥檝e come to the countryside to meet animals who digest their food in different ways, starting with the barn owl.
Barn owls eat small rodents like mice, but since they don鈥檛 have teeth to chew with, they usually just swallow them whole.
The only problem is digestive juices in their stomachs aren鈥檛 strong enough to break down bones and fur, so instead, all that tough stuff gets compressed into pellets inside the owl鈥檚 gizzard, which is like a muscular second stomach.
A few hours after a meal, the owl will spit up the pellet of compressed waste.
Here comes one now.
Heads up!
MOOING
Cows eat grass which is very difficult to digest, so their stomach has four separate compartments to help process it.
In the first compartment, bacteria starts to break down the grass, and in the second, the grass gets shaped into balls called cud.
The cud travels back up the cow鈥檚 throat and gets chewed a second time to break it down even more.
In the third compartment, the cud gets packed tight and loses most of its water, and in the fourth, the cud finally gets broken down by digestive juices.
Nutrients are absorbed in the intestines and any undigested food and nutrients are treated as waste, which goes all the way throughthe cow and comes out as poo.
What may be waste to a cow, of course, can still have nutritional value for others.
Waste not, want not I say!
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