No Fast Food for Cows

I love the sight of cows lying in the field, chewing their cud. But what is cud? And why do they spend so much time chewing it?

Cows first fill their stomachs with grass and other food. Then they settle down for a good long chew. They bring the food back up from their stomachs and rework what they’ve already eaten, assimilating its goodness and transforming it into rich creamy milk. Time-consuming? Yes. A waste of time? Not if they want to give good milk.

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