Cows, hens, sheep and pigs

The cows in the field
Say, "Moo" and yield
Their milk for the farmer to sell.
Some is made into cheese
And, for all to please, butter and yoghurt as well.

The hens in the yard
Work very hard  -
Lay eggs for the farmer to sell.
Boiled, poached, fried,
If you really tried,
You could whip up an omelette as well.

The sheep in the field
Say, "Baa" and yield
Their wool for the farmer to sell.
It's used for knitting
And, it's only fitting,
Some is turned into suits as well.

The pigs in the sty
Say "Oink" and cry,
"It's US that the farmer will sell.
Pork, ham, bacon:
If we're not mistaken,
We'll be made into sausage as well!"