An old bull and a young steer stood on a hilltop looking down onto a pasture where a herd of cows was grazing. The young steer excitedly said to the old bull, "wouldja look at them cows?  Wadaya say we run down there and fuck one?" The old bull then says "wadaya say we walk down and fuck'em all?"

It's an old, but good, story.  However, to be correct it should be a young BULL.  As a veterinarian, I can assure you a steer has no interest in fucking anything!!!

a veterinarian of foreign boars?

I'm just a city kid.
Thanks for the correction.

A rancher had three bulls: large, medium and small sized.  Word got around the ranch that a new bull was bought by the rancher - huge and mean.

The large bull says, "He's not getting any of my cows!"
The medium sized bull says, "He's not getting any of mine either."
The small bull says, "If he tries to take any of mine, I'm going to kick the shit out of him!"

The new huge bull arrives and he's bigger and meaner than anyone thought.

The large bull says, "Well, he can have 4-5 of my cows."

The medium bull says, "Sure, he can have 10-12 of mine."

The small bull is kicking and snorting with blood red eyes.  The other two ask him what he's doing.

Small bull says, "I just want to show him that I'm a bull."