Can bulls be black and white?

Yes, there are many bulls (intact males) or steers (castrated males) that are black and white. I believe the one you are referring to are Holstein-Friesians.

Other black-and-white breeds include (from the top of my head):

White Park

British White

Texas Longhorns (blue roan coloured cattle)

Speckled Park

Belted Galloway

Dutch Belted

Yaks

Freisian

Black Hereford

Simmental

Gascon