A bull bellows.
Bellow.
The sound that a bull makes is usually called a bellow. They also grunt, squeal, and make several other vocalizations.
You write sizzle.
squeak
bacock
baaah
ting
BOOM!
Most English speakers call the sound a snake makes a "hiss."
The sound that a pig makes sounds like "oink". The sound a cow makes sounds like "moo". These are farm animals.
*whistle* like that