Steers: Steers have similar conformational qualities as bulls do, except that they lack that testicular sac between their legs and their navel or sheath is much less defined. However, steers still retain the hair hanging down from the middle of their belly, and this is, like bulls, where their penis is housed and where they urinate from. This little hair is pretty much the only way to tell if this animal you are looking at is a steer. Steers typically appear more feminine than bulls do, lacking the characteristic muscular hump and depth over the neck and shoulders. Sometimes, when steers and heifers are living together, the only way to tell if the animal you are looking at is a steer is that the vulva, present only in heifers and cows, is absent. If there’s nothing else under the tail except the anus, and said animal has no testes, then it’s a steer.

Steers are not born as steers, they are born as bull calves and are made into steers by the process of castration.

Cows: The best way to tell if a bovine or cattle-beast is indeed a cow is to look between the hind legs and see if an udder is present.  If you look under the tail (if you can’t you can see it when the tail is swishing flies away or for some reason or other, is held to the side), you will see a slit with a prepuce hanging down from it. This is where the vulva is located, the area where cows (and heifers) urinate from, accept the penis of bulls to be bred, and where their calves are born from. All cows have this, and it is a bit more defined and larger in cows than in heifers. Vulvae are located below the anus.

Bulls: Bulls are typically massive beasts. When they are among the cowherd, it’s pretty easy to pick out the bull among the herd because of his larger size and masculinity in comparison to the more feminine-looking cows or heifers that he is with. Not all bulls have horns. The only way you are really going to tell if it’s a bull or not is to look to see if there is a large football-shaped sac hanging down between his hind legs.

Stag: a male bovine (or bull) that has been castrated after or upon reaching sexual maturity and is primarily used for beef, but can and is also often used as a “gomer bull” for detecting cows and heifers in heat.

Get the point?  It has never been the case that castrating a Bull makes it into a Cow or a Heifer.  Just a Steer, a male bovine (or bull) that has been castrated before reaching sexual maturity and is primarily used for beef. 

And on the farm or ranch, the Bulls, Steers, and Cows all go to the bathroom in the same place.  Because they’re animals.