Usage of "it" pronoun for animals [duplicate]

Possible Duplicate:
Use of “it” and “its” for people and animals

I’m an Italian working in an English-speaking company. In school here they usually teach us to refer to animals using the it pronoun. Something like (i.e. talking about a dog):

It’s really nice.

I see many people using he or she also for animals. What’s the correct way to use it? Should I use it only for inanimate things?

Solution 1:

If you know a creature’s gender, you use he or she. If you don’t, then you use it. Sometimes this is useful for disambiguating.

A cow produces milk for her calf, but people drink it, too.

That rooster’s infernal cockle-doodle-do is going to get him consigned to the soup pot.

A hen won’t lay eggs if she doesn’t have a rooster around.

My garbage was dumped over by a mother bear and her two cubs two nights ago.

The bull moose appeared right in the middle of my path, so I had to go around him.

In all those cases, the gender of the critters is a given, so it makes sense — and is useful — to use a gendered pronoun to refer to them. Notice how in the first sentence, if you replace her with its, things begin to sound weird and ambiguous.