with or without 's

[fungyf_hk]

Do we need ('s) in these sentences:

1.Do you eat pig head or pig's head?
2.Do you eat chicken feet or chicken's feet?
3.Do you eat dog meat or dog's meat?

[Casiopea]

Parts of the animal
the head of a pig ~ pig's head
the feet of a chicken ~ chicken's feet

But

the meat of a dog ~ dog meat (Do you eat dog?)
the meat of a pig ~ pig meat (Do you eat pork?)
the meat of a chicken ~ chicken meat (Do you eat chicken?)

The meat is the animal, whereas the head and the feet are parts of the animal.