My mother-in-law is Mexican, but the word for "chicken" in her particular dialect is not pollo but gallina.
Probably, in her dialect, it is the same as in the rest of Spanish America where "pollo" is the edible (i.e. dead) chicken and "gallina" is hen. Gallina can also be food, but you'd be talking about a specific type of bird you'd killed to eat (like a stewing hen maybe? or a hen that no longer lays?), and not the generic we-don't-know-where-it-came-from-because-it's-mcnuggets-now chicken.
The same things applies to fish. It's a "pez" until you're eating it (or staring at its glassy eyes on a bed of ice), then it's "pescado" (which means fished or caught, as well as fish one eats).
There's a similar dichotomy in pork where "cerdo" is more often referring to the food, though not exclusively and "puerco" or "chancho" is more often referring to the animal and rarely used for the food. Also, lechón is pork meat, but only from a very young pig...like veal pigs, I guess? I don't think English has a word for pig-veal, but it's delicious! In Louisiana, we'd call it "cochon du lait". Is there a commonly used English word for that?
Generally speaking, there's tons and tons of food specific words in Spanish. I can't claim there's more than in English, but it seems to my subjective ear to be so.
I'm still confused about citrus, and there are fruits and vegetables I don't even know the name of in English.
Man, I'm hungry now.
