The only reason I care about animal welfare is because I think they're probably conscious, capable of feeling fear and pain.

While I agree that this is the case for many animals, I would say that consciousness and emotions are two largely orthogonal things. Certainly consciousness is conceivable without emotions, and having emotions without consciousness also seems plausible. You can have fear and distressing pain without a reflective awareness of being a self with those feelings.

Yes, that is the definition of consciousness (you care about them).