1. Ire is confused. Spyro needs to eat? Dragons are creatures of magic first and foremost, so their existence is self-sustaining. They can choose to eat if they like, for the sake of taste and experience, but they don't need to.

2. He was still considered a hatchling then, so -- slightly larger.

3. Just as dragons don't need to eat, they don't need to breathe either. Their basic biological processes resemble other beings structurally (they have hearts and circulatory systems, for example) but any external components they need to survive come from magic itself.