Enclosure wood

I am building an enclosure for my new 'pet' and I am looking into constructing a custom built case for it.

I have seen that MDF seems to be one of the best materials - but I know that pine and cedar are out. What if the MDF is made out of pine or cedar? how would i know?

I don't think its so much with the building material that pine is out. I mean you can still find herps in a pine forest. Its the Aromic oils that Cedar and Pine have that causes problems. You will have to seal any wood except melamine which is like MDF that is coated in a white plastic like covering. Any wood like Ply needs to be sealed with a couple coats of polyurethane which should keep any pine or cedar smell in. Hope this helps