Depends on your goals. I would say you need more than 2 acres if you will want to grow food and have animals.
Discussion
Gotcha, we've got chickens on .5 acres... would want more chickens but probably no cow then?
Goats possible?
I think we could do some fruit trees and probably double our garden
You could keep goats (2 or 3) but would need to buy hay/feed for them. Not enough room for a cow. Every animal needs a buddy for company. Definitely enough space for a good garden, fruit trees and chickens.