Owls are imprint birds. So the first thing they see when hatched out that feeds them is ‘mummy’.
Our pub landlord has an imprint duck. Poor thing has has claws (webbed feet disappeared as it no longer swims/paddles), waddles around in a small cage, tiny pond and takes a lot of looking after.
Small goats need injections, regular hoof/nail clippings and don’t always eat everything.
Edit – just remembered the ‘KuneKune’ breed of pig is ideal as a pet, miniture pig, however they can grow to quite a large size, very cute though!
Not sure about pigs, but if my memory serves me well these are the easiest to look after.
Please realise most goats and pig prefer company, so maybe get a couple at least in the pen/field.