User blog comment:Jrooksjr/Category and Sub-Category for Animal pages/@comment-409884-20121210173550/@comment-3474542-20121212022803

Unicorns CAN be put in the Horse Paddock. They CANNOT be put in the Horse Stable. Not all cows can go in the Dairy Farm. Since there are no internal lists (except for the Chicken Coop), storage for older buildings has to be verified on an individual basis.

Yes, constructing new Dairy Farms and Horse Stables has been disabled (even for old players). Some buildings appear to be available only occasionally (Sheep & Pig pens). However, existing buildings still work. There do tend to be more bugs and other issues with animals in old buildings.