Minecraft horses enclosure?

I kept a lot of animals in fences at minecraft. But do I have to build two floors of horses in horses? Because not that they jump over it… I hate to build a fence and if that is not necessary I just let it stay

You only have to do it if you put a block next to the fence. Then you can go to the block and then over the fence

I think by itself they can't jump at all, only if you can ride that you can

At the beginning I also thought that horses could jump over fences but this is not the case unless you ride them, so one floor fence is enough