To summarize, I made a world and walked around in a plains biome, where I encountered horses with glitched textures.

What I expected to happen was...:
A normal horse texture.

What actually happened was...:
The horses had glitched textures, with most of it missing, parts of the head being the front of a chest texture, and hooves.

Steps to Reproduce:

I made a world and explored and encountered this bug.