I have yet to figure out how to duplicate this bug. It seems that at random times on several different accounts textures will swap between entities. I have observed this to be especially common with maps, either sheep or books taking on a map texture, or a map taking on an item texture. Here is an example:

This is a server, but the problem only shows up client side, other players are unable to see the change. Closing and re-opening Minecraft fixes the issue, but at another random time with another random texture they swap. 

Thank you, 

-BadgerLord777