Me and my housemate Dom have had this theory for a while, ever since we heard Watch The Throne. On tracks such as Ni**as In Paris, Ye's vocals are somewhat baa-like.
"She said Ye can we get married at the maaaaaaaaaaaaaall..." and "Got my ni**as in Paris and they going gorillas...haaaaaah?"
Listen to the song. Particularly the official video (don't watch it if you have photo-sensitive epilepsy. It has full-blown warnings at the start of the video), which is a live recording of the song. Kanye's singing live is awful, and even more akin to his woolly ovine brethren. Observe: