Minecraft wiki entry for Goat, associated text: The goat's third hurt sound (screaming) and its first ramming preparation sound (also screaming) are the same, but pitched differently; the former is pitched higher than the latter.
The goat's fourth death sound (regular) is its first ambient sound (also for regular goats) but lower pitched.
The goat's second ramming preparation sound (screaming) is its fifth ambient sound (also screaming) but higher pitched.
The goat's first and third ramming preparation sounds (both for screaming goats) are its first ramming preparation sound (regular goats) but heavily edited.