MOO. moo.

the mother cow goes MOO
while a half cow goes moo

(the half cow sure is a calf
 no, no, definitely no giraffe

a giraffe is something very tall
if you thought you knew it all)

the mother cow MOOs in capital letters
that the squeaky calf's moo easily betters

say what you may, blah, bleh, blub
a calf is only a cow's cub!