Here's another guitar with pigs on it.
For some bizarre reason - perhaps there's a metaphor going on here that I'm unaware of - the three pigs are dressed as cowboys (cowpigs? I've heard of a sheep-pig, but not a cow-pig).
The pig in the middle seems to be wearing a pair of fancy shades and also seems to be playing the harmonica.
See also this similar cat guitar and this other piggy guitar that we found of eBay recently.