Squeal like a stuck pig

Pig sticking was a British cavalry sport in India first attested in 1820 according to the OED. Cavalrymen armed with lances would hunt wild pigs and stick or spear them. It is not surprising that a pig speared in this way would squeal. Towards the end of the 19th century, the expression was being used figuratively to describe any animal, human or otherwise, that emitted loud squeals.