What is the chant about in Chapter 4?

"Kill the pig. Cut her throat. Bash her in."

When Jack finally does kill a pig, as he has intended to do since the beginning of the novel, he fulfills a violent blood-lust that, until then, had remained frustrated. The other hunters share this quality; when they dance and sing about killing the pig, they show that they have succumbed to the thrill of violence. They relish the slaughter, an enjoyment that transcends pride and signifies pure lust. As they cheer on the means by which they mutilate the pig, their painted skin, chanting, and frenzy suggest they have developed their own sub-society, one based on rituals and an almost spiritual worship of blood, violence, and slaughter.