This Roger Corman produced movie about the dubious sport of cockfighting probably occupies similar ground to Cannibal Holocaust in a way. They both exploit animal violence for their goals but those goals stretch beyond mere schlocky entertainment (and I have to say that CH is no more hypocritical than the people who condemn it and then chow down on burgers).
True there are actual cockfighting scenes in the movie and real animals were harmed and killed and the fights themselves are presented in a very grim way, so animal lovers are advised to stay away. But Cockfighter is also a Monte Hellman movie and not content with wadding its way through schlock. It's similar in many ways to his masterpiece Two-Lane Blacktop in that it is an understated character study disguised as something else (in Blacktop's case a road movie, here a movie about cockfighting), introvert and contemplative without any pretense and stripped of all fat.
Warren Oates almost totally silent performance is great, relying on glances and gestures and understated enough to suck you in his character's tormented psyche like a Lon Chaney of 70's hardboiled cinema. His character is reminiscent of the G.T.O. he played in Blacktop three years earlier, once again a drifter, a man that has fallen out with society and himself and is now trying to come to terms with life in his own way. As is true for other Hellman movies and his great talent, things are never spelled out but are left vague as if incomplete but still carrying all the meaning they're supposed to carry. The puzzling ending is another example of this and I think the movie is better off because of it.
Newcomers to Hellman's movies might wanna start elsewhere and work their way to Cockfighter. This is still characteristic of his work and Oates is in top form, but it's not as good as Blacktop although maybe more accessible. A must-see for fans of Sam Peckinpah too.