Like many a Troma release, the plot of Poultrygeist comes secondary to how many gruesome ways a human can be torn apart by zombies. Thus, the trailer has very little of the story (as you might suspect, it has something to do with zombie chicken-people), but it more than makes up for that with its varied methods of decapitation, cannibalism, and disembowelment--a surprising number of which begin at the asshole. Your day will not be complete until you see a man's skull cracked open, his brains spilled across a griddle like so many scrambled eggs.* And it's not safe for work, if you hadn't figured that out already.
*It's obvious the brains are literally scrambled eggs.