Another thing to consider for those thinking chickens would be a nuisance:

Within Newton, residents are allowed to have up to 5 dogs. Dogs are loud and can be destructive and/or dangerous if not supervised or properly cared for/trained  

Chickens are quiet, provide natural fertilizer to the yards in which they live, and provide food. They're relatively easy to care for, and typically hardy for all Iowa weather. 

Just something to think about.