Does anybody have any ideas or experience in spraying flies with something that makes their wings not work? I want to spray the flies that are in and around the chicken pen, so don't want to use something poisonous. Is there some kind of spray stuff which will stick to the fly after you spray it on (and cause the wings to stick together) so they can't fly? (Then the chickens can eat the flies! A fitting end to the miserable little pests.) Any ideas are much appreciated.