I have been deworming my chicken with Fenbendazole AKA Safeguard 15cc per gallon of water 1 week apart. I did this about a month ago and today when I was cleaning their coop I saw some worms. It had been almost 3 weeks since I cleaned the coop, is it possible that worms or larvae could have came from outside or do my chickens have worms?
Are you certain that you saw worms, or might they have been maggots?