I took 4 poults up to my farm 2 hours away Friday. The 12x12 pen has been empty for over 2 months this pen housed these poults parents before I brought them here. The pen is built next to the chicken pen. But the chickens can't get inside the pen. They had 5 gallons of fresh water and 30 lbs of Purina game bird starter in the pen. They were running around peeping and eating all weekend inside the pen I left from there yesterday around noon came home. I got word at 750 am one was dead one was sickly acting. Other 2 were running around fine eating and chirping. Got word at 230 the sickly one and one of the normal ones was dead. No animals got to them. Does blackhead work that fast?