15,000 would be a couple of loads of live chickens, give or take.I'm not sure how many chickens they would have in a building, but that was probably all that was left in there. Most of the buildings I haul out of have 40 to 55 thousand starting with new chicks. There are all kinds of things to consider with poultry/
Usually a house has about 20 to 30k of chickens, depending on the size of the house...avg production of a live kill facility is 250k per shift, so yes that was a lot of chickens. But the important thing is to note that it was caught, it was contained, it was dealt with.