I raised 8 bantam silkies last year and fed them a medicated feed up until they switched to a local feed stores layer feed. However, this year I switched at about three weeks to a non-medicated feed (Dumor) and now their poop has a very strong pungent odor. I am pretty sure it's the feed but can't be sure. It's to soon to switch them to the layer feed but the smell is really gross. Any suggestions?