Any thoughts on this: out of 13 2-3 y/o hens I am getting maybe 1-4 eggs a day! They were laying like crazy and have cut way back. I saw them a month or so ago in a part of our yard that had standing water from our septic drain field and drinking it! Could this cause the slow down in eggs? Maybe cause worms? What should I do? Been trying to keep an eye on their poops and they seem somewhat normal. I also noticed some lice on some & been dusting them with DE & cleaned out the coop. At a complete loss as to why!