Ah, yes...there's an article:That would probably be R2elk in Natrona county, WY.
https://www.backyardchickens.com/articles/alternate-method-to-prevent-water-freezing.73180/
Says: "I normally replace the manure annually.
I prefer to use horse manure but since I no longer have a horse, I use the chicken droppings that I collect from under their roosts."
Hey @R2elk ....this still working for ya?