I got 5 chickens from an Amish auction about a month ago and some of them had scaly legs when I got them. thought it might have been from previous upkeep so I didn't do anything right away. I was reading some stuff about it, and saw things like WD-40 and Kerosine(From a 1958 chicken book). Is there anything "around the house" I could use, don't have either of these. How often should I put it on? Why do only some of the chickens have it?