I can imagine how bad it would be.
I only had 5 sheep. I treated one and it got rid of the maggots but i'm sure the stuff itself was so strong it was deadly to the sheep too. I had to have it shot a week later.
After that I had them clipped twice a year. That fixed it.
They rarely got wet because when it rained they would all run for the stable while the horse was coming out because it hated the stable in the rain. Fickle creatures.
