yep I have around 20 dogs on the yard and just three have it . it just happens sometimes no matter the routine or cleanliness of the dogs . their body's just get out of whack and it will flare up . the sulfadine shampoo sold at most feed stores and tsc have the right ingredients to solve the problem and cephalexin or fish phlex will put them back in order .
I can't imagine having 20. I got 4 and they are plenty lol