I'm curious, how does everyone here treat lice in cattle? We manually spray them from time to time, but I'm assuming this might not be doable for people with large herds. Is there an easier way?
Use a pouron wormer in combination with cheap permethrin fly tag. Pour on when processing in fall/winter and apply fly tag that keeps them down all winter.
I deworm orally and with pour on in October and April, I never have lice problems pouring twice a year, but like dun said, you might get by just once a year.