Uhmn. Sorry that no one's posted. I didn't want to, since I'm no specialist, but now I guess I will. o.o;
I worm mine by putting a little pea sized amount on a few pellets, before they get dinner. I try to do a 9 day course for no symptom bunnies, and the full month course for anything that I know have them.
I use panacur. They make a rabbit formula (which I sprung and bought, cause I didn't know what else I could use), but they also make others that you can use. (Dog, I believe? idk. Just a smaller dose...)
I only worm everyone if someone either gets them in their poop, or I'm having a problem with weight gain/loss.
No, you don't really have to do it. But you can. Uh. That's the jest of it. Wish I could say more, but I don't usually worm.. So...
Sorry.