Luckily I haven't had to deal with coccidia the last few litters I've whelped.
I always give my bitches plain unsweetened yogurt or plain kefir several times a week. I also give it to pups when they start eating on their own. And I've also always mixed frozen BilJac with the kibble I feed (for weaning pups).

I have used Sulmet in the past but it didn't work very well and I'd usually go to the Sulfa Trim to wipe out the rhea!