If the kids are only 12 weeks old I would be careful with copper. I was told a while back to be very careful giving copper to goats under 6 months old. I would definitely talk with the vet on that. I absolutely agree. You can not go solely on FAMACHA. I've been working on fecals and deworming/cocci treatment this past week. While most of ours do not have much in the way of stomach worms, many of our does had a rise in cocci. The 3 you wouldn't think had a higher stomach worm egg count, are the 3 that have good FAMACHA scores and 2 of those have excellent body condition. Maybe they can handle higher worm loads, I don't know, but because we are getting some ready for breeding, and some ready for show, we are not messing around and we are treating them.