I have never wormed my birds, but I figured that it would be a good idea to treat them once or twice a year. I really didn't want to get the kind you put in the water so i got "Privermectin Pour-On for Cattle". I've read certain posts that say that 3 drops are a good dosage for average sized bantams. Do I only give it once, or do I give it again 10 days later? For those of you that are experienced what do you think of this plan? Thank you!