Apparently they have a breeding cycle that lasts 5-9 days, and twice during that cycle they do not feed, not counting the time in the egg. That is the reason you have to treat for 4 weeks, 4 times. If you use cydectin, it is longer acting than the ivomectin and you only have to treat twice, once every two weeks instead of the once a week with the ivomectin which wears off their skin faster.
Laney
Laney