My goats had lice coming into the spring i noticed them from the way the goats were itching i dont think they had them for long as the behavior was only for a bit so i bought a treatment and treated them and the lice seemed to disappear within 2 days i could see any adults so i did the follow up treatment as well 3 weeks later still not an sign of anything alive but the eggs or shells of the eggs are still in the hair and it looks terrible like bad dandruff. Now i wouldnt be to worried as i know they are dead an i can treat again as a precaution but it looks so bad to see it is there any way to get the eggs out of the fur without just waiting? i bought shampoo to give them a bath but i dont know if that will actually get rid of the eggs, i was leaning more toward trimming the goats as i planned on this anyway to get rid of that winter coat now that its warming up.
I know that you didn't get a reply right away but I've successfully used apple cider vinegar and lavender essential oil treatments on lice for my kids (human ha!) and it's actually more effective than chemical treatments. The key is to understanding the life cycle of lice and interrupting it. Vinegar helps loosen the eggs from the hair. Lavender kills and prevents. Hope you found a solution!!