Any idea what this is? I’ve been dusting for lice, every 7 days for last 3 weeks. Plan to worm them today. Been periodically putting Vaseline on but doesn’t seem to look any better.
That looks like a fungal infection called favus. The usual treatment if miconazole/Monistat or clotrimazole antifungal cream applied to the white chalky area daily. Betadine or povidone iodine 10% is also a treatment. Here are some pictures of favus: https://bitchinchickens.com/2023/01/23/favus-ringworm-in-chickens/