Ivermectin is NOT approved for use in poultry and has no stated withdrawal time. I would use that ONLY as a last resort.
Permethrin on the other hand is approved, works GREAT on lice, and has NO withdrawal period if used according to directions. I like the spray because it's SO easy to use. I part the feather near the vent, under the pits, and at the nape of the neck. Chickens get body, head, or feather lice. And the head lice may never travel to other part of the body to be treated.
Many vets will refuse ivermectin for chickens since it is an off label use. I would only go that route if I had depluming mites or something that the permethrin won't work for.
Also, mine was bought/labeled as horse fly spray. I bought it to keep mosquitoes off my goats and discovered it had other uses for my pets/livestock. That ready to use bottle was under $10 and had lasted 60+ chickens, 3 dogs, and 2 goats, plus roosts, nests, walls or whatever... for more than a year. And after seeing feather damage I was concerned wasn't being treated took a hen to the vet, who said "there used to be something, but no current evidence of parasites". In other words (Yes I had lice, I saw them), but the permethrin was effective.
Also, if you currently chase your birds to treat... try treating after they go to roost at night and keep it dim using a flashlight. Most birds should stay put where they are and no chasing required!
Good luck, pests are a pain.
Permethrin on the other hand is approved, works GREAT on lice, and has NO withdrawal period if used according to directions. I like the spray because it's SO easy to use. I part the feather near the vent, under the pits, and at the nape of the neck. Chickens get body, head, or feather lice. And the head lice may never travel to other part of the body to be treated.
Many vets will refuse ivermectin for chickens since it is an off label use. I would only go that route if I had depluming mites or something that the permethrin won't work for.
Also, mine was bought/labeled as horse fly spray. I bought it to keep mosquitoes off my goats and discovered it had other uses for my pets/livestock. That ready to use bottle was under $10 and had lasted 60+ chickens, 3 dogs, and 2 goats, plus roosts, nests, walls or whatever... for more than a year. And after seeing feather damage I was concerned wasn't being treated took a hen to the vet, who said "there used to be something, but no current evidence of parasites". In other words (Yes I had lice, I saw them), but the permethrin was effective.
Also, if you currently chase your birds to treat... try treating after they go to roost at night and keep it dim using a flashlight. Most birds should stay put where they are and no chasing required!
Good luck, pests are a pain.