Poultry lice only on one bird?? but not the rest?

[Ragna]

So I'm trying to understand... I treated my 3 girls one of them is bigger and the others are just baby pullets. My big one is the road island red and she was INFESTED. So I killed hundreds of them and I'm more than certain I missed some I'm going to have to kill tonight or tomorrow... I just ran out of spray and I'm unable to go out right now since I'm watching my niece and I can take her on my motorcycle. I searched my other girls and found NO lice---- they tend to try and stay away from the road island red as much as they can and aren't always too social with her so is it possible that there in fact aren't any lice on my babies? Meaning my road island was the main carrier of them? I don't see any on the babies... but... I'm still going to treat them but I think I may put more focus on my road island red. to try to get the last bit of them off her. I'm just trying to understand why I'm not seeing any on my babies? I was under the assumption that lice will infest the whole flock

 

[snow5164]

Maybe this is just the beginning? I hope you got them all and the babies are saved from it . Good luck

 

[MickWithChicks]

Always assume the whole flock is infested and treat them all. Clear out all nesting boxes and reline with fresh bedding and hydrated lime / diatomaceous earth. Spray all surfaces with Permethrin . Treat girls with moxidectin or ivermectin. I use an ivermectin oral drench for regular (quarterly) treatments, but have seen great results with the pour on on infested chickens.

If you act now you can prevent the others from being impacted.

 

[Folly's place]

Here in the USA permethrin spray is the best choice; approved for use, no egg withdrawal, easy and economical. Clean out everything, and treat everyone.
One of my roosters is the mite carrier here; He'll have many, and nearly none on anyone else. It's irrelevant; must treat everyone and everything, or have big regrets.
While DE is often recommended, don't bother with it. It's bad to inhale and ineffective.
Ivermectin works great, but is not approved. Just avoid using it.
Mary

 

[MickWithChicks]

While DE is often recommended, don't bother with it. It's bad to inhale and ineffective.

I suggested DE due to other recommendations seen here, but I don't actually use it. I do however use hydrated lime (calcium hydroxide) due to its low toxicity and its use in food preparation. Note that this is only in the nesting boxes and is lightly mixed with pine shavings. The nesting boxes are the only enclosed space in my coops due to our mild winters here, and hydrated lime keeps the mites at bay and the dampness away. I occasionally use it on roosts and other areas that see high levels of chicken poo.

Ivermectin works great, but is not approved. Just avoid using it.

As far as I'm aware, Ivermectin isn't approved for use in poultry anywhere. This isn't due to any particular negative reasons, but is only due to a lack of extensive laboratory tests. Australia's leading avian vet Dr Colin Walker BSc, BVSc, MRCVS, MACVSc (Avian health) recommends the exclusive use of an avermectin for all roundworm, hairworm, and all external blood sucking parasites.

If the lice seen in OPs case are non-blood sucking lice (those that feed off feathers), then I agree that the use of permethrin is absolutely the best and safest option.

For roundworms and hairworms, these days there is no reason to use anything else than an avermectin such as Ivermectin (‘Ivomec’) or Moxidectin. These medications are just so safe and effective and of course have the handy side-effect of also killing all external parasites that suck blood. This includes all mites.

[...]

These days use a synthetic pyrethroid such as Permethrin. These are very safe yet just as effective as organophosphates, prevent reinfection for up to four months and do not take the bloom off the feathers. To spray the birds, dilute (usually 10 –20 ml per litre ) into a handheld pump bottle and spray the birds liberally. To dip the birds, pick a warm day, fill a bucket with warm water, add Permethrin at the rate of 10 –20 ml per litre together with a wetting agent (e.g. some children’s baby shampoo or a few shavings off a cake of pure soap such as “Velvet”) and away you go.​

http://www.melbournebirdvet.com/parasite-control.aspx

Ivermectin dosages can be found in the above link. I use an 0.8% oral drench which is specifically covered in the link.

 

[Folly's place]

I've used Ivermectin, and it works fine, but permethrin also works great, as does fenbendazole, and both are approved in the USA. If I use Ivermectin again, it will be because it's all that will work for a particular parasite.
It's off limits for laying hens because it does linger in the yolks, as many products tend to do.
Mary

 

[MickWithChicks]

I've used Ivermectin, and it works fine, but permethrin also works great, as does fenbendazole, and both are approved in the USA. If I use Ivermectin again, it will be because it's all that will work for a particular parasite.
It's off limits for laying hens because it does linger in the yolks, as many products tend to do.
Mary

Fair enough, I completely understand your reasoning. It's always best to stand on the side of caution. You have far more experience with chicken keeping than I do, and you've found a solution that works best for you and that you can recommend to others.

I agree that you should always try the approved treatments before resorting to something with less vigorous studies.

With that said, I do like to read up on why something should or shouldn't be used, and I like to share my experiences. In my short time in chicken keeping I've spoken to many breeders and avian vets and have done a lot of extensive research of my own. Ivermectin was something I researched heavily and spoke to numerous sources to get all the information.

I'm not sure of the figures in the US, but in Australia, we have legislation that sets the allowed limits of traces of administered drugs within our food sources (meat, milk, eggs, etc). Ivermectin in milk is legal to 0.05 mg/kg (50 µg/kg), but hasn't been measured for eggs. Everything else within the legislation that has both milk and eggs have the residual limits at exactly the same. The only study I can find found that peak residual ivermectin from an oral drench in egg-yolks was measured to 0.0019 mg/kg (1.9 µg/kg). Peak residual ivermectin from a subcutaneous injection was the maximum residual seen in yolks at 0.023 mg/kg (23.3 µg/kg). The study didn't measure pour-on.

All of the above figures are well below the legislated maximums for consumption. I just personally don't see the harm in using Ivermectin, nor do I see the point of a withholding period in eggs with such low measured residual amounts.

I do agree that a permethrin spray should be tried first though. It's much easier to source and there's far more science to back it up.

 

[Folly's place]

Different countries, different rules. And over time, rules change. Who knows how things will look in another five years? I do try to stay within approved guidelines, and best practices, and realize that it's a fluid state.
Mary