Ivermectin poisoning

I was looking at a bird site trying to figure out how much Ivermectin a chicken can tolerate over a short period of time and I found this on a bird site:

Signs Of Ivermectin Poisoning
The clinical signs of Ivermectin poisoning are:

excessive dilatation of the pupil of the eye
lethargy
stupor
coma
tremors
loss of coordination of the muscles, especially of the extremities (ataxia)
vomiting (emesis)
drooling
death

Less visible symptoms:

depression
tachycardia (fast pulse)
blood pressure fluctuation

Although it was posted on a bird site, the "drooling" sign has me wondering if it does pertain to chickens or if it was generalized from signs in dogs. The bird in question was a budgie and it was being treated by a vet. Everything else just stated that overdose causes death but I could not find anything related to the onset of symptoms or if there was a chance of survival once the bird was poisoned.

When I use the pour on for cattle, I use the dosage measure cup on the small $20 bottle (I pour the liquid into the smaller bottle from the bigger $50 bottle) set at the lowest possible setting. I have not measured in drops or used a cc syringe so I am not sure exactly how much I use but it should be a strong dose. I know that the mites have to bite the chicken to be effected and that new hatches of eggs have to hatch and feed on the chicken in order to die and break the cycle. I was under the impression that it only needed to be used every six months so I treated the beginning of October and again the beginning of April. I have not done a secomd dose because I thought there would still be a strong enough dose to kill anything that hatched after the first dose. Do I need to treat all the birds I treated a week ago or will the dose I gave them be enough to kill any mites that find their way to my birds?

When I treated in October I also used DE in the coop but I did not use it in April because I have asthma and I don't want to breathe the dust or cause respiratory problems in my birds. I still have some DE left over so I can use it in combination if that would eliminate the need for any further ivermectin treatment or I can treat with ivermectin again but I don't want to poison my birds. When I used DE on my Silkies they were sneezing and I was afraid they were sick until I read that the dust causes irritation that causes sneezing. I know some people dust their Silkies with DE on a regular basis but I decided to let them use dirt like my other chickens.

Has anyone experienced or witnessed ivermectin poisoning in chickens? If a bird has been poisoned and is showing signs, is there a chance it will survive? If the pour on kills mites immediately, I am assuming an overdose would also show up right away, especially if the bird was also stressed and/or overheated. If other dusting agents are used on a chicken showing signs of poisoning, will it cause further problems or is it safe to use topicals since the ivermectin is absorbed into the skin?

Good luck with getting relevant info on this subject, it's worth knowing for sure.

I don't personally use chemicals but would assume it's safer for poultry than dogs in general due to the sheer prevalence of people using it regularly on their birds and not reporting mass flock deaths, but as it's likely cumulative over generations, in future I would expect them to become hyper-sensitive to it like some dogs are. Also, people don't tend to cull and replace dogs every two years, so that's something to take into account.

I don't know of anything much you could do to reverse such poisoning because it's not a natural poison so would probably take something unnatural to treat it, i.e. methylchloroisothiazolinone cumulative reactions being treated with chemotherapy and anti-rejection drugs in extreme cases. Bizarre stuff! That was in humans though, don't know what you would use for animals there.

Drooling is one of the standard severe toxicity responses in anything that salivates, so yes, birds would do it too.

Best wishes.

I measured the amount of liquid pour on I am using and it is about a teaspoon but not quite. I don't know how many cc or drops there are in a teaspoon but since I pour it onto the back of the neck between the shoulders, I think some gets on the feathers so not all of it makes it to the skin. I thought one mite treatment is good for 6 months but I am going to do it every 4 months from now on.

If mites are still visible on a chicken after this treatment method, how much more can a chicken take safely and how soon? I would rather a chicken deal with mites than to risk poisoning it by mistake and having it die.

Duck Drover said:

I measured the amount of liquid pour on I am using and it is about a teaspoon but not quite. I don't know how many cc or drops there are in a teaspoon but since I pour it onto the back of the neck between the shoulders, I think some gets on the feathers so not all of it makes it to the skin. I thought one mite treatment is good for 6 months but I am going to do it every 4 months from now on.

If mites are still visible on a chicken after this treatment method, how much more can a chicken take safely and how soon? I would rather a chicken deal with mites than to risk poisoning it by mistake and having it die.

Click to expand...

• 5ml in a teaspoon
• 5mg ivermectin per 1ml in pour on
• 10mg ivermectin per 1ml in injectable

The amount of pour on recommended is .5mg/kg, I think
The amount of injectable recommended is .2mg/kg, but I have seen vet books that say to use twice that.

One teaspoon (25mg) on one bird is way too much.

-Kathy

So, that would confirm that the dose I am using is already a mega dose and any more than that would very likely cause a severe, potentially lethal, reaction. How soon should a follow-up treatment be given after birds have been given this strong of a dose? My understanding is that doses need to be months apart because the ivermectin stays in the system to kill newly hatched mites. What dosing schedule is ideal for getting rid of mites completely?

Also, would a bird that has been poisoned have any chance of survival following.Ivermectin poisoning? How long would it take for the bird to recover if it were to survive without any treatment other than supportive care? If another mite treatment is used after a bird has already been poisoned, will the bird be able to handle a different treatment while trying to recover from the initial poisoning?

From: http://www.sciencelab.com/msds.php?msdsId=9924423
Toxicity to Animals:
Acute oral toxicity (LD50): 29.5 mg/kg [Mouse].

http://en.wikipedia.org/wiki/Median_lethal_dose
In toxicology, the median lethal dose, LD50, LC50 or LCt50 of a toxin, radiation, or pathogen is the dose required to kill half the members of a tested population after a specified test duration.

I'm tired, so I'll do some more research tomorrow and try to answer to questions.

-Kathy

Source: http://www.drugs.com/vet/ivermectin-pour-on.html
"Dosage

The dose rate is 1 mL for each 22 lb of body weight. The formulation should be applied along the topline in a narrow strip extending from the withers to the tailhead"

So 5ml is enough for 110 1 pound birds, 55 2 pound birds etc...

I'll go out on a limb any say that if they're still alive and look normal they'll be fine.

-Kathy

My birds have not had any problem with the heavy dose of ivermectin but clearly it is too much. The bird that is showing signs of poisoning belongs to someone else who medicated a bird that had already been medicated and I was wondering if there is any chance of survival once a bird is showing the symptoms listed above. I don't know if the damage can be reversed once it has been done.

I did not think mites could survive the dose I have been giving my birds but if there were mite eggs that hatched after the initial dose I think it is possible that mites could be observed prior to their taking a lethal bite from the chickens and that might give the appearance that they are infested. In all honesty, I am not in the habit of molesting my chickens so I allow them to preen themselves without taking it upon myself to groom them. The only time I have seen mites is on a bird that had scabbed over injuries (from being bullied by some young roosters) because I was checking the wounds and the dried blood seems to attract mites to the site of a wound.

I have put my faith in ivermectin to take care of any creepy crawlies that my chickens pick up while free ranging and I have also been trusting it to keep mites from infesting my coops because eventually they will feed on a treated bird and die. My flock came from a NPIP flock with a known mite problem but I was confident that the ivermectin would be effective in treating and protecting my flock. It seems I am giving an overly sufficient dose to kill mites while fortunately not killing the birds with such a high dose. I have even spilled the liquid on myself when pouring it from one bottle to another so I should be mite free as well, LOL!

I have read that depluming mites are harder to get rid of but I have had both lenses replaced due to cataracts and with the monocular vision I have would make it impossible to see anything so small with the range of vision I have with artificial lenses (one eye is more near sighted and the other is more far sighted but both my near and far vision are compromised). The thought of mites makes my skin crawl so I don't want my chickens to be crawling with them. If there were depluming mites that are resistent to ivermectin, it seems my chickens would show symptoms and they are all nice and fluffy.

The internet makes it so much easier to access information and yet there is also so much false and misleading information that it takes a great deal of research to learn anything useful that can be verified by multiple sources.

Since ivermectin has been overused as a miteacide in poultry for years and worms have built resistance to ivomec products, it wouldnt surprise me that mites are showing and/or have built resistance to ivomec products as well.