Ivermectin on chickens
In my opinion, using Ivermectin as a treatment for mites and lice (possibly some internal parasites also) in chickens is the best, easiest to administer, but unfortunately one of the most controversial.
Ivermectin is a derivative of Avermectin, a naturally occurring substance made from a living organism found only in Japan. Avermectin was discovered in the 1970’s and is considered one of the safest and most beneficial drugs ever developed (almost on par with aspirin and penicillin). It is used extensively for the treatment of parasites (internal and external) for animals and humans with great success and limited side effects. Without Ivermectin millions of people around the world would be suffering insidious parasitic bodily infestations causing horrible disfigurations and poor quality of life even death.
In animals, for the past 30 plus years, ivermectin has been used to treat livestock such as sheep and cattle protecting them from many awful parasites and increasing farming productivity hugely around the world.
There are many different brands and derivatives of Ivermectin. Some products are absorbed by ingestion through the animal’s water supply and others are placed on the skin through drenching or spraying animals.
Regardless of the delivery, Ivermectin works by entering the bloodstream and by direct contact to kill both internal and external parasites. Most backyard chicken keepers who use Ivermectin on their birds use it externally via drops on the back of the hen’s neck rather than via the water supply.
However, there are some with larger flocks who prefer to deliver the drug via the hen’s water because it’s easier. Although, it’s important to note dose rates and types of Ivermectin differ depending on how it is administered either by absorption through skin or ingestion.
The problem or sticking point in regards to using ivermectin on poultry is mainly administrative due to an oversight to not test it on chickens etc when the drug was first developed. The testing concentrated on larger animals and domestic pets with poultry inadvertently overlooked (this is my understanding from talking to people within the poultry industry). To date, this seems like the most plausible explanation as to why ivermectin was not initially tested on poultry although I can’t find a scientific reference for this theory.
Suffice to say, this lack of testing means ivermectin can’t be formally approved for use on fowl because a tested withholding period (if any) has not been established for egg or meat consumption reasons. Therefore, it can’t or probably shouldn’t legally be sold as a treatment for mites and lice on backyard chickens (in Australia that is). I should stress I have no legal advice or qualification to confirm this statement I’m mainly going off hearsay.
Ironically, avermectin/ivermectin can be sold to treat non-food birds such as parrots, and budgies, etc and is widely used in pet bird industries. This is where the line probably became crossed from pet bird to chicken when people realised how effective the product was on poultry also.
The confusion over the use of Ivermectin, its amazing effectiveness, and the temptation to retail it as a product to use for backyard chicken keepers on their flocks is evident by the fact that it is sold here in Australia and commercially marketed only by a few retailers but its continuation remains dubious.
As far as I know, Ivermectin as a treatment for mites, lice, and intestinal worms specifically for chickens was withdrawn from sale in Australia around 2013. At the time, there was no explanation from retailers (I know of) as to why the product was discontinued. However, it seems at least one retailer here in Australia has resumed selling Ivermectin targeted at chicken keepers again in 2015.
The retailer I’m talking about is City Chicks until they stopped selling the product (briefly), I purchased my Ivermectin online from City Chicks (one of two well-known online chicken retailers I knew of who sold the product here in Australia) and it was/is retailed in 100mil bottles. The product was initially marketed as an all-in-one internal and external parasite controller, meaning when used on poultry it effectively killed worms, mites, lice, and ticks.
However, Ivermectin sold by City Chicks is now only marketed for external parasite control and they have since changed their product statement to read, “Ivermectin is not considered reliable for internal parasite treatment which is why we are recommending its use in conjunction with Avitrol Plus worming tablets or syrup”.
For this particular product, the recommended dose for a standard sized chicken is 1 mil placed on the back of the hen’s neck on the skin every 3 months or when parasites were apparent (I used half the dose for quail or bantams). My testing and use of Ivermectin on my poultry (chickens, ducks, and quail) proved very effective against both external parasites like mites/lice and internal parasites such as roundworms.
The recommended withholding period for the Ivermectin product sold by City Chicks is 5 days for chickens or other poultry. In other words, it is recommended eggs or meat from birds treated with Ivermectin should not be consumed by humans until 5 days after treatment – after 5 days, the levels of the drug in the bird's system is considered negligible and the consumption of eggs or meat from the poultry can resume.
Of course, the obvious questions are: who came up with the withholding period? Why was ivermectin “for chickens” withdrawn from sale or why do so few retailers sell it? And, what was exactly in the ivermectin product? I don’t know the definitive answer to any of these questions but I suspect a vet came up with the withholding period taking into consideration the known legal withholding periods for other animals.
And, the reason why few retailers here in Australia actually sell Ivermectin for chickens and those who did stop selling ivermectin (albeit briefly) was due to Australian law prohibiting a product to be sold for any other purpose other than what it was originally intended. Since ivermectin is not officially approved for the use on poultry then technically it’s against the law to sell it for this purpose – or, is it? That’s my understanding from talking to others within the poultry industry anyway…
Finally, what was the exact Ivermectin based product I purchased? Well, since the bottle is relabelled it only contains directions for use and the word Ivermectin, which wasn’t overly helpful since there are many derivatives of this chemical.
I can make an educated guess and say the Ivermectin product I was buying online is most likely Moxidectin, which is readily sold under several brand names. City Chicks probably purchased the Moxidectin in bulk and then rebottled it into 100mil bottles for resale. There’s more about using and purchasing Moxidectin at the end of this segment… Edit: Since the publishing of this article it seems City Chicks has again withdrawn its ivermectin-based product as I can't seem to find it for sale on their Website anymore – lucky I stocked up…
So why doesn’t someone just test it and get ivermectin approved then?! Well, unfortunately, it isn’t as easy as that – I wish it were… Firstly, testing a drug and running trials to convince a regulatory authority that it’s safe to use costs money – possibly millions of dollars.
Secondly, there has to be a push/ground swell and NEED for a product to be developed and currently there are other ways to control mites and lice in poultry that also work.
These other products (some we’ll discuss later in this article) are not as effective or as easy to administer as ivermectin; however, they still work nevertheless so the appetite to re-trial ivermectin just to prove it’s safe to use on backyard chickens is virtually nil.
Still, the lack of formal approval has not stopped ivermectin being used on chickens and other poultry. Industry professionals like veterinarians often prescribe ivermectin for chickens to eradicate mites and lice.
A celebrity vet here in Australia called Dr Harry once presented a TV segment on the popular show Better Homes and Gardens where he recommended using ivermectin to treat scaly leg mites on a backyard chicken. So, obviously, vets can prescribe ivermectin as a treatment for external parasites it’s just that the public can’t easily buy it for this purpose. Weird hey…
I know of people who have a good relationship with their vet and buy ivermectin in bulk from them to use on their chickens. Another of the online poultry supplies shops I visit still has small print on their website encouraging customers to contact them privately if they wish to by ivermectin to use specifically on chickens but they don’t list the product formally in their online store.
Last year (2014), I visited our annual show in Brisbane (EKKA) which has a large poultry pavilion and a guy at one of the stands inside was selling small bottles of their very own “miracle cure” for mites and lice on chickens. I asked the gentleman running the stand what was in their concoction and when pressed he admitted (quietly) it was ivermectin based.
Clearly, the use of ivermectin on poultry is currently in a confusing mess even though it is widely used amongst the poultry industry worldwide. It’s a shame people who want to use this product (like me) have to go underground to purchase it or search high and low for a retailer who stocks it.
Having said all that, whew… Another very important consideration for people who do decide to source Ivermectin independently for use on their poultry (because it is readily available) is the dose and particularly the type of Ivermectin because not all Ivermectin based products are the same.
Some Ivermectin based products used for other animals may actually contain other substances that could harm chickens so please don’t just buy any Ivermectin based product off the shelf and guess it should work as this would be stupid. If in doubt seek vet advice.
From my research, Ivermectin based products called Moxidectin (with 5g/L), or commonly sheep dip, or brand named Cydectin Sheep Drench, are "supposedly" considered safe to use on poultry. Edit: However, since writing this article there have been several readers commenting to the contrary for example:
Ivomectin and moxidectin are NOT the same, do not confuse them! Moxidectin is a 2nd generation macrolitic compound with dosages for sheep cattle horse. It is dangerous to overdose and would be easily done in chickens. There is no conspiracy re ivomectin, it is easily purchased online or in ag/stockfeed stores in many generic or brand names (ivomec). You only need a tiny drop (o.1ml for adult standard chicken 0.05ml for bantam) on the back of the neck. To be safe allow a 21 day witholding period for meat, not sure for eggs. Moxidectin is 4 times the price as it is a recent development and there is less resistance BUT it hasn't been researcged enough in birds off label or not so don't risk it, research scientific papers or ask vets about off label use of ivomec if uncertain on dosage for the bottle you buy. Legally your poultry supplier can't sell in smaller batches off label that is why they come and go from sale as they are probably getting audited. That would be like me selling you single panadol tablets, labelled 'miracle head ache cures' There are laws to protect the consumer not just to ruin our fun!
If anything the above quote from our comments section (and there are several others) demonstrates perfectly what I mean by ivermectin being such a confusing and controversial product, particularly when associated with poultry!
Ivermectin (Ivomec) can be purchased here on eBay (Australia) for very reasonable prices but as I keep stating your purchase and use of this product or derivatives is to be used with caution and at your own risk! In the USA this product is sold on eBay and also Amazon with people claiming to use it on their chickens – contact the seller for more information about dosages and use.
The dose for chickens when using ivermectin is apparently 0.5mil per kg or about 1mil for a standard sized hen usually administered by placing the dose on the back of the neck via an eyedropper or syringe (without a needle). Again, I must stress this information has been gathered from unauthorised sources and you should check with your vet before using anything on your hens contrary to the label!
If you’d like to read more about the origins and benefits of Ivermectin have a read of this article published on The National Center for Biotechnology Information (USA)– it’s quite in-depth but very well written!
I really do wish I could be more definitive with regards to the type of ivermectin treatment, exact product recommendations, and dosage but unfortunately, I can't… This is a great pity and a good (some would say typical) demonstration of how poor management by regulatory authorities regarding a product can cause mass confusion.
