My barn has decided to add Diatomacious Earth to all horses’ feed to control worms. I can’t see that this would be harmful, but is there any evidence that it is helpful in any way? Not just opinion or anecdotal…
It’s the shells of sea creatures, right? I don’t think it would be good to eat.
However I do put it on ant beds to kill ants, since it is less dangerous than the poisonous pellets sold to kill ants. My horses always check out whatever I put on anything.
I would not feed it to horses. Why not just buy wormer to kill worms? Usually on sale somewhere although the 50 pound bag of crushed sea shells is much cheaper. The dia-earth prevents the outer shell on ants from developing, according to what I was told. It makes my ants disappear which is what I want. I hope it does not kill earth worms.
It is effective to kill insects by cutting up the keratin exoskeleton. That doesn’t sound good for the stomach lining of horses, but from what I’ve seen and read, it is harmless to horses in the amount typically fed. It is also harmless to the worns, since it is diluted in such a quantity of feed
IMO best control for worns in addition to actual worming is excellent sanitary conditions in paddock and fields. That would reduce the reinfection level.
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Diatomaceous earth (DE) is not made of crushed sea shells, but diatoms. Diatoms are single cell algae which have a cell wall made of silica. I have used DE in my garden to control insects and slugs.
I agree with Scribbler. If DE can slice and kill internal parasites, why does it not damage the GI tract? Can someone explain this to me? I control parasites with good pasture management and judicious use of chemical dewormers.
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I would worry more about inhalation and breathing/lung problems. Although most food-grade DE is amorphous, it frequently has some of the crystalline form in it also. Amorphous DE has been shown to cause some lung problems and irritation, but the crystalline kind is much worse. Never, ever use the crystalline kind made for pool filters!
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I would hope they are feeding it in a wet mash, and using food grade.
I think that at the amounts fed, it is harmless to both horse and worms, and unless the BM can show consistent fecal tests that prove none of the horses being fed this are carrying worms, to work on the assumption it is ineffective at worm control. So OP should not stop her regular worming protocol.
Here is a link from a DVM
http://equusmagazine.com/management/diatomaceous-earth-dewormer-15880
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DE becomes completely ineffective as soon as it gets wet. The horse’s digestive tract is wet, therefore, DE is completely ineffective.
And it is not harmless - it lulls horse owners into believing that it is doing something, when in fact, it is doing nothing at all, and simply allowing worm loads to grow.
A dear friend who was the biggest DE advocate you could ever meet nearly lost her Rocky Mountain mare to a MASSIVE worm load after years of feeding DE.
If your barn does move forward with it, I strongly encourage you to still do fecal egg counts to stay on top of a growing worm situation.
Pease educate yourself as much as possible. Here’s a good article:
http://www.listentoyourhorse.com/clinical-studies-on-diatomaceous-earth-as-a-natural-de-wormer/
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This.
It works with cockroaches in pantries as long as it’s dry.
Feeding it to horses as a parasite control substance is a waste of time.
G.
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Myself, I think using DE for worm control is a lot of Bovine Manure, I have no intention of relying on it. I do FECs and worm accordingly and on the advice of the vet. I am concerned about the herd worm load, tho, so will share the articles and posts with my BM. She sometimes doesn’t think things through completely…
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We feed it from March until killing frosts in the fall to help reduce the fly population and it seems to have helped with that. It is one of the ingredients in the feed thru fly control products. We do fecals and worm as indicated so I am pretty sure this stuff doesn’t do in worms! It is great for removing ticks though-put some on the tick and the little bugger will back right out so you can destroy it!
According to all the equine vets on VIN (Veterinary Information Network, where all the cool vets hang out:winkgrin:), there is no proven efficacy of DE. And the problems with inhalation are real.
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I’ve never fed it, but have used it in my yard for flea and tick control and used to put it in the manure pile to control insects. Works great for that!
Texas A&M did a preliminary study on DE and equine internal parasites. They didn’t find any evidence of effectiveness.
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Scarlet Gilia is correct. DE is made of crushed diatoms mined from the sea. They are millions of years old.
I use it in my chicken bedding, nest boxes, and dust baths. Since I started using it about 5 or 6 years ago, I have NEVER had a case of scaly leg on my poultry. It does work wonders that way. I do put a small amount of DE powder in the girls’ layers mash, but also worm them with Flubinvet twice a year. If the DE gets wet, it does NOT dissolve. Its main purpose is as a desiccant. It dries out liquids, be they in bugs, mites, lice, flies, slugs and snails, weevils, ants too name a few. There’s even a liquid DE spray for wasps.
The most important point about DE is that it must be pure food grade, not industrial grade or swimming pool DE.
I have plastic puffer bottles of DE that I use to apply the powder to my Shires’ leg feather with a modicum of success. If I don’t coat the entire area of skin under the feather, there are patches where the mites cause itchiness.
As far as feeding it to my horses and donkeys, I would think the amount I would have to use would be somewhat concerning. The jury is out on that front.
As above–dry, it works as an insecticide. Fed to horses or ruminants as an anthelmintic, it is of no use.
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Wouldn’t that be because it slices through the exoskeleton and allows the insides to dry out on exposure to the air?
No “slicing” involved.
“Diatomaceous earth is widely used as an insecticide and appears to be effective in that role. The porous DE can absorb more than its own weight in water and exerts its effect through absorption of liquid from the waxy layer of the exoskeleton or outer covering of insects, causing them to dehydrate and die. Water moves according to Fick’s Law of diffusion, migrating from areas of high water concentration to areas of lower concentration. These conditions exist around pests such as fleas and lice in the external environment of animals but probably not in the intestinal tract where worms exist.”
The stuff is primarily silica. Sames as those little packets of dessicant you sometimes find in a shoebox or other packaging.
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IME, it does a whole lot of nothing. Nothing noticeable anyway.
A vet once recommended I feed food grade DE for a multitude of things, including joint support and hoof improvement. Cited articles to back these claims up (they are out there, if you google it I’m sure you’ll find something). Anyway, I fed it for a while based on this vet rec and nothing changed, no noticeable improvement in anything so I stopped feeding it. I think people do think it’s doing something, and people also like feeling like they are doing natural things. I am for natural things if they work, but that is not my experience with DE.
ETA: saw again in the OP that OP doesn’t want anecdotal evidence, and that is exactly what I did. Sorry!
Actually, it works by abrading the carapace AND acting as an absorbent https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4025297/
“DE, a powdery substance, has been made from the fossilized remains of unicellular algae known as a diatom. This powder contains 1% crystalline silica. According to WHO guideline, DE needs to be less than 2% of crystalline silica in order to be considered safe. DE mode of action for insects control is mechanical. DE sharp edge makes mechanical abrasions on the thin wax covering of insects. This coating cover prevents water loss from the cuticle surface. DE also absorbs the oil easily, so it is effective at absorbing protective waxy covering.”
Here are SEM image of diatoms.
http://commtechlab.msu.edu/sites/dlc…o/zwp0530.html
http://eukaryoticmicrobe.blogspot.co…tom-essay.html
DE usually contains radiolaria and sponge spicules also.
http://www.psmicrographs.co.uk/radiolarian-sem/science-image/rad027
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The idea that the microscopic sharp silica crystals scratch the exoskeleton of the bugs causing loss of bodily fluids is an outdated, old school notion.
“The current authoritative texts confirm that the ‘mode of action’ of DE causes the insects to die of dehydration. Serious investigators have long understood DE’s mechanical action on insects as follows: ‘All fossil diatoms are porous, and it is this porosity or specific surface (square meters per gram) that confers them their insecticidal value’ (Ebeling 1971).”
“The diatom’s lattice-like architecture creates pores. These pores create a large surface area which gives the dust its absorptive quality, capable of absorbing 1 1/2 times its weight in water. With this special capacity to absorb both oil and water through the vast number of pores, DE soaks up the protective waxy outer covering on the insect, which then allows body fluids to be absorbed or depleted, and organ functions to stop, with possible interference of the breathing mechanism.”
DE won’t work on bugs that have a constant source of food and water which replenishes the loss of fluids. However, ultimately they will perish if they are in constant contact with DE.
My own experience has been dramatic with my hens. I have had varying results using DE with my Shires. About 3 years ago, I blitzed my pole barn with 150 kilos of DE, removing all bedding, cobwebs, feeders, hay, every and any thing that could harbour mites. The horses were out 24/7 at that time. Before bringing them in in the autumn, I blitzed the Shires’ feathers with shampoo. I was mite free for several months. I believe the slow occurrence of itchy legs on a couple of my horses had to be due to the hay (we use cardboard bedding) and the mites that reside in the bales. I realise this is anecdotal evidence, but I do know of several people whose successful use of DE with their poultry is unequivocal.
