To DE Or Not To DE

The use of Diatomaceous Earth (DE) for the treatment of parasites in chickens is one of those polarizing threads in Facebook Chicken groups. It seems you either love it or hate it, use or shun it. I’m a bit of a fence-sitter on this one. I don’t dispute that it works for some applications, but also have some reservations that it is the go-to for many conditions, and perhaps used too liberally without awareness of its risks and limitations.

So what exactly is DE? It’s the fossilized remains of diatoms – microscopic algae – that are mostly comprised of silicon dioxide with razor-sharp edges. DE is divided into two types: amorphous, which is labeled as ‘food grade’ and crystalline, which is too sharp for use on animals.

It’s usually used for treating external parasites and insects (mites, lice, fleas, ticks, ants, spiders, aphids, termites, flies and fly larvae) that affect poultry by sprinkling it in bedding, nest boxes and dust bathing areas. Some folks apply DE directly onto affected birds.

As a mechanical, rather than chemical, pesticide it works by damaging the waxy cuticle or coating on insects and parasites, killing them by drying them out within a few days after coming into direct contact with DE.

Some people also use DE for internal parasites, but this is not nearly as effective as its use for external parasites. I found one study about the use of DE to treat internal parasites: there were varying rates of reduction of worms in one group of birds and none in another. I was unable to find information as to how it works, other than it cuts internal parasites in the same way as external ones. If that is the case, I have concerns about potential damage to a chicken’s digestive system.  I, personally, would not feed DE to my birds because I think there are several more effective and safer ways to treat worms.

The Pros

• It’s readily available, reasonably priced and easy to use.
• DE is effective for treating external parasites.
• There is no egg withdrawal period.

The Downside

• The number one consideration should be the health and safety of our birds. Although DE is a naturally occurring organic substance there are health risks: it creates microscopic cuts in skin, the digestive tract and respiratory system. It is known to cause airsacculitis and respiratory issues. If you are applying it directly on your birds use a limited amount and infrequently.
• When using DE you should wear a mask to avoid inhaling it, as it can damage your lungs.
• It is indiscriminate and will kill parasites as well as any beneficial insects it comes into contact with. If you use it outside your coop be aware of that fact and use it judiciously to protect bees and butterflies and other insects that we want to provide a healthy environment for.
• If you use the deep litter method to compost coop bedding, then don’t use DE or it will affect the colony of bacteria and microorganisms and kill fly larvae and worms that are essential for it to work properly.
• It is not effective for infestations. A high parasite load may kill your birds before the DE works.
• Although DE comes from prehistoric algae it is harvested through strip mining, which is not environmentally friendly.

Alternatives to DE

• Understand that parasites affecting chickens are ubiquitous – they are in the environment and in our birds most of the time. It is only when their numbers are high and are birds are carrying a heavy load or infestation that it usually becomes a problem.
• Provide year-round covered access to dust bathing areas. That can be as simple as allowing your birds to make a hollow in the dirt or containing sand or wood ashes in a tire, kiddie pool or tote. Dust bathing kills external parasites like mites and lice.
• Sulfur is an organic pesticide that is effective in treating mites.
• Add crushed garlic to their waterers. It boosts their immune systems as well as helps to prevent various internal worms.
• Permethrin and Elector PSP can be used for lice and mites; Ivermectin for mites, lice and various worms (except tapeworms) and Piperazine for roundworms.