Hi, everyone. I'm a long time reader/lurker on this forum, but I've never joined before because I don't have chickens. I'd like to someday, but it won't be in the near future, so I content myself with learning as much as I can from more experienced people. But I found something that pertains to this discussion that I thought might interest others, so I finally joined.
Anyway, the July issue of the journal Poultry Science published a study on feeding diatomaceous earth to chickens. The study was done by the Avian Research Centre at the University of British Columbia. The bottom line is "The results of this study indicate the DE has the potential to be an effective treatment to help control parasites and improve production of organically raised, free-range layer hens."
For those interested in reading the abstract, it says:
The effectiveness of diatomaceous earth (DE) as a treatment against parasites and to increase feed efficiency and egg production of organically raised free-range layer hens was evaluated in 2 breeds of commercial egg layers [Bovan Brown (BB) and Lowmann Brown (LB)] that differ in their resistance to internal parasitic infections. Half the hens of each breed were fed diets supplemented with DE (2%). Their internal parasite loads were assessed by biweekly fecal egg counts (FEC) and by postmortem examination of the gastrointestinal tract. Supplementing DE in diets of LB hens, the more parasite-resistant breed, did not significantly affect their FEC and adult parasite load. However, BB hens treated with dietary DE had significantly lower Capillaria FEC, slightly lower Eimeria FEC, fewer birds infected with Heterakis, and significantly lower Heterakis worm burden than control BB hens. Both BB and LB hens fed the diet containing DE were significantly heavier, laid more eggs, and consumed more feed than hens fed the control diet, but feed efficiency did not differ between the 2 dietary treatments. Additionally, BB hens consuming the DE diet laid larger eggs containing more albumen and yolk than hens consuming the control diet. In a subsequent experiment, the effectiveness of DE to treat a Northern fowl mite (Ornithonyssus sylviarum) infestation was tested. Relative to controls, both breeds of hens that were dusted with DE had reduced number of mites. The results of this study indicate the DE has the potential to be an effective treatment to help control parasites and improve production of organically raised, free-range layer hens.