I make goat milk soap and use DE in my soaps. It acts like a very mild abrasive. You really can't feel it in the lather, but it helps abrade that fine top layer of dead skin cells (somewhat). Otherwise, I don't have a lot of use for the stuff. I did try feeding it to the horses as a dewormer but one filly choked on her feed so bad and all the goats were miserable at their dinner, I abandoned the project. A recommended method of plant use (to get rid of insect pests) is to mix it with some flour and puff it over the plants. Besides killing whatever the plant had going on, I'd think it'd clog the leaves, making it difficult for the plant to do it's own work as well as kill beneficials too.
TAMU did some studies on DE vs commercial dewormers in feedlot Boer goats and found that DE doesn't eliminate parasites, but keeps them to a minimal number that the animal can tolerate. Maybe so, but my own trials showed that it's not easy nor likeable to the livestock. I have been told that the commercial flour manufacturers are allowed to put a certain amount of DE in our flour and other grain products to keep coddling moths at a minimum, so we're eating the stuff whether we like it or not. I don't know it for a fact, but it wouldn't surprise me.
