And what a cutie she was !
I might steal your idea if the leghorns keep struggling in the bath.
While I haven't used DE internally, I used it a lot on my chickens and in my coop before I came upon BYC. It's the main product used here against parasites like in the Netherlands I guess. I still use it once in a while in the coop, but a lot less. I don't feel comfortable using it internally in the feed though.
I have been a user of the mite traps since I have a coop, but they are mostly inefficient in my coop, probably because I have too many points of access to the roosts, and I think the mites live on the floor in the hay. I almost never see mites in the traps, even when I’m seeing some on the feed barrel.
I’ve said before that my coop due to it's nature will never be parasite free so I concentrate on trying to keep the mites off the roosts. I use in turn a pyrethrin spray, a surfactant spray, juniper tar, and now my partner burns the roosts with the gas torch. I also use a lot of wood ashes now, in the litter and on the ramp. But honestly the main thing that impacts the mites population is the heat. It gets out of control when the nights stay around 20/ 68 degrees.
Regarding the deworming, I probably didn't make myself clear that I see the six months as a minimum safe duration, meaning that I don't plan to deworm the whole flock more than that. I don't agree with routine deworming of the flock when you know you have worms in your environment at a fixed date. I also think deworming should only be done if you see signs of overload or health issues. We did a global deworming in mid may even though there was no sign of worms because the breeder who sold us the chickens told us they needed deworming. Then I saw a few tapeworm segments just two weeks after. So I'm not repeating this mistake. What I fear is that the day I have a sick chicken that really needs a deworming the worms will have become resistant because I have been feeding them Flubendazole two or three times a year for years. I have the same problem with the cats. My question is what the best strategy would be in a worm loaded environment so as not to develop resistance and without endangering the chicken's health. Most people say you need to deworm the whole flock, but if I do that everytime I have a worm problem I don't think Flubendazole will keep on working.(I have also found a few french writings on that since it's a real question for the egg industry now more layer hens are outside. There is a real financial issue, so my guess is there will be some research to produce another egg safe dewormer, but maybe not in years.)
I have the same problem with my cats, by the way. I deworm them and a month after they are pooping worms again

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