Hi all, I posted about this subject a few weeks back and got lots of lookers, but no comments so thought I'd post an update about my experience. I spent a lot of time watching the chickens and mulling this one over. I read any and everything I could find but never found a word on the subject, so I'll tell you what we did. We ended up bringing in all the ponies for the incoming tropical storm we had last week. The hens were all snug up in the hen house too so decided it was the perfect time to control what happened with the pass through on the pony poo. All ponies were dewormed with an ivermectin product. All manure for the next 24 hours or so was scooped and spread far from the house where the girls wouldn't have access to it. Reading various sources, they say it probably takes a week or so for the deworming products to clear the ponies' systems. Honestly, I think any avoidance for the hens wasn't really necessary because I've watched them scratch. They don't scratch in the manure to eat bugs IN it as much as UNDER it. So, that's what happened. No ill effects for anyone and I have the best flock (5) of manure spreaders anyone could ask for. I can't begin to say how much I like having chickens with the horses and ponies. It seems to make the ponies much calmer about all the things that go on in life and they all seem to enjoy each other's company, especially my aged stallion who has his own hen keeping him company most of the day. The added benefit of not having to drag paddocks as often goes without saying. I used to hitch up and drag weekly but they keep things so spread out, it is no longer necessary. Their spreading the manure probably has the added benefit of killing any parasites exposed to our hot sun too. Win win here. Cheers! Deb W 2 americaunas, 3 golden dark laced wyandottes, 3 cats, one crazy border collie cross and 6 wonderful Welsh ponies.