There are a bunch of stables next to the local race track, and they put bagged horse manure on the footpath for anyone to take. However there is no way to know whether the manure is from a horse that has been recently wormed or not.

I collected a couple of bags 12 days ago and put them into a couple of small open bottomed compost tubs I have. I turn it most days and have added water when I found ants getting involved.

3 days ago I put a small amount into an ice cream container and added 10 adult EF worms. After 2 days I counted and there were still 10 healthy looking worms.

Any thoughts on whether I need to wait longer before assuming the manure is safe and can be used in my worm farm?

I am no expert on this subject but severial people have said that by the time the dewormer leaves the horse in is nutralized .But IMHO testing like you have done is the only sure way to be sure.

I would wait at least 14 days to see if they die.
BUT, if you have seen ants, then saturate the manure with water until they are gone before putting it in your bins. Ants are hard to get rid of and such a nuisance. I have found drowning them works better than just about anything to make them move on.
Liz

BT, do you mean leave the manure 2 weeks to compost, or leave the worms in it for 2 weeks?

It better not be the latter!

I built a wheelie bin Flow Through on the weekend (very proud of it I might add), moved the contents of 3 COW trays in and let it sit a couple of days.

This morning I added about a litre of horse dung to one corner, but I did a recount of my test bucket at 5 days and all 10 were still looking happy.

12 hours later I just had a look, and I am amazed at how fast and furiously they are attacking the manure!

My thoughts are that horses don't digest stuff well, so most likely a worming agent will have to act fairly fast to be able to do any damage before getting passed out again.

The manure has been composting for 17 days and 10/10 worms survived for 5 days, so I like the chances of it being safe.

Fingers crossed!

would it be that the actual composting of the manure, gettingup to the right temp to kill any seed growth, may also cook off any horse chemicals?

when you turn it do you wet it down? i have a friend with some horses, thinking of asking for some

how about some pics of the flow through you built

I don't think I have enough for it to get that hot. I was given a tumbleweed composter with a broken base, so I undid the bolts around the middle to make 2 halves and used them as compost bins. As you might imagine, they aren't big. I added a fair bit of water when I got the poo, which probably helped wash the urine out and into the soil below as the nasty smell had gone by the next day.

After that I didn't add much water until I noticed the ants.

I added 850 grams of poo to a different corner this morning, it's now 10.5 hours later and they are all over it. From about 6 hours, I could see them nibbling at the edges and probably underneath as well.