It will need to be mixed with a high carbon material and precomposted.

Pony would be Horse Manure, its about how the digestive system works. Equine Excrement is only around 25% processed the remainder being whatever you were feeding it. Cow manure is more processed but the worms will love it all the same. Cows are much more efficient about getting what they need from their feed but the manure is still worm heaven. You could also mix the two, seems I read somewhere a commercial recipe being a combination of the two along with other amendments.

Chazz - I wish that I was your neighbor so that I could borrow a few cups of your cow manure.