Don't waste your money on the Wazine it will not kill all the worms, especially the ones that you saw segments on.. Buy the paste that is listed on the other thread or the Valbezan, I read your post there also. I have posted there also.. all your chickens will be good for the smaller ones...
Yes, it is.. And usually when you see signs they have a good load of them.. You can get the horse wormer paste at most livestock / feed stores (TSC, COOP etc.) if you have one close by. They may not have the Valbezan, mine don't so you will probably have to order it online.
Read through this thread we were just discussing worming.. Worms will lead to diareaha and death in birds, they can not absorb nutrition. After worming you should see their poo start to solidify, you have to follow up with the second dose at the recommended time...