We use ivermectin paste to worm our Great Pyrenees dogs. Works great! Also you absolutely can worm chickens with it and it would kill everything I imagine.. even gape worms which I've never encountered but heard can be a bugger to get rid of. I think the dosage is what.. a pea sized amount or something like that? Is that right? Worms can most definitely become tolerant to wormers so it is good practice to rotate wormers every so often.
We really like the wormazole pills. We have some roosters that will take them all by themselves. All you have to do is drop it on the ground and they swallow it right down. lol. Others you have to push it down their throat to make sure they swallow it or else they can spit them back out. I'll be out there talking to them like now boys take your medicine.. lol. Yep I talk to my chickens.