So, a few months back I had a chicken start to loose weight rapidly. I immediately thought it was worms. I bought some horse wormer, with ivermectin as the main ingredient (some one's suggestion on here I believe) and gave her a pea size amount and the rest of the flock too. It didn't seem to help at all. She eventually just withered into nothing and died. Recently after her death, I bought 8 lavendar orpington chicks which I have had major problems with because they weren't in the best shape when I got them. (Former owners had horrible living conditions. But I couldn't leave them there like that. Lesson learned though!) Anyways I have two of them who aren't gaining weight right now. Everyone else is fine besides these two and it's so much like the other chicken. I gave them wormer and nothing. I don't even see worms in their feces. (I have them separated and locked up) Someone please help! I dont know what is going on. Besides the weightloss, they eat fine, drink fine, and move around fine. And if it is worms, please help me understand how to dose them better or a different brand that may have worked for you.