Chicken not growing or gaining weight

[dcross@1966]

We have a 6 month old rhode island red hen. She eats good but she is not growing or gaining any weight. She doesn't even have food in her crop stored up. Does anyone have any ideas what this could be?

 

[CrestedGirl]

Have you wormed her at all?

 

[dcross@1966]

No, what is the best wormer to use. Does it sound like it is worms? Would the other chickens that she is around get worms also? She is the only one like that.