I thought it's what every chicken lived for! I first offered earthworms at week 7, but nothing. They would pick it up, drop it, shake their heads, glare at it, then walk away. Every single time. It's still the same today, at 19 weeks. They could care less about the worms! They like grubs, mealworms, waxworms, moths, and any other insect imaginable. But in my small 1/3 of an acre yard, there's 90% earthworms and 10% others. I feel they don't get all the protein that is offered to them, since they pass up any earthworm they see. My duck on the otherhand, can live entirely off the worms she digs up if I didn't feed her.