It's up to you. I've read some recent posts saying NOT to give them yogurt. Some do anyway though. I've done it before with a few of my hens and didn't notice any problems. My hen doesn't have an appetite though, if she was exhibiting normal behavior, I might just crush up some acidophilus tabs into her water... but right now, yogurt is one of the few things she will eat so I'm going to give it to her.