My ladies really are enjoying their yogurt, i use plain and sprinkle it with the feed. Now how often is appropriate, they seem to be tolerating it very well, but i don't want to overdo it obviously. They are turning 5mths old. Thank you.
It's pretty much the same with any treat; feed in moderation (once to three times a week depending on how many chickens you have; the more chickens, the more often you can feed the treat since it is spread throughout the whole flock). Yogurt is very good for chickens, but should not be fed so much that it seems to replace the basic feed.