My chickens like yogurt, it could also be sprinkled on something like watermelon, which it would stick to. Some people have used peanut butter, although I've never given that to my birds. Scrambled eggs is popular for mixing meds or supplements. Oatmeal would work. What ever your chickens like, that is wet or the powder can be mixed into, in other words. Just a small amount, so the chicken will eat it all.