Our three cats do not bother our hens. When we had chicks this spring, these were left alone too, maybe because of their protective adoptive Silkie mamas. It's funny, when the hens are free ranging n the late afternoon and come up by the house where the cats are waiting for their dinner (spoiled, yes), if the cats are on the grass or patio where the chickens come, the hens will run them off, stare them down, thoroughly intimidate our cats, both "house" and barn.