Chicken is not suitable towards their nutritional requirements! They are insectivores through and through. Pre-killed insects seriously lack in nutrition, live insects should be gut-loaded (fed nutritious foods such as carrots, dark leafy greens, apple etc) and should be dusted with calcium and vitamin supplements every other feeding. You may offer certain fruits as treats such as sliced grape, apple, prune, raspberry etc but it's unlikely they will accept it.

It is most likely that they will not eat pre-killed anyway, they are a rather fussy species, preferring live any day! Mine will also give an insect a nudge to make sure it's alive.

If it's any consolation, there are scientific studies showing that insects do not feel pain, they lack the appropraite receptors to do so.

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