Poor chicken, but stuff happens. If your going to let him eat it, I would pluck it and gut it prior to giving it to him,, The heart/liver should be ok, but the rest I just wouldn't feed him

And I'd cut it up, not sure you want to give a whole chicken to a 16 week old all at once??
Raw feeders would know better than I, but that's just what I would do.
Yeppie, your wife's parents sound like patient dog owners (not

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If your chickens are friendly, maybe you can introduce them in a controlled environment? I have 9 chickens, my aussies would love to pounce/pin/probably kill them,,my gsd is fine with them, however I mine are locked in a run and never with the dog unsupervised.
Sorry you lost your chicken