It looks like your feeding the dog on chicken legs,i would not advise because i did that and the dog became ill a so a trip to the vets the vet then confirmed piece of bone stuck in the bowl. cost me over £700.00 never again the vet said its regular thing this in working type dogs due to there diet.im only giving you a tip mate.
Definately raw chicken you was giving him?
yes mate been feeding it for near on twenty year amongst other things never had a problem yet,why do you ask