Yes, chickens are omnivorous, meaning that they can consume and their digestive systems can process a wide array of food sources. Naturally, they eat bugs and worms sometimes even their own flock mates, and many are fed bone and feather meal today. Widely used feed formulations include bone meal and other animal derived substances (including from other birds).
The American Association of Feed Control Officials (AAFCO) has also published guidelines which state animal protein can be safely incorporated into feed for other animals. There's no evidence that including animal proteins in a chicken’s diet poses a risk for the proliferation of Prion disease.