Why is it harmful for bones to be cooked before feeding to dogs?

My MIL makes soup using marrow and/or knuckle bones. She saved the bones for our dog and I currently have them in the freezer because I read that cooked bones are dangerous. These are big, smooth bones, maybe even too big for my dog to carry.

What are the dangers?


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bague de fiancaille

Cooked bones splinter and can perforate a dog's digestive system.